WO2004099880A1 - 有機光導電性材料、それを用いた電子写真感光体および画像形成装置 - Google Patents
有機光導電性材料、それを用いた電子写真感光体および画像形成装置 Download PDFInfo
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- WO2004099880A1 WO2004099880A1 PCT/JP2004/006590 JP2004006590W WO2004099880A1 WO 2004099880 A1 WO2004099880 A1 WO 2004099880A1 JP 2004006590 W JP2004006590 W JP 2004006590W WO 2004099880 A1 WO2004099880 A1 WO 2004099880A1
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- C07D311/02—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only hetero atom, condensed with other rings ortho- or peri-condensed with carbocyclic rings or ring systems
- C07D311/04—Benzo[b]pyrans, not hydrogenated in the carbocyclic ring
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- C07C211/57—Compounds containing amino groups bound to a carbon skeleton having amino groups bound to carbon atoms of six-membered aromatic rings of the carbon skeleton having amino groups bound to carbon atoms of six-membered aromatic rings being part of condensed ring systems of the carbon skeleton
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- C07C211/57—Compounds containing amino groups bound to a carbon skeleton having amino groups bound to carbon atoms of six-membered aromatic rings of the carbon skeleton having amino groups bound to carbon atoms of six-membered aromatic rings being part of condensed ring systems of the carbon skeleton
- C07C211/61—Compounds containing amino groups bound to a carbon skeleton having amino groups bound to carbon atoms of six-membered aromatic rings of the carbon skeleton having amino groups bound to carbon atoms of six-membered aromatic rings being part of condensed ring systems of the carbon skeleton with at least one of the condensed ring systems formed by three or more rings
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- C07D207/30—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having two double bonds between ring members or between ring members and non-ring members
- C07D207/34—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having two double bonds between ring members or between ring members and non-ring members with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
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- C07D209/80—[b, c]- or [b, d]-condensed
- C07D209/82—Carbazoles; Hydrogenated carbazoles
- C07D209/86—Carbazoles; Hydrogenated carbazoles with only hydrogen atoms, hydrocarbon or substituted hydrocarbon radicals, directly attached to carbon atoms of the ring system
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- C07D209/80—[b, c]- or [b, d]-condensed
- C07D209/82—Carbazoles; Hydrogenated carbazoles
- C07D209/88—Carbazoles; Hydrogenated carbazoles with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to carbon atoms of the ring system
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- C07D233/54—Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, not condensed with other rings having two double bonds between ring members or between ring members and non-ring members
- C07D233/66—Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, not condensed with other rings having two double bonds between ring members or between ring members and non-ring members with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D233/88—Nitrogen atoms, e.g. allantoin
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- C07D263/00—Heterocyclic compounds containing 1,3-oxazole or hydrogenated 1,3-oxazole rings
- C07D263/52—Heterocyclic compounds containing 1,3-oxazole or hydrogenated 1,3-oxazole rings condensed with carbocyclic rings or ring systems
- C07D263/54—Benzoxazoles; Hydrogenated benzoxazoles
- C07D263/58—Benzoxazoles; Hydrogenated benzoxazoles with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached in position 2
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- C07D277/60—Heterocyclic compounds containing 1,3-thiazole or hydrogenated 1,3-thiazole rings condensed with carbocyclic rings or ring systems
- C07D277/62—Benzothiazoles
- C07D277/64—Benzothiazoles with only hydrocarbon or substituted hydrocarbon radicals attached in position 2
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- C07D307/02—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings
- C07D307/34—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members
- C07D307/38—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members with substituted hydrocarbon radicals attached to ring carbon atoms
- C07D307/52—Radicals substituted by nitrogen atoms not forming part of a nitro radical
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- C07D307/02—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings
- C07D307/34—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members
- C07D307/56—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D307/66—Nitrogen atoms
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- C07D307/77—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom ortho- or peri-condensed with carbocyclic rings or ring systems
- C07D307/78—Benzo [b] furans; Hydrogenated benzo [b] furans
- C07D307/82—Benzo [b] furans; Hydrogenated benzo [b] furans with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to carbon atoms of the hetero ring
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- C07D333/00—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom
- C07D333/02—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom not condensed with other rings
- C07D333/04—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom not condensed with other rings not substituted on the ring sulphur atom
- C07D333/06—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom not condensed with other rings not substituted on the ring sulphur atom with only hydrogen atoms, hydrocarbon or substituted hydrocarbon radicals, directly attached to the ring carbon atoms
- C07D333/14—Radicals substituted by singly bound hetero atoms other than halogen
- C07D333/20—Radicals substituted by singly bound hetero atoms other than halogen by nitrogen atoms
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- C07D333/02—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom not condensed with other rings
- C07D333/04—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom not condensed with other rings not substituted on the ring sulphur atom
- C07D333/26—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom not condensed with other rings not substituted on the ring sulphur atom with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D333/30—Hetero atoms other than halogen
- C07D333/36—Nitrogen atoms
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- C07D335/00—Heterocyclic compounds containing six-membered rings having one sulfur atom as the only ring hetero atom
- C07D335/04—Heterocyclic compounds containing six-membered rings having one sulfur atom as the only ring hetero atom condensed with carbocyclic rings or ring systems
- C07D335/10—Dibenzothiopyrans; Hydrogenated dibenzothiopyrans
- C07D335/12—Thioxanthenes
- C07D335/20—Thioxanthenes with hydrocarbon radicals, substituted by amino radicals, directly attached in position 9
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
- G03G5/02—Charge-receiving layers
- G03G5/04—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
- G03G5/06—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being organic
- G03G5/0601—Acyclic or carbocyclic compounds
- G03G5/0612—Acyclic or carbocyclic compounds containing nitrogen
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
- G03G5/02—Charge-receiving layers
- G03G5/04—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
- G03G5/06—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being organic
- G03G5/0601—Acyclic or carbocyclic compounds
- G03G5/0612—Acyclic or carbocyclic compounds containing nitrogen
- G03G5/0614—Amines
- G03G5/06142—Amines arylamine
- G03G5/06147—Amines arylamine alkenylarylamine
- G03G5/061473—Amines arylamine alkenylarylamine plural alkenyl groups linked directly to the same aryl group
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
- G03G5/02—Charge-receiving layers
- G03G5/04—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
- G03G5/06—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being organic
- G03G5/0601—Acyclic or carbocyclic compounds
- G03G5/0612—Acyclic or carbocyclic compounds containing nitrogen
- G03G5/0614—Amines
- G03G5/06149—Amines enamine
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
- G03G5/02—Charge-receiving layers
- G03G5/04—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
- G03G5/06—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being organic
- G03G5/0601—Acyclic or carbocyclic compounds
- G03G5/0612—Acyclic or carbocyclic compounds containing nitrogen
- G03G5/0616—Hydrazines; Hydrazones
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
- G03G5/02—Charge-receiving layers
- G03G5/04—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
- G03G5/06—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being organic
- G03G5/0664—Dyes
- G03G5/0666—Dyes containing a methine or polymethine group
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C2603/00—Systems containing at least three condensed rings
- C07C2603/02—Ortho- or ortho- and peri-condensed systems
- C07C2603/04—Ortho- or ortho- and peri-condensed systems containing three rings
- C07C2603/22—Ortho- or ortho- and peri-condensed systems containing three rings containing only six-membered rings
- C07C2603/24—Anthracenes; Hydrogenated anthracenes
Definitions
- the present invention relates to an organic photoconductive material, an electrophotographic photoreceptor using the same, and an image forming apparatus.
- electrophotographic photoreceptors using organic photoconductive materials are used not only in the field of copiers but also in fields such as printing plates, slide films, and microfilms where photographic technology was conventionally used. I have. Furthermore, it is also applied to high-speed printers using a laser, light emitting diode (abbreviation: LED) or cathode ray tube (CRT) as a light source. Therefore, requirements for organic photoconductive materials and electrophotographic photoreceptors using the same will be high and broad.
- LED light emitting diode
- CRT cathode ray tube
- an inorganic photoreceptor having a photosensitive layer mainly composed of an inorganic photoconductive material such as selenium, zinc oxide or cadmium has been widely used.
- Inorganic photoreceptors have some basic properties as a photoreceptor, but have problems such as difficulty in forming a photosensitive layer, poor plasticity, and high manufacturing costs.
- inorganic photoconductive materials are generally highly toxic and have significant restrictions on manufacturing and handling.
- an organic photoreceptor using an organic photoconductive material has an immense photosensitive layer. Excellent flexibility, light weight and good transparency.
- this organic photoreceptor has the advantage that it can easily design a photoreceptor that shows good sensitivity over a wide wavelength range by an appropriate sensitization method. It has been developed as The early organic photoreceptors had shortcomings in sensitivity and durability, but these shortcomings were attributed to the development of functionally separated electrophotographic photoreceptors in which the charge generation function and the charge transport function were assigned to different substances. Significantly improved.
- the function-separated type photoreceptor has a wide material selection range for each of the charge generation material that has the charge generation function and the charge transport material that has the charge transport function.
- Examples of the charge generating substance used in such a function-separated type photoreceptor include phthalocyanine pigments, squarylium dyes, azo pigments, perylene pigments, polycyclic quinone pigments, cyanine dyes, squaric acid dyes, and pyrylium salt dyes.
- phthalocyanine pigments phthalocyanine pigments
- squarylium dyes azo pigments
- perylene pigments polycyclic quinone pigments
- cyanine dyes cyanine dyes
- squaric acid dyes pyrylium salt dyes
- charge transport materials include pyrazoline compounds (see JP-B-52-4188), hydrazone compounds (JP-A-54-150128, JP-B-55-42380, and JP-A-55-38080).
- pyrazoline compounds see JP-B-52-4188
- hydrazone compounds JP-A-54-150128, JP-B-55-42380, and JP-A-55-38080.
- triphenylamine compounds see JP-B-58-32372 and JP-A-2-190862
- stilbene compounds see JP-A-54-151955.
- Various compounds are known.
- pyrene derivatives, naphthalene derivatives and Yuichi-phenyl derivatives see Japanese Patent Application Laid-Open No. 7-48324) having a condensed polycyclic hydrocarbon system as a central nucleus have been developed.
- Charge transport materials include:
- the charge transport material is required to have a high charge transport ability.
- the charge transport layer formed by dispersing the charge transport material together with the binder resin becomes the surface layer of the photoreceptor, the charge transport material must have a high charge transport capability in order to secure sufficient photoresponsiveness. Desired.
- the surface layer of the photoconductor must be partially removed by a contact member such as a cleaning blade or a charging roller. Be forced to.
- a surface layer that is strong against those contact members that is, a surface layer with high printing durability that is hardly scraped off by those contact members. Therefore, if the content of the binder resin in the charge transport layer as the surface layer is increased in order to strengthen the surface layer and improve the durability, the light responsiveness is reduced. This is because the charge-transporting substance in the charge-transporting layer is diluted with an increase in the binder resin content because the charge-transporting substance has a low charge-transporting ability, and the charge-transporting layer further reduces the charge-transporting ability, resulting in a light response. It becomes worse.
- the charge transport material is required to have a high charge transport ability.
- JP-A Japanese Patent Application Laid-Open
- the photoreceptor is required to have a high sensitivity even when used in a low-temperature environment without a decrease in sensitivity and a small change in characteristics under various environments. No charge transport material that achieves its properties has been obtained. Disclosure of the invention
- the name according to the present invention is characterized by having the following configuration or means, and solves the above object.
- the present invention is an organic photoconductive material represented by the following general formula (1).
- n is an integer of 0 to 3
- Ar 1 and Ar 2 are each an aryl group which may have a substituent or a heterocyclic group which may have a substituent
- Ar 3 and Ar 5 are different from each other and are an arylene group which may have a substituent, or a divalent heterocyclic group which may have a substituent
- Ar 4 and Ar 5 are A hydrogen atom, an aryl group which may have a substituent, a heterocyclic group which may have a substituent, an aralkyl group which may have a substituent, and a substituent is any of alkyl groups, and ⁇ , never a r 4 and a r 5 is both a hydrogen atom, a r 4 and a r 5 is bonded to each other via an atom or atomic group, the ring structure R 1 is a hydrogen atom, a halogen atom, or an alkyl group which may have a substituent, and R 2 , R 3 and R 4 are
- the organic photoconductive material is an enamine compound represented by the general formula (1), it has high charge mobility.
- the organic photoconductive material can be used as a charge transporting substance. As a result, the charged potential is high, high sensitivity, sufficient photoresponse is exhibited, and the durability is excellent.
- the organic photoconductive material is used for a sensor material, an EL element, an electrostatic recording element, or the like, a device having excellent responsiveness can be provided. Further, the present invention provides the organic photoconductive material represented by the general formula (1),
- j and 1 are each an integer of 1 to 5
- m is an integer of 1 to 6
- a, b and d are an alkyl group which may have a substituent, An alkoxy group which may be substituted, a dialkylamino group which may be substituted, a aryl group which may be substituted, and any one of a halogen atom and a hydrogen atom;
- B and d may be the same or different when a plurality of them are represented in the formula.
- the organic photoconductive material represented by the general formula (1) is, in particular, an enamine compound represented by the aforementioned general formula (2) using an asymmetric secondary naphthylamine which is the cheapest and easily available.
- Introducing a phenyl group having a substituent as a structural unit of the enamine moiety has excellent compatibility with the binder resin, does not cause adverse effects such as partial crystallization during film formation, and has high charge mobility.
- An organic photoconductive material having the following can be easily obtained.
- an electrophotographic photoreceptor having a high charge potential, high sensitivity, and sufficient photoresponsiveness can be realized.
- Highly reliable electrophotographic photoreceptors with excellent durability, their characteristics do not deteriorate even when used in low-temperature environments or high-speed processes, and their characteristics do not deteriorate even when exposed to vigorous light. Can be realized.
- the organic photoconductive material is used for a sensor material, an EL element, an electrostatic recording element, or the like, a device having excellent responsiveness can be provided.
- an electrophotographic photosensitive member comprising: a conductive support made of a conductive material according to the present invention; and a photosensitive layer provided on the conductive support and containing a charge generating substance and a charge transporting substance.
- the charge transport material includes the organic photoconductive material.
- the photosensitive layer contains, as a charge transport material, an organic photoconductive material having high charge mobility represented by the general formula (1), for example, (2). It is possible to obtain an electrophotographic photoreceptor having a high degree of sensitivity, high sensitivity, sufficient photoresponse, excellent durability, and whose properties are not deteriorated even when used in a low-temperature environment or in a high-speed process. In addition, since high charge transporting ability can be realized without including polysilane in the photosensitive layer, a highly reliable electrophotographic photosensitive member without deterioration in characteristics due to light exposure can be obtained.
- the charge generation substance contains oxotitanium phthalocyanine.
- the photosensitive layer has a charge generating substance having a Bragg angle (20 ⁇ 0.2 °) in Cu—K characteristic X-ray diffraction (wavelength: 1.54 A) of at least 27 • 2. And oxotitanium phthalocyanine having a clear diffraction peak.
- Cu-K characteristics Oxo titanine fuocyanine, which has a distinct diffraction peak at X-ray diffraction (wavelength: 1.54A) with a Bragg angle (20 soil 0.2 °) of at least 27.2 °, has high charge generation efficiency and Charge injection efficiency.
- the photosensitive layer contains an organic photoconductive material having high charge mobility represented by the general formula (1), for example, (2) as a charge transporting substance. Therefore, the charge generated by the charge generating substance due to light absorption is efficiently injected into the charge transporting substance and transported smoothly, so that a high-sensitivity and high-resolution electrophotographic photosensitive member can be obtained. .
- the photosensitive layer has a laminated structure of a charge generation layer containing the charge generation substance and a charge transport layer containing the charge transport substance.
- the photosensitive layer has a laminated structure of a charge generating layer containing a charge generating substance and a charge transporting layer containing a charge transporting substance.
- the charge transport layer further contains a binder resin.
- the ratio AZB between the charge transport substance (A) and the binder resin (B) is 10/12 to: L by mass. 0Z30.
- the charge transport material (A) contained in the charge transport layer and the binder resin is the charge transport material (A) contained in the charge transport layer and the binder resin
- ratio A / B is 10/12 (10/12)-10/30 by mass ratio (10/30).
- the ratio A / B is set to 10 12 to 10/30, and the conventionally known charge transporting substance is used. Even when a binder resin is added at a higher ratio than when a substance is used, the light responsiveness can be maintained. Therefore, it is possible to improve the printing durability of the charge transport layer and to improve the durability of the electrophotographic photosensitive member without deteriorating the light responsiveness.
- the present invention is characterized in that an intermediate layer is provided between the conductive support and the photosensitive layer.
- an intermediate layer is provided between the conductive support and the photosensitive layer. This prevents the injection of charges from the conductive support into the photosensitive layer, thereby preventing a decrease in the chargeability of the photosensitive layer and reducing the surface charges other than those to be erased by exposure. To prevent the occurrence of defects such as fogging in the image.
- the film forming property of the photosensitive layer is improved. Further, peeling of the photosensitive layer from the conductive support can be suppressed, and the adhesiveness between the conductive support and the photosensitive layer can be improved.
- an image forming apparatus including the electrophotographic photosensitive member.
- FIG. 1 is a schematic cross-sectional view showing a simplified configuration of an electrophotographic photosensitive member that is an example of the present embodiment.
- FIG. 2 is a schematic cross-sectional view showing a simplified configuration of an electrophotographic photosensitive member as another example of the present embodiment.
- FIG. 3 is a schematic cross-sectional view showing a simplified configuration of an electrophotographic photosensitive member that is still another example of the present embodiment.
- FIG. 4 is a configuration diagram showing a simplified configuration of an image forming apparatus including the electrophotographic photosensitive member according to the present invention.
- FIG. 5 is a diagram showing a 1 H-NMR spectrum of Exemplified Compound No. 28 (1-1) of the present example.
- FIG. 6 is a diagram showing a 13 C-NMR spectrum of the exemplary compound No. 28 (1-1) of the present example by a normal measurement.
- FIG. 7 is an enlarged view of 110 ppm to 150 ppm of the spectrum diagram shown in FIG.
- FIG. 8 is a diagram of a 13 C-NMR spectrum of Exemplified Compound No. 28 (1-1) of this example measured by DEPT 135.
- FIG. 9 is an enlarged diagram showing 110 to 150 ppm of the spectrum diagram shown in FIG. BEST MODE FOR CARRYING OUT THE INVENTION
- the organic photoconductive material of the present invention is an enamine compound represented by the following general formula (1).
- Ar 1 and Ar 2 each represent a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group.
- a r 1 and A r 2 is phenyl, tolyl, methoxyphenyl, Ariru groups such as naphthyl and Bifue two Lil, and furyl, thienyl, thiazolyl, heterocycles such Ben Zofuriru and N- methyl indolyl Groups can be mentioned.
- Ar 3 and Ar 6 are different from each other, and may be an arylene group which may have a substituent, or a divalent heterocyclic group which may have a substituent. Is shown.
- Ar 3 and Ar 6 include p-phenylene, m-phenylene, methyl-
- Aryl groups such as P-phenylene, methoxy-P-phenylene, m-naphthylene, ⁇ -naphthylene, pyrene, biphenylene, biphenylene, phenoxyphenylene and phenylthiophenylene, 1,4-furyl, 1,4-Chenyl, 1,4-thiazolyl, 2,5-benzofuryl, 2,5-benzothiophenyl, 2,5- ⁇ -methylindolyl, 1,5-benzothiazolyl 2,5-, Heterocyclic groups such as benzoxazolyl and 3,6-diethylcarbazolyl can be mentioned.
- Ar 4 and Ar 5 each represent a hydrogen atom, an aryl group which may have a substituent, a heterocyclic group which may have a substituent, or a substituent. It is selected from an aralkyl group which may have and an alkyl group which may have a substituent. However, both Ar 4 and Ar 5 do not become hydrogen atoms.
- Ar 4 and Ar 5 include phenyl and tolyl except for a hydrogen atom. , Methoxyphenyl, naphthyl, pyrenyl, biphenyl, biphenyl, phenyloxy, p- (phenylthio) phenyl and p-styrylphenyl, and other aryl groups, furyl, phenyl, thienyl, thiazolyl, benzofuryl, benzothiophenyl, N— Heterocyclic groups such as methylindolyl, benzothiazolyl, benzoxazolyl and N-ethylcarbazolyl, aralkyl groups such as benzyl, p-methoxybenzyl and 1-naphthylmethyl, and methyl, ethyl, trifluoromethyl, fluoromethyl, Examples include alkyl groups such as isopropyl, t-butyl, cyclohexyl,
- Ar 4 and Ar 5 may be bonded to each other via an atom or an atomic group to form a ring structure.
- Specific examples of the atom bonding Ar 4 and Ar 5 include an oxygen atom and a sulfur atom.
- R 1 represents a hydrogen atom, a halogen atom or an alkyl group which may have a substituent.
- R 1, other than hydrogen atom include methyl, Echiru, n _ propyl, alkyl groups such as isopropyl and triflates Ruo Russia methyl, and a halogen atom such as fluorine atom and chlorine atom.
- R 2 , R 3 and R 4 each have a hydrogen atom, an alkyl group which may have a substituent, an aryl group which may have a substituent, and a substituent. And an aralkyl group which may have a substituent.
- R 2 , R 3 and R 4 include, except for a hydrogen atom, alkyl groups such as methyl, ethyl, n-propyl, isopropyl, trifluoromethyl and 2-phenylmethyl, phenyl, tolyl, methoxyphenyl and the like.
- aryl groups such as naphthyl, heterocyclic groups such as furyl, phenyl and thiazolyl, and aralkyl groups such as benzyl and P-methoxybenzyl.
- R 2 , R 3 and R 4 when two or more R 2 , R 3 and R 4 are represented, they may be the same or different from each other as long as they are the groups listed above.
- n represents an integer of 0 to 3
- Ar 3 represents a heterocyclic group which may have a substituent.
- the organic photoconductive material of the present invention is an enamine compound represented by the general formula (1), it has high charge mobility.
- the charge potential is high, the sensitivity is high, sufficient photoresponsiveness is exhibited, the durability is excellent, and the temperature is low.
- a highly reliable electrophotographic photoreceptor whose properties do not deteriorate even when used in an environment or in a high-speed process, and whose properties do not deteriorate even when exposed to light. Further, when the organic photoconductive material is used for a sensor material, an EL element, an electrostatic recording element, or the like, a device having excellent responsiveness is provided.
- preferred compounds include an enamine compound represented by the following general formula (2).
- j, m, and 1 indicate the number of substituents, and a, b, and d indicate the types of the substituents.
- m is in the range of 1 to 6
- j and 1 are in the range of 1 to 5.
- a, b, and d are an alkyl group which may have a substituent, an alkoxy group which may have a substituent, a dialkylamino group which may have a substituent, and a substituent
- a diaryl group or a halogen atom and in a, b, and d, the above-mentioned groups are divalent or more divalent groups such as diylene, and these are bonded to each other to form a ring structure. May be formed.
- two or more groups are represented in the general formula (2), they may be the same or different from each other as long as they are the groups listed above.
- a, b, and d include, except for a hydrogen atom, alkyl groups such as methyl, ethyl, n-propyl, isopropyl, trifluoromethyl, fluoromethyl, and 1-methoxethyl, methoxy, ethoxy, n-propoxy, and iso-alkyl. Mention may be made of alkoxy groups such as propoxy, dialkylamino groups such as dimethylamino, getylamino and diisopropylamino, aryl groups such as phenyl, tolyl, methoxyphenyl and naphthyl, and halogen atoms such as fluorine and chlorine.
- alkoxy groups such as propoxy
- dialkylamino groups such as dimethylamino
- aryl groups such as phenyl, tolyl, methoxyphenyl and naphthyl
- the enamine compound represented by the general formula (2) has particularly high charge mobility. Also, it can be easily manufactured. Therefore, when the organic photoconductive material represented by the general formula (1) is a more specific enamine compound represented by the general formula (2), the organic photoconductive material having a particularly high charge mobility Is easily obtained.
- a r 1 and A r 2 is a phenylene group
- a r 3 is an ⁇ -naphthyl group
- a r 6 is a ⁇ -phenylene group, a methyl-P-phenylene group, a methoxy-P-phenylene group, a 1,4-biphenylene group, or a 1, 4- A phenyl group wherein at least one of Ar 4 and Ar 5 is phenyl; , P-tolyl, p-methoxyphenyl, naphthyl, chenyl or thiazolyl, wherein R 1 , R 2 , R 3 and R 4 are all hydrogen and n is 1 Can be mentioned.
- organic photoconductive material of the present invention represented by the general formula (1) include, for example, exemplary compounds having the groups shown in Tables 1 to 16 below. This does not limit the organic photoconductive material of the present invention.
- each group shown in Table 1 corresponds to each group of the general formula (1).
- Exemplified Compound No. 28 shown in Table 6 below is an enamine compound represented by the following structural formula (1-1).
- the enamine compound represented by the general formula (1) which is the organic photoconductive material of the present invention, can be produced, for example, as follows.
- an aldehyde compound or ketone compound represented by the following general formula (3) and a secondary amine compound represented by the following general formula (4) are subjected to a dehydration condensation reaction to obtain a compound represented by the following general formula (5).
- the indicated enamine intermediate is prepared. ° (3)
- This dehydration condensation reaction is performed, for example, as follows.
- a catalyst for example, an acid catalyst such as P-toluenesulfonic acid, camphorsulfonic acid or pyridinium-p-toluenesulfonic acid is added to the prepared solution, and reacted under heating.
- the amount of the catalyst to be added is 1/10 (1/10) to 1/1000 (1/1000) molar equivalent to the aldehyde compound or ketone compound represented by the general formula (3).
- the enamine intermediate represented by the general formula (5) can be produced in high yield.
- the enamine intermediate represented by the general formula (5) is subjected to bisformylation by a Vilsmeier reaction or bisacylation by a Friedel-Loukraft reaction to obtain an enamine-bis compound represented by the following general formula (6).
- R 5 represents R 4 when n is 0, and represents R 2 when n is 1, 2 or 3.
- Ar 1 , Ar 2 , Ar 3 , Ar 6 , and R 1 have the same meaning as defined in the general formula (1).
- the Vilsmeier reaction is performed, for example, as follows.
- a solvent such as N, N-dimethylformamide (abbreviation: DMF) or 1,2-dichloromethane
- Add phosphorus oxychloride and N, N-diphenylformamide to prepare Vilsmeier reagent.
- To the prepared Vilsmeier reagent 2.0 equivalents to 2.3 equivalents, 1.0 equivalent of the enamine intermediate represented by the above general formula (5) was added. 60 to: L 2 to 8 under heating at 10 ° C. Stir for hours.
- hydrolysis is carried out with an aqueous solution of sodium hydroxide such as a 1 to 8N aqueous solution of sodium hydroxide or an aqueous solution of hydroxide power.
- an enamine-bis-propionyl intermediate in which R 2 is a hydrogen atom can be produced in high yield.
- the Friedel-Crafts reaction is performed, for example, as follows.
- a reagent prepared from aluminum chloride and an acid chloride in a solvent such as 1,2-dichloromethane ethane 2.0 to 2.3 equivalents, and an enamine intermediate represented by the general formula (5) Add 1 • 0 equivalents and stir at 40-80 ° C for 2-8 hours. At this time, if necessary, heating is performed. Thereafter, hydrolysis is carried out with an alkaline aqueous solution such as a 1-8N aqueous sodium hydroxide solution or a potassium hydroxide solution.
- R 6 represents an alkyl group which may have a substituent or a realyl group which may have a substituent.
- Ar 4 and Ar 5 are the same as defined in the general formula (1). This is synonymous with
- R 6 represents an alkyl group which may have a substituent or an aryl group which may have a substituent.
- N represents an integer of 1 to 3.
- Ar 4 , Ar 5 , R 2 , R 3 and R 4 have the same meanings as defined in formula (1).
- the Wittighe Horner reaction is performed, for example, as follows.
- a solvent such as toluene, xylene, dimethyl ether, tetrahydrofuran (abbreviation: THF)
- ethylene glycol dimethyl ether N, N-dimethylformamide or dimethyl sulfoxide
- the enamine represented by the above general formula (6) is dissolved in a solvent.
- Metal alkoxide base 2 Metal alkoxide base 2.
- the electrophotographic photoreceptor according to the present invention transports the organic photoconductive material of the present invention represented by the above-described general formula (1), for example, (2) by charge transport. It is used as a substance, and there are various embodiments. The details will be described below with reference to the drawings.
- FIG. 1 is a schematic cross-sectional view showing a simplified configuration of an electrophotographic photosensitive member 1 which is an example of the electrophotographic photosensitive member according to the present invention.
- the electrophotographic photoreceptor 1 is composed of a sheet-like conductive support 11 made of a conductive material, a charge generation layer 15 containing a charge generation substance 12, a charge transport substance 13, and a charge transport substance.
- the charge-generating substance 12 and the charge-transporting substance 13 are emphasized for the sake of illustration. However, in actuality, each layer is constituted or the components such as binder resin are uniformly dispersed. They are dispersed.
- the organic photoconductive material of the present invention As the charge transport substance 13, the organic photoconductive material of the present invention, the above-mentioned general formula (1), for example, an enamine compound having a high charge mobility represented by (2) is used. Contained. Therefore, an electrophotographic photoreceptor having a high charge potential, high sensitivity, sufficient photoresponsiveness, excellent durability, and which does not deteriorate in a low-temperature environment or in a high-speed process can be obtained. be able to. Also, since high charge transporting ability can be realized without containing polysilane in the photosensitive layer 14, a highly reliable electrophotographic photoreceptor whose characteristics are not deteriorated by light exposure can be obtained.
- the above-mentioned general formula (1) for example, an enamine compound having a high charge mobility represented by (2) is used. Contained. Therefore, an electrophotographic photoreceptor having a high charge potential, high sensitivity, sufficient photoresponsiveness, excellent durability, and which does not deteriorate in a low-temperature environment or in a
- the photosensitive layer 14 has a laminated structure of the charge generation layer 15 containing the charge generation substance 12 and the charge transport layer 16 containing the charge transport substance 13. In this way, by assigning the charge generation function and the charge transport function to different layers, it is possible to select the optimal material for each of the charge generation function and the charge transport function. Therefore, it is possible to obtain an electrophotographic photoreceptor having higher sensitivity and higher durability with increased stability during repeated use.
- Examples of the conductive material constituting the conductive support 11 include metal materials such as aluminum, aluminum alloy, copper, zinc, stainless steel, and titanium. Also, without being limited to these metal materials, polymer materials such as polyethylene terephthalate, nylon and polystyrene, those obtained by laminating metal foil on a surface such as hard paper or glass, those obtained by depositing metal materials, Alternatively, a layer of a conductive polymer such as a conductive polymer, tin oxide, indium oxide, or the like, which is deposited or coated, can be used.
- the shape of the conductive support 11 is a sheet shape in the electrophotographic photoreceptor 1, but is not limited thereto, and may be a cylindrical shape, a columnar shape, an endless belt shape, or the like.
- the surface of the conductive support 11 may be subjected to an anodizing film treatment, a surface treatment with a chemical or hot water, a coloring treatment, or a surface roughening within a range that does not affect the image quality. And the like.
- an electrophotographic process using a laser as an exposure light source the wavelength of the laser light is uniform, so that the incident laser light interferes with the light reflected within the electrophotographic photosensitive member, and interference fringes due to this interference appear on the image. And may cause image defects.
- the charge generation layer 15 is a charge generation material that generates charges by absorbing light.
- Substances effective as the charge generating substance 12 include azo pigments such as monoazo pigments, bisazo pigments and trisazo pigments, indigo pigments such as indigo and thioindigo, peryleneimide and perylene anhydride.
- Perylene pigments polycyclic quinone pigments such as anthraquinone and pyrenequinone, phthalocyanine pigments such as metal phthalocyanine and metal-free phthalocyanine, squarillium pigments, pyrylium salts and thiopyrylium salts And trifluoromethane dyes, and inorganic materials such as selenium and amorphous silicon.
- azo pigments such as monoazo pigments, bisazo pigments and trisazo pigments
- indigo pigments such as indigo and thioindigo
- peryleneimide and perylene anhydride peryleneimide and perylene anhydride.
- Perylene pigments polycyclic qui
- oxotitanium phthalocyanine is a charge generating substance with high charge generation efficiency and charge injection efficiency, it generates a large amount of charge by absorbing light and accumulates the generated charge inside. Injection into the charge transporting material 13 efficiently. Further, as described above, as the charge transporting substance 13, an organic photoconductive material having high charge mobility represented by the general formula (1), for example, (2) is used. Therefore, the charge generated in the charge generating substance 12 due to light absorption is efficiently injected into the charge transporting substance 13 and transported smoothly, so that a high-sensitivity and high-resolution electrophotographic photosensitive member can be obtained. Can be.
- the charge-generating substances 12 are triphenylmethane-based dyes represented by methyl violet, crystal violet, night blue, and Victoria pull 1, etc., erythrine multiplin, rhodamine B, octamine 3R, acridine orange and Acridine dyes such as flavocins, thiazine dyes such as methylene butyl and methylene architecture, oxazine dyes such as force pliables and meldables, cyanine dyes, styryl dyes, pyrylium salt dyes or the like It may be used in combination with a sensitizing dye such as thiopyridyl salt dye.
- a sensitizing dye such as thiopyridyl salt dye.
- the charge generation layer 15 may be formed by a method of vacuum-depositing the charge generation substance 12 on the conductive support 11 or by coating the charge generation layer 12 obtained by dispersing the charge generation substance 12 in a solvent. There is a method of applying the liquid on the conductive support 11. Among these, the charge generation substance 12 is dispersed by a conventionally known method in a binder resin solution obtained by mixing a binder resin as a binder in a solvent, and the obtained coating solution is subjected to electroconductivity. The method of coating on the support 11 is preferred. Hereinafter, this method will be described.
- Binder resins include, for example, polyester resin, polystyrene resin, polyurethane Tan resin, phenolic resin, alkyd resin, melamine resin, epoxy resin, silicone resin, acrylic resin, methyl acryl resin, polycarbonate resin, polycarbonate resin, phenoxy resin, polybierptylal resin, and polyvinyl formal resin And one kind selected from the group consisting of copolymer resins containing two or more of the repeating units constituting these resins, or a mixture of two or more kinds.
- the copolymer resin examples include insulating resins such as vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate-maleic anhydride copolymer resin, and acrylonitrile-styrene copolymer resin. be able to.
- the binder resin is not limited to these, and a commonly used resin can be used as the binder resin.
- Esters such as ethyl acetate and butyl acetate; ethers such as tetrahydrofuran (THF) and dioxane; alkyl ethers of ethylene glycol such as 1,2-dimethoxyethane; aromatics such as benzene, toluene and xylene. Hydrocarbons or aprotic polar solvents such as N, N-dimethylformamide and N, N-dimethylacetamide are used. Further, a mixed solvent obtained by mixing two or more of these solvents can also be used.
- THF tetrahydrofuran
- alkyl ethers of ethylene glycol such as 1,2-dimethoxyethane
- aromatics such as benzene, toluene and xylene.
- Hydrocarbons or aprotic polar solvents such as N, N-dimethylformamide and N, N-dimethylacetamide are used. Further, a mixed solvent obtained by mixing two or more
- the compounding ratio of the charge generating material 12 to the binder resin is preferably such that the ratio of the charge generating material 12 is in the range of 10% by mass to 99% by mass. If the proportion of the charge generating substance 12 is less than 10% by mass, the sensitivity is reduced. When the ratio of the charge generating substance 12 exceeds 9.9% by mass, not only the film strength of the charge generating layer 15 decreases, but also the dispersibility of the charge generating substance 12 decreases and coarse particles increase. Since the surface charges other than those to be erased by exposure are reduced, image defects, particularly fogging of an image called a black spot, in which toner adheres to a white background and minute black spots are formed, increase. Therefore, it was set to 10% by mass to 99% by mass.
- the charge generating substance 12 Before dispersing the charge generating substance 12 in the binder resin solution, the charge generating substance 12 may be previously ground by a pulverizer.
- a pulverizer used for the pulverization treatment include a pole mill, a sand mill, an attritor, a vibration mill, and an ultrasonic disperser.
- Examples of the dispersing machine used for dispersing the charge generating substance 12 in the binder resin solution include Paintshiri, Pole Mill and Sand Mill. Appropriate dispersion conditions are selected so that impurities are not mixed due to abrasion of the container used and members constituting the disperser.
- the coating solution for the charge generating layer obtained by dispersing the charge generating substance 12 in a binder resin solution can be applied by a spray method, a vacuum coating method, a mouth coating method, a blade method, a ring method, and dipping. Coating methods and the like can be mentioned. From these coating methods, the optimum method can be selected in consideration of the physical properties and productivity of the coating.
- a layer is formed on the conductive support 11 by immersing the conductive support 11 in a coating tank filled with a coating solution and then pulling the conductive support 11 at a constant speed or a gradually changing speed. This method is relatively simple, is excellent in terms of productivity and cost, and is widely used in the production of electrophotographic photoreceptors.
- the apparatus used for the dip coating method may be provided with a coating liquid dispersing apparatus typified by an ultrasonic generator in order to stabilize the dispersibility of the coating liquid.
- the thickness of the charge generation layer 15 is preferably from 0.05 m to 5 m, more preferably from 0.1 x m to 1 m. If the J3 thickness of the charge generation layer 15 is less than 0.05 m, the efficiency of light absorption is reduced and the sensitivity is reduced. If the thickness of the charge generation layer 15 exceeds 5 m, the charge transfer inside the charge generation layer becomes a rate-limiting step in the process of erasing the charge on the photoreceptor surface, and the sensitivity is reduced. Therefore, it was set to 0.05 m or more and 5 / z m or less.
- the charge transport layer 16 has an ability to receive and transport the charge generated by the charge generation substance 12 from the organic photoconductive material of the present invention represented by the general formula (1), for example, represented by (2).
- the charge transport material 13 is obtained by incorporating it into a binder resin 17.
- As the organic photoconductive material represented by the general formula (1), for example, (2) one kind selected from the group consisting of the exemplified compounds shown in Tables 1 to 16 described above alone or two kinds is selected. The above are mixed and used.
- the organic photoconductive material represented by the general formula (1), for example, (2) may be used as a mixture with another charge transport material.
- charge-transporting substances include phorbazole derivatives, oxazolyl derivatives, oxadiazole derivatives, thiazole derivatives, thiadiazol derivatives, triazole derivatives, imidazole derivatives, imidazolone derivatives, imidazolidine derivatives, bisimidazolidine derivatives, and styryl compounds.
- Hydrazone compounds polycyclic aromatic compounds, indole derivatives, pyrazoline derivatives, oxazolone derivatives, benzimidazole derivatives, quinazoline derivatives, benzofuran derivatives, acridine derivatives, phenazine derivatives, aminostilbene derivatives, triarylamine derivatives, triarylmethanes Derivatives, phenylenediamine derivatives, stilbene derivatives, and benzidine derivatives.
- polymers having a group derived from these compounds in the main chain or side chain such as poly-N-vinylcarbazole, poly-1-vinylpyrene, and poly-9-vinylanthracene are also included.
- the entire amount of the charge transporting substance 13 may be the organic photoconductive material of the present invention represented by the general formula (1), for example, (2). preferable.
- a resin having excellent compatibility with the charge transport material 13 is selected.
- Specific examples include polymethyl methacrylate resins, polystyrene resins, biel polymer resins such as polychlorinated biel resins, and copolymer resins thereof, as well as polycarbonate resins, polyester resins, polyester carbonate resins, polysulfone resins, and phenoxy resins.
- Resin, epoxy tree Resins such as resin, silicone resin, polyarylate resin, polyamide resin, polyether resin, polyurethane resin, polyacrylamide resin, and phenol resin.
- a thermosetting resin obtained by partially cross-linking these resins may be used.
- polystyrene resin, polypropionate resin, polyarylate resin and polyphenylene oxide have a volume resistance value of 10 13 ⁇ or more, have excellent electrical insulation properties, and have good film properties and potential. It is particularly preferable to use these as the binder resin 17 because of their excellent properties.
- the electrophotographic photoreceptor 1 has a / 12-; L 0/30.
- the charge transporting substance 13 includes the organic photoconductive material of the present invention having a high charge mobility represented by the general formula (1), for example, (2), the ratio ⁇ is set to 10 ⁇ 12 to 10 ⁇ 30.
- the photoresponsiveness can be maintained. Therefore, the printing durability of the charge transport layer 16 can be improved and the durability of the electrophotographic photosensitive member can be improved without lowering the photoresponsiveness.
- the ratio ⁇ ⁇ is less than 10/30 and the ratio of the binder resin 17 is high, when the charge transport layer 16 is formed by the dip coating method, the viscosity of the coating liquid increases, so that the coating speed decreases and the production speed decreases. The property becomes significantly worse. If the amount of the solvent in the coating solution is increased in order to suppress the increase in the viscosity of the coating solution, a brushing phenomenon occurs, and the formed charge transport layer 16 becomes clouded.
- the ratio ⁇ / ⁇ exceeds 10 ⁇ 12 and the ratio of the binder resin 17 is low, the printing durability is lower than when the ratio of the binder resin 17 is high, and the abrasion amount of the photosensitive layer is increased.
- an additive such as a plasticizer or a leveling agent may be added to the charge transport layer 16 in order to improve film formability, flexibility and surface smoothness.
- the plasticizer include dibasic acid esters, fatty acid esters, phosphoric acid esters, phthalic acid esters, chlorinated paraffins, and epoxy-type plasticizers.
- the leveling agent include a silicone-based leveling agent.
- fine particles of an inorganic compound or an organic compound may be added to the charge transport layer 16 in order to enhance mechanical strength and improve electrical characteristics.
- various additives such as an antioxidant and a sensitizer may be added to the charge transport layer 16 as needed.
- an antioxidant and a sensitizer may be added to the charge transport layer 16 as needed.
- a hindered phenol derivative or a hindered amine derivative is preferably used.
- the hindered phenol derivative is preferably used in a range of 0.1% by mass to 50% by mass with respect to 13 of the charge transporting substance.
- the hindered amine derivative is preferably used in the range of 0.1% by mass to 50% by mass with respect to 13 of the charge transport material.
- the hindered phenol derivative and the hindered amine derivative may be used as a mixture. In this case, the total amount of the hindered phenol derivative and the hinderedamine derivative is preferably in the range of 0.1% by mass to 50% by mass with respect to the charge transporting substance 13.
- the amount of the hindered phenol derivative used, the amount of the hindered amine derivative used, or the total amount of the hindered phenol derivative and the hindered amine derivative is less than 0.1% by mass, the coating solution stability is improved and the durability of the photoreceptor is improved. It is not possible to obtain a sufficient effect to improve the performance. If the content exceeds 50% by mass, the photoconductor characteristics are adversely affected. Therefore, the content is set to 0.1% by mass or more and 50% by mass or less.
- the charge transport layer 16 is, for example, similar to the case of forming the charge generation layer 15 described above. Dissolve or disperse the charge transport material 13 and the binder resin 17 and, if necessary, the aforementioned additives in an appropriate solvent to prepare a coating solution for the charge transport layer, and spray the coating solution. It is formed by applying on the charge generation layer 15 by a method such as a bar coating method, a roll coating method, a blade method, a ring method or a dip coating method. Among these coating methods, the dip coating method is particularly used in forming the charge transport layer 16 because it is excellent in various points as described above.
- Solvents used in the coating solution include aromatic hydrocarbons such as benzene, toluene, xylene and monochlorobenzene, halogenated carbons such as dichloromethane and dichloroethane, ethers such as THF, dioxane and dimethoxymethyl ether. , And one kind selected from the group consisting of aprotic polar solvents such as N, N-dimethylformamide and the like are used alone or as a mixture of two or more kinds. If necessary, a solvent such as alcohols, acetonitrile or methyl ethyl ketone may be further added to the above-mentioned solvent.
- aromatic hydrocarbons such as benzene, toluene, xylene and monochlorobenzene
- halogenated carbons such as dichloromethane and dichloroethane
- ethers such as THF, dioxane and dimethoxymethyl ether.
- the thickness of the charge transport layer 16 is preferably 5 Um or more and 50 m or less, and more preferably 10 or more and 40 / zm or less.
- the thickness of the charge transport layer 16 is less than 5 zm, the charge retention ability of the photoreceptor surface decreases.
- the thickness of the charge transport layer 16 exceeds 50 m, the resolution of the photoreceptor decreases. Therefore, it was set to 5 m or more and 50 m or less.
- the photosensitive layer 14 may be further added with one or more electron accepting substances or dyes in order to improve the sensitivity and suppress an increase in residual potential and fatigue due to repeated use.
- acid anhydrides such as succinic anhydride, maleic anhydride, phthalic anhydride and 4-chloronaphthalic anhydride; cyano compounds such as tetracyanoethylene and terephthalmalon dinitrile; Aldehydes such as aldehydes, anthraquinones such as anthraquinone and 1-nitroanthraquinone, 2,4,7-trinitrofluorenone and 2,4,5,7-
- a polycyclic or heterocyclic compound such as tetranitrofluorenone, an electron-withdrawing material such as a diphenoquinone compound, or a high-molecular-weight material of these electron-withdrawing materials can be used.
- an organic photoconductive dye such as a xanthene dye, a thiazine dye, a triphenylmethane dye, a quinoline pigment, or copper phthalocyanine can be used. These organic photoconductive compounds function as optical sensitizers.
- a protective layer may be provided on the surface of the photosensitive layer 14. By providing the protective layer, the printing durability of the photosensitive layer 14 can be improved, and at the same time, the photosensitive layer 14 such as ozone and nitrogen oxide generated by corona discharge when charging the surface of the photoconductor is charged. Chemical adverse effects can be prevented.
- the protective layer for example, a layer made of a resin, a resin containing an inorganic filler or an inorganic oxide is used.
- FIG. 2 is a schematic cross-sectional view schematically showing a configuration of an electrophotographic photosensitive member 2 according to another embodiment of the present invention.
- the electrophotographic photoreceptor 2 is similar to the electrophotographic photoreceptor 1 shown in FIG. 1, and the corresponding parts are denoted by the same reference numerals and description thereof will be omitted.
- an intermediate layer 18 is provided between the conductive support 11 and the photosensitive layer 14.
- Exposure reduces surface charges other than those to be erased, and may cause defects such as fogging in images.
- a toner image is formed in a portion where the surface charge has been reduced by exposure, so if the surface charge is reduced due to a factor other than exposure, the toner is left on a white background.
- Image fogging called black spots, where fine black spots are formed due to adhesion, occurs, and the image quality significantly deteriorates.
- the chargeability in a minute area is reduced due to a defect in the conductive support 11 or the photosensitive layer 14, and image fog such as black spots is generated, resulting in a remarkable image defect.
- the intermediate layer 18 as described above, it is possible to sense Since the injection of charges into the optical layer 14 can be prevented, the chargeability of the photosensitive layer 14 can be prevented from deteriorating. Generation of defects such as fogging can be prevented.
- the intermediate layer 18 defects on the surface of the conductive support 11 can be covered and a uniform surface can be obtained, so that the film forming property of the photosensitive layer 14 can be improved. Further, peeling of the photosensitive layer 14 from the conductive support 11 can be suppressed, and the adhesiveness between the conductive support 11 and the photosensitive layer 14 can be improved.
- a resin layer or an alumite layer made of various resin materials is used as the intermediate layer 18.
- the resin material forming the resin layer include polyethylene resin, polypropylene resin, polystyrene resin, acrylic resin, vinyl chloride resin, vinyl acetate resin, polyurethane resin, epoxy resin, polyester resin, melamine resin, silicone resin, and polyvierbutyra.
- Preferred alcohol-soluble nylon trees include, for example, so-called copolymerized nylons obtained by copolymerizing 6-nylon, 6,6-nylon, 6,10-nylon, 11-nylon and 2_nylon, and the like.
- copolymerized nylons obtained by copolymerizing 6-nylon, 6,6-nylon, 6,10-nylon, 11-nylon and 2_nylon, and the like.
- resins obtained by chemically modifying nylon such as N-alkoxymethyl-modified nylon and N-alkoxyethyl-modified nylon.
- the intermediate layer 18 may contain particles such as a metal oxide. By incorporating these particles, the volume resistance of the intermediate layer 18 can be adjusted to further prevent the injection of charges from the conductive support 11 to the photosensitive layer 14 and to be used in various environments. The electrical characteristics of the photoconductor can be maintained.
- metal oxide particles examples include titanium oxide, aluminum oxide, and zinc oxide. Mention may be made of particles such as luminium and tin oxide.
- the intermediate layer 18 contains particles such as metal oxide particles, for example, these particles are dispersed in a resin solution in which the above-mentioned resin is dissolved to prepare a coating liquid for an intermediate layer.
- the intermediate layer 18 can be formed by coating on the conductive support 11.
- Water or various organic solvents are used as the solvent for the resin solution.
- single solvents such as water, methanol, ethanol or butanol, or water and alcohols, two or more alcohols, acetone or dioxolane and the like, alcohols, dichloroethane, chloroform and trichloroethane, etc.
- a mixed solvent such as a chlorine-based solvent and an alcohol is preferably used.
- a general method using a pole mill, a sand mill, an attritor, a vibration mill, an ultrasonic disperser, or the like can be used.
- the total content c of the resin and the metal oxide in the coating solution for the intermediate layer is C / D in a mass ratio of 1Z99 to 40/60 with respect to the content D of the solvent used in the coating solution for the intermediate layer. And more preferably 2Z98 to 30Z70.
- the ratio of the resin to the metal oxide (resin / metal oxide) is preferably 90Z10 to 1Z99 by mass, more preferably 7030 to 5Z95.
- Examples of the method for applying the coating solution for the intermediate layer include a spray method, a vacuum coating method, a roll coating method, a blade method, a ring method, and a dip coating method.
- the dip coating method is relatively simple and excellent in productivity and cost as described above, it is often used for forming the intermediate layer 18.
- the thickness of the intermediate layer 18 is preferably 0.01 m or more and 20 xm or less, and more preferably 0.05 zzm or more and 10 xm or less. When the thickness of the intermediate layer 18 is less than 0.01 xm, the intermediate layer 18 does not substantially function as a conductive support.
- FIG. 3 is a schematic cross-sectional view showing a simplified configuration of an electrophotographic photosensitive member 3 according to still another embodiment of the present invention.
- the electrophotographic photoreceptor 3 is similar to the electrophotographic photoreceptor 2 shown in FIG. 2, and corresponding portions are denoted by the same reference numerals and description thereof will be omitted.
- the electrophotographic photoreceptor 3 has a single-layer photosensitive layer 14 in which both the charge generating substance 12 and the charge transporting substance 13 are contained in the binder resin 17. That is, it is a layer type photoreceptor.
- the photosensitive layer 14 is formed in the same manner as in forming the charge transport layer 13 described above.
- the charge generation material 13 described above, the charge transport material 13 containing the organic photoconductive material of the present invention represented by the general formula (1), for example (2), and the binder resin 17 are It is formed by dissolving or dispersing in a suitable solvent to prepare a coating solution for a photosensitive layer, and applying the coating solution for a photosensitive layer onto the intermediate layer 18 by a dip coating method or the like.
- the ratio of the charge transport material 13 in the photosensitive layer 14 to the binder resin 17 is the same as the ratio of the charge transport material 13 in the charge transport layer 16 to the binder resin 17 and the mass ratio, similar to AZB. And 10Z12 ⁇ : L0Z30.
- the thickness J3 of the photosensitive layer 14 is preferably 5 m or more and 100 zm or less, more preferably 10 m or more and 50 zm or less. If the thickness of the photosensitive layer 140 is less than 5 m, the charge retention ability of the photoreceptor surface is reduced. When the thickness of the photosensitive layer 140 exceeds 100 m, the productivity is reduced. Therefore, it was set to 5 or more and 100 or less.
- the electrophotographic photoreceptor according to the present invention is limited to the configuration shown in FIGS. 1 to 3 described above. Various layer configurations can be adopted without being performed.
- antioxidants include phenolic compounds, hydroquinone compounds, tocopherol compounds, and amine compounds. be able to. These antioxidants are preferably used in an amount of 0.1% by mass or more and 50% by mass or less based on 13 of the charge transporting substance.
- the amount of the antioxidant is less than 0.1% by mass, it is not possible to obtain a sufficient effect for improving the stability of the coating solution and the durability of the photoreceptor. If the amount of the antioxidant exceeds 50% by mass, the properties of the photoreceptor are adversely affected. Therefore, the content is set to 0.1% by mass or more and 50% by mass or less.
- FIG. 4 is a simplified diagram showing the configuration of an image forming apparatus including the electrophotographic photosensitive member according to the present invention.
- the image forming apparatus 5 includes an electrophotographic photoconductor 10 (hereinafter, also simply referred to as “photoconductor 10”) according to the present invention.
- the photoconductor 10 has a cylindrical shape, and is driven to rotate at a predetermined peripheral speed in the direction of reference numeral 41 by a driving unit (not shown).
- a charger 32, a semiconductor laser (not shown), a developing device 33, a transfer charger 34, and a cleaner 36 are arranged along the rotation direction of the photoconductor 10. They are provided in order.
- a fixing device 35 is provided in the traveling direction of the transfer paper 51.
- the surface 4 3 facing the charger 3 2 is Or, it receives a uniform negative charge of a predetermined potential.
- a laser beam 31 is irradiated from a semiconductor laser (not shown), and the surface 43 of the photoconductor 10 is exposed.
- the laser beam 31 is repeatedly scanned in the longitudinal direction of the photoreceptor 10 which is the main scanning direction, and an electrostatic latent image is sequentially formed on the surface 43 of the photoreceptor 10.
- the electrostatic latent image is developed as a toner image by a developing unit 33 provided downstream of the image forming point of the laser beam 31 in the rotation direction.
- the transfer paper 51 is supplied to the transfer charger 34 provided on the downstream side in the rotation direction of the developing device 33 from the direction of reference numeral 42.
- the toner image formed on the surface 43 of the photoconductor 10 in the developing device 33 is transferred onto the surface of the transfer paper 51 by the transfer charger 34.
- the transfer paper 51 onto which the toner image has been transferred is conveyed to a fixing device 35 by a conveyance belt (not shown), and the toner image is fixed on the transfer paper 51 by the fixing device 35, and a part of the image is formed. You.
- the toner remaining on the surface 43 of the photoreceptor 10 is supplied to a cleaner 3 provided with a static elimination lamp (not shown) further downstream of the transfer charger 34 in the rotational direction and upstream of the charger 32 in the rotational direction. Removed by 6.
- the above process is repeated by further rotating the photoreceptor 10 to form an image on the transfer paper 51.
- the transfer paper 51 on which the image is formed in this way is discharged outside the image forming apparatus 5.
- the electrophotographic photoreceptor 10 provided in the image forming apparatus 5 contains the organic photoconductive material of the present invention represented by the general formula (1), for example, (2) as a charge transporting substance. Therefore, it has a high charged potential, is highly sensitive, shows sufficient photoresponsiveness, has excellent durability, and its characteristics do not deteriorate even when used in a low-temperature environment or in a high-speed process.
- the obtained compound was analyzed by liquid chromatography-mass spectrometry (B: LC-MS).
- the enamine intermediate represented by the following structural formula (10) (calculated molecular weight: 397.18) was converted to proton Correspond to the molecular ion [M + H] + The peak was observed at 398.4, indicating that the obtained compound was an enamine intermediate represented by the following structural formula (10) (yield: 88%).
- the result of LC-MS analysis showed that the purity of the obtained enamine intermediate was 99.1%.
- diphenylacetate represented by the structural formula (9) which is an aldehyde compound
- reaction solution was allowed to cool and gradually added to 800 ml of a cooled 4N (4N) aqueous sodium hydroxide solution to cause precipitation.
- the resulting precipitate was separated by filtration, washed sufficiently with water, and recrystallized with a mixed solvent of ethanol, ethyl acetate and 5 to obtain 19.2 g of a yellow powdery compound.
- the obtained compound was analyzed by LC-MS, and as a result, it was represented by the following structural formula (11).
- the peak corresponding to the molecular ion [M + H] + in which a proton was added to the enamine-bisaldehyde intermediate was observed at 454.1. It was found to be an enamine-aldehyde intermediate represented by the structural formula (11) (yield: 85%).
- the result of the LC-MS analysis showed that the purity of the obtained enamine-aldehyde intermediate was 99.2%. .
- the enamine intermediate represented by the structural formula (10) is subjected to formylation by a Vilsmeier reaction to obtain an enamine-bisaldehyde intermediate represented by the structural formula (11). I was able to.
- the toluene solution was transferred to a separating funnel, washed with water, and the organic layer was taken out. The organic layer taken out was dried over magnesium sulfate. After drying, the organic layer from which solids were removed was concentrated and subjected to silica gel column chromatography to obtain yellow crystals. 7 g were obtained.
- FIG. 5 is a 1 H-NMR spectrum of the product of Production Example 1-3
- FIG. 6 is a 13 C-NMR spectrum of the product of Production Example 1-3 obtained by ordinary measurement
- FIG. 7 is a production example.
- 13 is a 13 C-NMR spectrum of 13 products measured by DEPT 135.
- the value described between the signal and the horizontal axis is a relative integrated value of each signal.
- This charge generation layer coating solution is applied on a conductive support 11, which is an 80-mm-thick polyester film of aluminum on which aluminum is vapor-deposited on the surface, and then dried, followed by drying.
- the charge generation layer 15 having a thickness of 0.3 m was formed.
- Example 2 The same procedure as in Example 1 was repeated except that the charge transporting substance 13 was replaced by Exemplified Compound No. 28 and the enamine compounds of Exemplified Compounds Nos. 5, 30, 39, and 46 shown in the table were used. An electrophotographic photosensitive member was manufactured.
- An electronic device was produced in the same manner as in Example 1 except that the comparative compound A represented by the following structural formula (16) was used as the charge transporting substance 13 in place of Exemplified Compound No. 28.
- An electrophotographic photoreceptor was produced in the same manner as in Example 1, except that the charge transport material 13 was replaced with the comparative compound B represented by the following structural formula (17) in place of the exemplified compound No. 28.
- An electrophotographic photoreceptor was prepared in the same manner as in Example 1, except that the charge transport material 13 was replaced with the comparative compound C represented by the following structural formula (18) in place of the exemplary compound No. 28. (However, after the sample was manufactured / dried, countless microcrystals due to poor compatibility of Comparative Compound C appeared on the sheet surface, and the electrical characteristics could not be evaluated satisfactorily. )
- An electrophotographic photoreceptor was produced in the same manner as in Example 1, except that Comparative Compound D represented by the following structural formula (19) was used instead of Exemplified Compound No. 28 as the charge transporting substance 13.
- Ionization potential using a surface analyzer (AC-1 manufactured by Riken Keiki Co., Ltd.) was measured. Gold was vapor-deposited on the surface of the photosensitive layer of each electrophotographic photoreceptor, and the charge mobility of the charge transport material 13 was measured at room temperature and under reduced pressure by the time-of-flight (Time_of-Fligt) method. Table 17 shows the measurement results. Note that the values of the charge mobility shown in Table 17 are values when the electric field strength is 2.5 ⁇ 10 5 V / cm.
- the organic photoconductive material of the present invention represented by the general formula (1) may be a comparative compound A, which is a conventionally known charge transport material, or Was found to have more than two orders of magnitude higher charge mobility than enamine styryl compounds such as B and triphenylamine dimers (abbreviation: TPD) such as comparative compound D.
- enamine bisbutadiene compound of the comparative compound C having a very high symmetry, a myriad of microcrystals due to poor compatibility of the present compound appear on the sheet surface, and the electrical characteristics can be evaluated satisfactorily. could not.
- Aluminum oxide (chemical formula: A 1 2 0 3) and zirconium dioxide (Formula
- TO-D-1) 9 parts by mass and copolymerized nylon resin (Toray Industries, Inc .: CM8000 ) 9 parts by mass was added to a mixed solvent of 41 parts by mass of 1,3-dioxolane and 41 parts by mass of methanol, and dispersed for 12 hours using a paint shear to prepare a coating solution for an intermediate layer.
- the prepared coating solution for an intermediate layer is applied on a 0.2 mm thick aluminum substrate serving as the conductive support 11 by a vacuum coating method, and then dried to form an intermediate layer 18 having a thickness of 1 zm. Formed. +
- the resultant was dried to form a charge transport layer 16 having a thickness of 18 / im.
- Example 7 In the same manner as in Example 7 except that the charge transporting substance 13 was replaced with the exemplified compound No. 28 and the enamine compounds of the exemplified compounds Nos. 5, 16, 18, 29, and 47 shown in Tables 1 to 16, respectively. Thus, five types of electrophotographic photosensitive members were produced.
- the charge transport material 13 was replaced with the comparative compound D represented by the structural formula (19) or the comparative compound D represented by the structural formula (19) in place of the exemplary compound No. 28.
- the comparative compound D represented by the structural formula (19) represented by the structural formula (19) in place of the exemplary compound No. 28.
- two types of electrophotographic photosensitive members were produced.
- a coating solution for an intermediate layer was prepared in the same manner as in Example 7, applied to a 0.2 mm-thick aluminum substrate serving as the conductive support 11, and then dried to form an intermediate layer 18 having a film thickness. Formed.
- An electrophotographic photoreceptor was produced in the same manner as in Example 7, except that an X-type metal-free phthalocyanine was used instead of the azo compound represented by the structural formula (20) as the charge generating substance 12. (Examples 15 to 19)
- X-type metal-free phthalocyanine was used in place of the azo compound represented by the structural formula (20) as the charge generating substance 12, and the charge transporting substance 13 was replaced with Exemplified Compound No. 28 in Tables 1 to 16.
- Five kinds of electrophotographic photoreceptors were produced in the same manner as in Example 7, except that the enamine compounds of the exemplified compounds Nos. 2, 24, 36, 72, and 79 were used.
- the evaluation of the initial characteristics was performed as follows.
- the surface of the photoconductor is charged by applying a negative (-) 5 kV voltage to the photoconductor. (V).
- V negative
- a plus (+) voltage of 5 kV was applied.
- the charged photoreceptor surface was exposed.
- the surface potential of the photoconductor is set to the charged potential V.
- the energy required to reduce the energy by half was measured as the half-life exposure amount E 1/2 (J cm 2 ).
- the evaluation index of the degree was used.
- the surface potential of the photoreceptor 10 seconds after the start of exposure was measured as a residual potential (V), and was used as an evaluation index for photoresponsiveness.
- the exposure was performed using the azo compound represented by the structural formula (20) as the charge generating substance 12 in the case of the photoconductors of Example 7 13 and Comparative Example 56.
- the wavelength 7 Light with an exposure energy of 1 W / cm 2 was used.
- the evaluation of the repeatability was performed as follows. After repeating the above-described charging and exposure operations as one cycle for 50,000 times, the half-exposure amount E i / 2 , the charged potential V 0 and the residual potential V r were measured in the same manner as in the evaluation of the initial characteristics.
- the organic light-emitting material of the present invention represented by the general formula (1) was added to the charge transporting substance 13.
- the photoconductors of Examples 7 to 12 and 14 to 19 using the conductive material are more charge-transporting materials 13 than the photoconductors of Comparative Examples 5 to 8 using the comparative compound A or D. It was found that the half-life exposure '5 amount E 1/2 was small and high sensitivity, and the residual potential Vr was low in the negative direction, that is, the potential difference from the residual potential V reference potential was small, and the photoresponsiveness was excellent. It was also found that this property was maintained even after repeated use, and was also maintained in a low-temperature, low-humidity (LZL) environment.
- LZL low-temperature, low-humidity
- a coating solution for a generating layer was prepared.
- This charge generation layer coating solution is applied to the previously formed intermediate layer 18 in the same manner as the previously formed intermediate layer 18, that is, by a dip coating method, to obtain a film thickness of 0.4 m.
- the charge generation layer 15 was formed on the intermediate layer 18.
- a coating solution for a charge transport layer was prepared.
- the coating solution for the charge transport layer is applied onto the previously formed charge generation layer 15 by the same dip coating method as the previously formed intermediate layer 18, and then dried at 110 ° C for 1 hour.
- a charge transport layer 16 having a thickness of 23 m was formed.
- an electrophotographic photosensitive member was manufactured.
- An electrophotographic photoreceptor was produced in the same manner as in Example 21 except that the charge transporting substance 13 was replaced with the comparative compound A represented by the structural formula (16) in place of the exemplary compound No. 28. .
- An electrophotographic photosensitive member was manufactured in the same manner as in Example 20, except that the amount of the polycarbonate resin as the binder resin 17 of the charge transport layer 16 was changed to 25 parts by mass.
- the amount of the polycarbonate resin which is the binder resin 17 of the charge transport layer 16 was 25 parts by mass, and the charge transport material 13 was replaced with the exemplary compound No. 28, and the exemplary compound No. 15 or 33 shown in Tables 3 and 7 was used.
- Example 2 except that the enamine compound of Example 2 was used.
- An electrophotographic photosensitive member was manufactured in the same manner as in Example 20, except that the amount of the polycarbonate resin as the binder resin 17 of the charge transport layer 16 was changed to 10 parts by mass.
- An electrophotographic photoreceptor was manufactured in the same manner as in Example 20, except that the amount of the poly-carbonate resin as the binder resin 17 of the charge transport layer 16 was changed to 31 parts by mass.
- Example 20 when the charge transport layer 16 was formed, the same amount of tetrahydrofuran as in Example 20 could not be used to prepare a coating solution for the charge transport layer in which the polycarbonate resin was completely dissolved. A charge transport layer coating solution in which one-ponate resin was completely dissolved was prepared, and this was used to form a charge transport layer 16.
- a surface electrometer (CATE751 manufactured by Gentec) is installed inside the copier to measure the surface potential of the photoreceptor during the image forming process, and is charged in an N / N environment of 22 ° C / 65% RH.
- the charging potential V which is the surface potential immediately after. (V) and the surface potential V L (V) immediately after exposure with a laser beam were measured. Also 5 Similarly, in a L / L environment of ° C / 20% RH, the surface potential VL immediately after exposure with laser light was measured.
- the surface potential VL measured under N / N environment and then V (1), when the surface potential V L were measured under the L / L environment and the V L (2), V L (1) and V L ( 2) the difference between the potential variation Z ⁇ V L ( V L (2) -V L (1)) and was determined, and the stability of the metrics of the electrical characteristics.
- the photoreceptor surface was charged by a negative charging process.
- the ratio AZB is 10/10, which exceeds 10/12, It was found that the film loss was smaller and the printing durability was higher than that of the photoconductor of Reference Example 1 in which the ratio of the solder resin was low.
- the charge transport layer by forming the charge transport layer by incorporating the organic photoconductive material of the present invention, it was possible to improve the printing durability of the charge transport layer without lowering the photoresponsiveness. .
- the organic photoconductive material has a specific structure, that is, the substituent of the minenamine moiety is an aryl or heterocyclic group, and has an asymmetric bis-butene or triene structure. Accordingly, it is possible to provide an organic photoconductive material having high charge mobility, which has excellent compatibility with the binder resin and does not cause problems such as deposition of the charge transport material during film formation.
- the organic photoconductive material since the organic photoconductive material has a specific structure, an organic photoconductive material having particularly high charge mobility can be easily provided.
- the photosensitive layer contains an organic photoconductive material having high charge mobility as a charge transporting substance, so that the photosensitive layer has high charge potential, high sensitivity, and sufficient photoresponsiveness.
- the photosensitive layer contains oxotitanium phthalocyanine, which is a charge generating substance having high charge generation efficiency and charge injection efficiency, and therefore has high sensitivity and high resolution.
- An electrophotographic photosensitive member can be provided.
- the photosensitive layer has a laminated structure of a charge generating layer containing a charge generating substance and a charge transporting layer containing a charge transporting substance.
- An electrophotographic photoreceptor having high stability and high durability can be provided.
- the present invention even when a binder resin is added at a higher ratio than in the case of using a conventionally known charge transporting substance, the light responsiveness can be maintained. Without lowering, the printing durability of the charge transport layer can be improved, and the durability of the electrophotographic photoreceptor can be improved.
- the chargeability of the photosensitive layer is prevented from lowering, and the occurrence of defects such as fog on the image is prevented.
- the film forming property of the photosensitive layer and the adhesion between the conductive support and the photosensitive layer can be improved.
- the charged potential is high, the sensitivity is high, sufficient photoresponsiveness is exhibited, the durability is excellent, and the characteristics are not deteriorated even when used in a low-temperature environment or in a high-speed process.
- Highly reliable electrophotographic photoreceptor that does not degrade its characteristics even when exposed to light, providing highly reliable images that can provide high-quality images in various environments
- the image forming apparatus can be provided, and at the same time, deterioration of image quality due to exposure of the photoconductor to light during maintenance or the like can be prevented, and the reliability of the image forming apparatus can be improved.
- the organic photoconductive material of the present invention has a high charge potential, high sensitivity, sufficient photoresponse, and does not cause adverse effects such as partial crystallization during film formation.
- a highly reliable electrophotographic photoreceptor that does not deteriorate even when used in a low-temperature environment or in a high-speed process, and does not deteriorate even when exposed to strong light It is possible and has high industrial applicability.
- electrophotographic photoreceptors and image forming apparatuses using the organic photoconductive material have high industrial applicability.
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Abstract
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Also Published As
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JP2004334125A (ja) | 2004-11-25 |
US20060204871A1 (en) | 2006-09-14 |
US7416824B2 (en) | 2008-08-26 |
CN100485536C (zh) | 2009-05-06 |
JP3580426B1 (ja) | 2004-10-20 |
CN1788240A (zh) | 2006-06-14 |
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