JP6051685B2 - Electrophotographic photosensitive member, image forming method using the same, image forming apparatus, and process cartridge for image forming apparatus - Google Patents

Description

  The present invention is a highly durable electrophotographic photosensitive member (hereinafter referred to as “photosensitive member”, “electrostatic latent image”) that has extremely high wear resistance during repeated use and can maintain high image quality with few image defects over a long period of time. The present invention also relates to an image forming method, an image forming apparatus, and a process cartridge using the electrophotographic photosensitive member.

  In recent years, organic photoconductors (OPCs) have good performance and are widely used in copying machines, facsimiles, laser printers, and their combined machines instead of inorganic photoconductors because of various advantages. The reasons for this are, for example, (1) optical characteristics such as light absorption wavelength range and absorption amount, (2) electrical characteristics such as high sensitivity and stable charging characteristics, and (3) selection of materials. Examples include a wide range, (4) ease of production, (5) low cost, and (6) non-toxicity.

Recently, in order to reduce the size of the image forming apparatus, the diameter of the photoconductor has been reduced, and further, the high speed of the machine and the maintenance-free movement have been added. ing. From this point of view, organic photoreceptors are generally soft because the charge transport layer is mainly composed of a low molecular charge transport material and an inert polymer, and when used repeatedly in an electrophotographic process, a development system or a cleaning system There is a drawback that wear is likely to occur due to the mechanical load due to.
In addition, due to the demand for higher image quality, the toner particles have been reduced in size, and with this, in order to improve the cleaning performance, the rubber hardness of the cleaning blade and the contact pressure must be increased. The This is also one of the factors that promote the wear of the photoreceptor. Such wear of the photoreceptor deteriorates electrical characteristics such as sensitivity deterioration and chargeability, and causes abnormal images such as image density reduction and background stains. In addition, scratches in which wear locally occurs result in streak-like stain images due to poor cleaning.

  Accordingly, various improvements have been made for the purpose of improving the wear resistance of the organic photoreceptor. For example, a material using a curable binder in the charge transport layer (see Patent Document 1), a material using a polymer type charge transport material (see Patent Document 2), or a material in which an inorganic filler is dispersed in the charge transport layer (Patent Document) Reference 3), a polyfunctional acrylate monomer cured product (see Patent Document 4), a monomer having a carbon-carbon double bond, a charge transport material having a carbon-carbon double bond, and a binder resin A charge transporting layer formed using a coating liquid (see Patent Document 5), and a compound obtained by curing a hole transporting compound having two or more chain polymerizable functional groups in the same molecule. (Refer to Patent Document 6), those using colloidal silica-containing curable silicone resin (refer to Patent Document 7), and organosilicon modified hole transporting compound bonded to curable organosilicon polymer. One provided with a fat layer (see Patent Documents 8 and 9), one obtained by curing a curable siloxane resin having a charge transporting group (see Patent Document 10), and at least one hydroxyl group A substance containing a charge transporting substance, a three-dimensionally cross-linked resin and conductive fine particles (see Patent Document 11), a reactive charge transporting substance, a polyol having at least two or more hydroxyl groups, and an aromatic isocyanate compound Containing a crosslinkable resin formed by crosslinking with (refer to Patent Document 12), containing a charge transporting material having at least one hydroxyl group and a three-dimensionally crosslinked melamine formaldehyde resin (patent) Reference 13), containing a charge transporting substance having a hydroxyl group and a three-dimensionally cross-linked resol type phenol resin (see Patent Reference 14) ), And the like.

Further, selected from a photofunctional organic compound capable of forming a cured film, a sulfonic acid and / or derivative thereof, and an amine having a boiling point of 250 ° C. or lower (see Patent Document 15), a guanamine compound and a melamine compound. And a coating liquid containing at least one charge transporting material having at least one substituent selected from —OH, —OCH ₃ , —NH ₂ , —SH, and —COOH. A solid content concentration in the at least one coating liquid selected from a guanamine compound and a melamine compound is 0.1% by mass or more and 5% by mass or less, and at least of the charge transporting material. Examples include one having a solid content concentration of 90% by mass or more in one type of the coating liquid (see Patent Document 16).

  Among these prior arts, those in which a three-dimensionally crosslinked surface layer is formed are most excellent in mechanical durability and are advantageous in extending the life of the photoreceptor. For example, the one described in Patent Document 6 can form a three-dimensional cross-linked film radically polymerized by ultraviolet rays or electron beams, and exhibits excellent wear resistance. However, since ultraviolet irradiation and electron beam irradiation are necessary, a large-scale apparatus is required, causing problems in terms of productivity, and the charge transporting compound deteriorates due to the irradiation, and the potential characteristics of the photoreceptor are deteriorated. There is a problem such as. On the other hand, Patent Documents 12 to 16 capable of forming a three-dimensional crosslinked film by thermosetting are advantageous in terms of productivity, and can provide a photoconductor excellent in wear resistance. However, in patent document 12, it becomes a hardened | cured material by a urethane bond, its charge transport property is bad, and use is difficult from the point of an electrical property. Patent Documents 13 to 16 have a surface layer three-dimensionally cross-linked between a charge transporting compound having a polar group such as a hydroxyl group and a reactive active species such as melamine, and are relatively excellent in electrical characteristics. Especially the thing of patent document 16 is excellent in charge transportability, since a charge transportable compound can be used in high concentration of 90% or more, and shows a favorable sensitivity characteristic. However, polar groups such as hydroxyl groups possessed by the charge transporting compound are inevitably left in the three-dimensional crosslinked film, so that the charge is likely to be lowered, the image density in a high temperature and high humidity environment is likely to be lowered, or a charger is used. There is a drawback that the image density tends to be lowered by exposure to NOx gas or the like.

  On the other hand, there is also a proposal of using a compound having a charge transporting compound blocked with a hydroxyl group or the like and curing it with a reactive species such as melamine (Patent Document 17). In this case, it is possible to prevent the polar group from remaining, but it is difficult to form a three-dimensional crosslinked film having excellent mechanical properties because the reaction between the blocked hydroxyl group and the reactive species is difficult.

  As described above, it has excellent mechanical strength, excellent electrical characteristics (chargeability, charge transportability, residual potential characteristics), low environmental dependency, excellent gas resistance, and truly long life and stability. It has not been possible to provide a highly durable photoconductor that can output an image and is excellent in productivity.

As an electrophotographic photoreceptor that can stably output high-quality images over a long period of time, it has excellent mechanical durability (wear resistance, scratch resistance, etc.) and excellent electrical properties (charging stability, sensitivity stability, residual The potential characteristics, etc.), excellent environmental stability (especially under high temperature and high humidity), and excellent gas resistance (NOx, etc.) must be satisfied over time.
This invention is made | formed in view of this present condition, and makes it a subject to solve the said various problems in the past and to achieve the following objectives. That is, the present invention has excellent mechanical durability (wear resistance, scratch resistance, etc.), excellent electrical characteristics (charging stability, sensitivity stability, residual potential characteristics, etc.), excellent environment for repeated use. An object of the present invention is to provide a highly durable electrophotographic photosensitive member that exhibits stability (particularly under high temperature and high humidity), excellent gas resistance (NOx, etc.), and can maintain high image quality with few image defects over a long period of time. To do.

As a result of intensive studies to solve the above problems, the present inventors have made the surface layer of the electrophotographic photoreceptor a three-dimensional crosslinked film in which a specific charge transporting compound is polymerized by a specific acid catalyst. The present inventors have found that the above-described problems can be solved, and have reached the present invention.
That is, the present invention is as follows.
Have at least a photosensitive layer on an electroconductive substrate, in the manufacturing method of the electrophotographic photosensitive member outermost surface layer is made of three-dimensionally crosslinked film of the photosensitive layer, the three-dimensional crosslinked film, a vinyl sulfonic acid and an amine A vinylsulfonic acid amine salt obtained by reaction, having a pH of 4 or more and 7 or less in 0.01 mol / l aqueous solution of the vinylsulfonic acid amine salt as an acid catalyst, and having an aromatic ring the compound having charge aromatic ring of transporting compound [(tetrahydro -2H- pyran-2-yl) oxy] 3 or more methyl groups, by the acid catalyst, the [(tetrahydro -2H- pyran-2-yl )] A method for producing an electrophotographic photosensitive member , characterized in that it is formed by a reaction in which part of a methyl group is cut off and polymerized.

  According to the present invention, excellent mechanical durability (wear resistance, scratch resistance, etc.), excellent electrical characteristics (charging stability, sensitivity stability, residual potential characteristics, etc.), excellent environmental stability against repeated use It is possible to provide a highly durable electrophotographic photosensitive member that exhibits high performance (particularly under high temperature and high humidity) and excellent gas resistance (NOx, etc.) and can maintain high image quality with few image defects over a long period of time.

It is the infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 1, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is the infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 2, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 3, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 4, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 5, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 6, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 7, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 8, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is the infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 9, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 10, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 11, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is the infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 12, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is the infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 13, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is the infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 14, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 15, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 16, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is the infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 17, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 18, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is the infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 19, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is an infrared absorption spectrum figure (measured on a NaCl plate) of the compound obtained in Synthesis Example 20, the horizontal axis indicates the wave number (cm ⁻¹ ), and the vertical axis indicates the transmittance (%). It is the infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 21, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 22, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is the result of differential thermogravimetry (TG / DTA) of the compound obtained in Synthesis Example 15, the horizontal axis indicates the temperature (° C.), the vertical axis (principal axis) is the weight reduction rate (%), and the vertical axis (first (Axis) shows heat flow (μV). It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 23, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows a transmittance | permeability (%). It is the schematic which shows an example of the laminated constitution of the electrophotographic photoreceptor of this invention. It is the schematic which shows another example of the layer structure of the electrophotographic photoreceptor of this invention. It is the schematic which shows another example of the layer structure of the electrophotographic photoreceptor of this invention. It is the schematic which shows another example of the layer structure of the electrophotographic photoreceptor of this invention. It is the schematic which shows another example of the layer structure of the electrophotographic photoreceptor of this invention. 1 is a schematic diagram illustrating an image forming apparatus and an electrophotographic process of the present invention. 1 is a schematic diagram illustrating a tandem full-color image forming apparatus according to the present invention. It is the schematic explaining an example of the process cartridge of this invention. It is a figure showing the result of the X-ray-diffraction spectrum of the titanyl phthalocyanine powder produced in the Example.

  The electrophotographic photosensitive member according to the present invention is an electrophotographic photosensitive member having at least a photosensitive layer on a conductive support, wherein the outermost surface layer of the photosensitive layer is attached to the aromatic ring of the charge transporting compound having an aromatic ring [ A compound having three or more (tetrahydro-2H-pyran-2-yl) oxy] methyl groups is cleaved by a part of the [(tetrahydro-2H-pyran-2-yl) oxy] methyl group by an acid catalyst. It is composed of a polymerized three-dimensional crosslinked membrane, and the acid catalyst is a sulfonic acid amine salt obtained by reacting a sulfonic acid with an amine, and the pH of the sulfonic acid amine salt in a 0.01 mol / l aqueous solution is 4 or more and 7 It is characterized by the following.

Here, the compound having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring of the charge transporting compound is insoluble in an organic solvent or the like by using an appropriate catalyst and has a crosslinking density. It has been found that a high three-dimensional crosslinked film can be formed, which is the basis of the present invention. This reaction was found to be a reaction in which a part of the [(tetrahydro-2H-pyran-2-yl) oxy] methyl group was cut off and polymerized from infrared absorption spectra and weight loss before and after the reaction.
Furthermore, the three-dimensional crosslinked film obtained by using a sulfonic acid amine salt having a specific pH as the acid catalyst has particularly excellent mechanical durability (abrasion resistance, scratch resistance, etc.) and excellent electrical characteristics (charging). Stability, sensitivity stability, residual potential characteristics, etc.), excellent environmental stability (especially under high temperature and high humidity), and excellent gas resistance (NOx, etc.).

Sulfonic acid has a high catalytic activity and can form a three-dimensional crosslinked film having a high crosslinking density. However, it remains as a highly polar component in the cured three-dimensional crosslinked film, and the image density is reduced due to charge reduction or exposure to NOx gas. There was a problem that it was likely to cause a decrease.
On the other hand, the sulfonic acid amine salt has a structure in which sulfonic acid is blocked with an amine. When the sulfonic acid is blocked with an amine, the catalytic activity is lowered at room temperature. However, when heated, the dissociation equilibrium of the sulfonic acid amine salt is inclined in the dissociation direction, and a catalytic activity comparable to that of the sulfonic acid is exhibited. In the present invention, by using a sulfonic acid amine salt having a pH of 4 or more and 7 or less when a 0.01 mol / l aqueous solution is used, mechanical durability, electrical characteristics, environmental stability, and gas resistance are at a high level. It was found that a compatible three-dimensional crosslinked film can be obtained.

The mechanism is not clear, but is estimated as follows. That is, the amine is dissociated from the sulfonic acid amine salt upon heating to exhibit catalytic activity, and a three-dimensional crosslinked film having a high crosslinking density is formed. And after heating, a sulfonic acid and an amine form a salt again and an acid component is neutralized, Therefore The three-dimensional crosslinked film excellent in an electrical property, environmental stability, and gas resistance is obtained. It is clear from the thermogravimetric analysis result of the sulfonic acid amine salt described below that the amine dissociated from the sulfonic acid amine salt does not volatilize even when heated and remains in the film.
Furthermore, the low catalytic activity at room temperature is effective in terms of coating solution stability, and an electrophotographic photoreceptor having excellent characteristics can be provided stably.

  When the pH of the sulfonic acid amine salt is less than 4, it indicates that the sulfonic acid and the amine are difficult to form a salt, and the sulfonic acid is not efficiently neutralized after curing, and environmental stability and gas resistance Tend to decrease. Also, since sulfonic acid is a strong acid, it is unlikely that the pH of the sulfonic acid amine salt obtained as a neutralized product with amine will be higher than 7. If the pH is higher than 7, it is considered that the amine is excessively contained in addition to the sulfonic acid amine salt. In such a case, it is due to the inhibition of curing or the tendency of the amine to remain in the film. May cause deterioration of electrical characteristics.

It has been conventionally known that a (tetrahydro-2H-pyran-2-yl) group is used as a protecting group for a hydroxyl group. For example, it has been widely described in Patent Document 17; Although cured products obtained by the reaction of a compound having a reactive active species such as melamine have been studied, there is no example of forming a crosslinked film with a protective group alone.
In addition, it can be obtained by thinking that the protecting group is removed from the idea of the protecting group and reacting, and the [(tetrahydro-2H-pyran-2-yl) oxy] methyl group is changed to a methylol group and reacts. The three-dimensional cross-linked film is the same as the cross-linked film of the methylol body. However, as a result of the examination, it was found that the reaction occurred without going through the methylol group, and therefore, [(tetrahydro-2H-pyran-2 -Yl) oxy] methyl group remains intact. Thus, the presence of [(tetrahydro-2H-pyran-2-yl) oxy] methyl group in the crosslinked membrane structure also affects the film physical properties, and the methylol body in the gas permeability affecting the gas resistance. There is a merit that it is smaller than the cross-linked cured product.

  As described above, the charge transporting compound is composed of a three-dimensional crosslinked film formed by a polymerization reaction of a compound having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring, and By using a three-dimensional crosslinked film using a sulfonic acid amine salt as the outermost surface layer of the photoreceptor, it has excellent charging stability and NOx resistance, and is excellent in mechanical durability and environmental stability. A photoreceptor is provided. In addition, since it is a cured product of only a charge transporting compound, it exhibits good charge transportability and yet does not contribute directly to charge transport such as [(tetrahydro-2H-pyran-2-yl) oxy] methyl group. Appropriately containing an active part also provides excellent charging stability, and since it does not contain a polar group such as a hydroxyl group, it also has excellent environmental stability and gas resistance. Provision becomes possible.

The three-dimensional crosslinked film in the electrophotographic photosensitive member of the present invention has a specific pH for a compound having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring of the charge transporting compound. The sulfonic acid amine salt is preferably added and heated to cause a polymerization reaction.
Heating using a curing catalyst allows the condensation reaction to proceed at a practical rate, and it is possible to form the outermost surface layer having excellent surface smoothness. When the surface smoothness is extremely deteriorated, the toner is also poorly cleaned, and an abnormal image is caused and high-quality printing cannot be performed. Therefore, it is possible to form a three-dimensional crosslinked film having excellent surface smoothness by heating at an appropriate temperature using an appropriate curing catalyst, and electrophotographic photosensitive member having the three-dimensional crosslinked film as the outermost surface layer of the photosensitive layer. The body will be able to print higher quality images over a long period of time.

Preferable examples of the sulfonic acid used for the synthesis of the sulfonic acid amine salt include organic sulfonic acids such as dodecylbenzenesulfonic acid, paratoluenesulfonic acid, and vinylsulfonic acid. Of these, paratoluenesulfonic acid or vinylsulfonic acid is more preferable.
Paratoluenesulfonic acid or vinylsulfonic acid has a high catalytic activity when dissociated from the sulfonic acid amine salt, and can form a three-dimensional crosslinked film having a high crosslinking density. Moreover, since it does not have a bulky substituent, it is easily neutralized by an amine after heating, and is excellent in coating solution stability and an effect of suppressing a decrease in image density.

The amine used for the synthesis of the sulfonic acid amine salt is preferably an amine represented by the following general formula (1).
(In the formula, R ₁ and R ₂ may be the same or different and each represents hydrogen or an alkyl group having 1 to 5 carbon atoms. R ₃ represents an alkyl group having 1 to 5 carbon atoms which may have a hydroxyl group. Show.)
In the amine represented by the general formula (1), a sterically bulky substituent such as a phenyl group or a naphthyl group is not directly bonded to a nitrogen atom. Excellent stability and suppression effect on image density reduction.

The compound having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring of the charge transporting compound is a charge transporting compound represented by the following general formula (2): Is preferred.
(In the formula, X ₁ is an alkylene group having 1 to 4 carbon atoms, an alkylidene group having 2 to 6 carbon atoms, a cycloalkylidene group having 5 or 6 carbon atoms, or an alkylidene having 2 to 6 carbon atoms via a phenylene group. A divalent group in which two groups are bonded, or an oxygen atom, Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ , Ar ₆ has 6 carbon atoms which may have an alkyl group as a substituent. To 18 aromatic hydrocarbon divalent groups.)
The compound represented by the general formula (2) has four [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring of the charge transporting compound, and is a non-conjugated linking group. also has a moderate molecular mobility that it has a X _1, part by polymerization reaction [(tetrahydro -2H- pyran-2-yl) oxy] 3-dimensionally crosslinked film leaving methyl groups forming the Therefore, it is possible to form a surface protective layer having a good balance between hardness and elastic properties of the completed three-dimensional crosslinked film, and being strong and excellent in both scratch resistance and wear resistance. Moreover, a relatively large oxidation potential of the molecule from structures of X _1, have the difficult to oxidize characteristics, is relatively stable even when the oxidizing gas such as ozone or NOx gas exposure, gas resistance It is possible to provide a photoreceptor that is strong against

The compound having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring of the charge transporting compound is a charge transporting compound represented by the following general formula (3) Is preferred.
(Wherein, X ₂ is _{-CH 2 -, - CH 2 CH} 2 -, - C (CH 3) 2 -Ph-C (CH 3) 2 -,
Or represents -O-. R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ may be the same or different and each represents a methyl group or an ethyl group, and o, p, q, r, s and t are 0 to 0 Represents an integer of 4. )
The compound represented by the general formula (3) is particularly excellent among the charge transporting compounds represented by the general formula (2), excellent in mutual polymerization reactivity, and similar to the general formula (2). The three-dimensional crosslinked film having a high crosslinking density can be formed.

In the electrophotographic photoreceptor according to the present invention, the photosensitive layer on the conductive support has at least a charge generation layer, a charge transport layer, and a crosslinkable charge transport layer in this order. The outermost surface layer is preferable.
The charge transport property of the three-dimensional crosslinked film in the electrophotographic photosensitive member of the present invention has the highest level of characteristics as compared with the conventional crosslinked film, but is still lower than that of a normal molecular dispersion type charge transport layer. . Therefore, when a conventional molecular dispersion type charge transport layer is used as the charge transport layer and a three-dimensional crosslinked film is used as a protective layer on the surface, the best performance is exhibited.
That is, by forming a thin cross-linked charge transport layer on a relatively thick normal molecular dispersion type charge transport layer, it is possible to provide an electrophotographic photoreceptor having the above characteristics without deteriorating sensitivity characteristics. Become. Therefore, the thickness of the cross-linked charge transport layer is preferably 1 to 10 μm.

The image forming method according to the present invention comprises a charging step for charging the surface of the electrophotographic photosensitive member, an exposure step for exposing the charged electrophotographic photosensitive member surface to form an electrostatic latent image, and the electrostatic latent image An image having at least a developing step for developing with a toner to form a visible image, a transferring step for transferring the visible image to a recording medium, and a fixing step for fixing the transferred image transferred to the recording medium It is a forming method, wherein the electrophotographic photosensitive member is the above-described electrophotographic photosensitive member of the present invention. Accordingly, it is possible to provide an image forming method that has high image stability during repeated use, can maintain a high image quality with few image defects over a long period of time, and is excellent in environmental stability and gas resistance.
In the image forming method of the present invention, it is preferable that the electrostatic latent image writing on the photoconductor in the exposure step is a digital image forming method. As a result, it is possible to provide an image forming method that can efficiently cope with a document and image production output on a PC and that has the same characteristics as the image forming method described above.

An image forming apparatus according to the present invention includes an electrophotographic photosensitive member, a charging unit that charges the surface of the electrophotographic photosensitive member, and an exposure unit that exposes the surface of the charged electrophotographic photosensitive member to form an electrostatic latent image. Developing means for developing the electrostatic latent image with toner to form a visible image; transfer means for transferring the visible image to a recording medium; and fixing the transferred image transferred to the recording medium. An image forming apparatus having at least a fixing unit, wherein the electrophotographic photosensitive member is the above-described electrophotographic photosensitive member of the present invention. Accordingly, it is possible to provide an image forming apparatus that has high image stability during repeated use, can maintain high image quality with few image defects over a long period of time, and is excellent in environmental stability and gas resistance.
In the image forming apparatus of the present invention, it is preferable that the electrostatic latent image is written on the photosensitive member by the exposure unit using a digital method. As a result, it is possible to provide an image forming apparatus that can efficiently cope with documents and image production output on a PC and has the same characteristics as the above-described image forming apparatus.

  The process cartridge according to the present invention has an electrophotographic photosensitive member and at least one means selected from the group consisting of a charging means, an exposure means, a developing means, a transfer means, a cleaning means, and a static elimination means, and an image forming apparatus main body In the process cartridge that is detachably mountable, the electrophotographic photosensitive member is the above-described electrophotographic photosensitive member of the present invention. As a result, it is possible to provide a process cartridge that has high image stability during repeated use and can maintain high image quality with few image defects over a long period of time, and is excellent in environmental stability and gas resistance.

Hereinafter, the electrophotographic photoreceptor of the present invention, the image forming method using the same, the image forming apparatus, and the process cartridge for the image forming apparatus will be described in detail.
The electrophotographic photosensitive member of the present invention is an electrophotographic photosensitive member having at least a photosensitive layer on a conductive support, wherein the outermost surface layer of the photosensitive layer is made of a specific sulfonic acid amine salt to form an aromatic ring of a charge transporting compound. And a three-dimensional crosslinked film formed by a polymerization reaction of a compound having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups.
The three-dimensional crosslinked membrane referred to here is composed of compounds having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring of the charge transporting compound, and [(tetrahydro- 2H-pyran-2-yl) oxy] methyl group undergoes a reaction that cuts off and binds to each other to form a macromolecule in a three-dimensional network, and some [(tetrahydro-2H-pyran-2- Yl) oxy] methyl group represents a structure that remains unreacted.
[(Tetrahydro-2H-pyran-2-yl) oxy] The reaction in which a part of the methyl group is cut and polymerized has not been elucidated, but a plurality of reactions as shown below compete in a single reaction. It is a reaction in which the compounds are linked to each other.

The reaction mode is shown below
Here, Ar represents an arbitrary aromatic ring of the charge transporting compound used in the present invention.
In this reaction, the tetrahydro-2H-pyran-2-yl moiety of one [(tetrahydro-2H-pyran-2-yl) oxy] methyl group is cut off and the other [(tetrahydro-2H-pyran-2-yl Yl) oxy] is a reaction in which the (tetrahydro-2H-pyran-2-yl) oxy group portion of the methyl group is cut to form a dimethylene ether bond.

Here, Ar represents an arbitrary aromatic ring of the charge transporting compound used in the present invention.
This reaction is a reaction in which the (tetrahydro-2H-pyran-2-yl) oxy group of both [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups is broken to form an ethylene bond.

Here, Ar represents an arbitrary aromatic ring of the charge transporting compound used in the present invention.
In this reaction, the (tetrahydro-2H-pyran-2-yl) oxy group of one [(tetrahydro-2H-pyran-2-yl) oxy] methyl group is cut off and bonded to the other aromatic ring. This reaction forms a methylene bond.
At least these reactions are combined to form a macromolecule by polymerizing in a three-dimensional network while taking a complicated bonding mode.

In general, (tetrahydro-2H-pyran-2-yl) oxy group is known as a hydroxyl-protecting group, but in the cured film of the present invention, [(tetrahydro-2H-pyran-2-yl) oxy] The methyl group remains and it is considered that the deprotection reaction has not occurred. That is, it shows that the [(tetrahydro-2H-pyran-2-yl) oxy] methyl group is not hydrolyzed and changed to a methylol group.
Furthermore, the (tetrahydro-2H-pyran-2-yl) oxy group has low polarity, and the remaining (tetrahydro-2H-pyran-2-yl) oxy group as an unreacted group has an adverse effect on electrical characteristics and image quality. Does not reach.

In addition, the polymerization reaction tends to form a highly strained film, but the relatively large [(tetrahydro-2H-pyran-2-yl) oxy] methyl group has an effect of reducing strain, An effect of filling a molecular space caused by strain can be expected, and a tough film with low gas permeability and reduced brittleness can be formed.
The reaction ratio and residual ratio of [(tetrahydro-2H-pyran-2-yl) oxy] methyl group in the molecule can be arbitrarily changed in order to adjust the structure of the charge transporting compound and the target film properties. However, if the residual amount is too small, it becomes a fragile film with a large strain, which is not suitable for a long-life photoreceptor. Moreover, in order to increase the reaction rate, it is necessary to raise the temperature, but problems such as a decrease in sensitivity and an increase in residual potential occur due to the influence of heat. Further, if the residual amount is excessively large, the crosslinking density is lowered, and in some cases, it is in a poorly cured state that dissolves in the organic solvent, and does not exhibit tough mechanical properties derived from the three-dimensional crosslinked film. Therefore, it is preferable to select a curing condition that satisfies both mechanical and electrostatic characteristics.

Next, a compound having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups in the aromatic ring of the charge transporting compound having an aromatic ring will be described.
Many materials have been known as charge transporting compounds. Most of these materials have aromatic rings. For example, an aromatic ring is present in any of the triarylamine structure, aminobiphenyl structure, benzidine structure, aminostilbene structure, naphthalenetetracarboxylic acid diimide structure, benzhydrazine structure, and the like. Any compound in which three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups are substituted on the aromatic ring of the charge transporting compound having an aromatic ring can be used.

In particular, the compound represented by the general formula (2) or (3) has the characteristics described above and can be preferably used. Among these, the compound represented by the general formula (3) is more preferable because it has a fast crosslinking reaction.
In the general formula (2), Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ and Ar ₆ in the formula are aromatic carbon atoms having 6 to 18 carbon atoms which may have an alkyl group as a substituent. Represents a divalent group of hydrogen. Here, examples of the aromatic hydrocarbon having 6 to 18 carbon atoms include benzene, naphthalene, fluorene, phenanthrene, anthracene, pyrene, and biphenyl. Examples of the alkyl group that may be substituted with these include linear or branched aliphatic alkyl groups such as methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, etc. Can be mentioned.
The aromatic hydrocarbon having 6 to 18 carbon atoms which may have an alkyl group as a substituent is preferably benzene, and the alkyl group which may be substituted is preferably a methyl group or an ethyl group.

In the general formula (2), X ₁ in the formula is an alkylene group having 1 to 4 carbon atoms, an alkylidene group having 2 to 6 carbon atoms, a cycloalkylidene group having 5 or 6 carbon atoms, or a phenylene group. It represents a divalent group in which two alkylidene groups having 2 to 6 carbon atoms are bonded, or an oxygen atom. Here, examples of the alkylene group having 1 to 4 carbon atoms include linear and branched alkylene groups such as a methylene group, an ethylene group, a propylene group, and a butylene group, and an alkylidene having 2 to 6 carbon atoms. As the group, 1,1-ethylidene group, 1,1-propylidene group, 2,2-propylidene group, 1,1-butylidene group, 2,2-butylidene group, 2,2-pentanilidene, 3,3-pentanilidene , 4-methyl-2,2-Pentaniriden, 3,3 Hekisaniriden like can be mentioned, as the cycloalkyl Li Den group 5 or 6 carbon atoms,
Can be mentioned. As the divalent group in which two alkylidene groups having 2 to 6 carbon atoms are bonded via a phenylene group, —C (CH ₃ ) ₂ —Ph—C (CH ₃ ) ₂ — is preferable. Is mentioned.
The _{X 1, -CH 2 -, -} CH 2 CH 2 -, - C (CH 3) 2 -Ph-C (CH 3) 2 -,
Or -O- is preferable.

The compound represented by the general formula (2) will be described below with specific examples, but the present invention is not limited to these exemplified compounds.

The above compound having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring of the charge transporting compound is a novel compound and can be produced, for example, by the following method.
The first method is to formylate the aromatic ring of the charge transporting compound at three or more sites, then reduce the formyl group to methylolate, and then react 3,4-dihydro-2H-pyran with the methylol group [( It is a method of attaching a tetrahydro-2H-pyran-2-yl) oxy] methyl group to a charge transporting compound.
For example, an aldehyde compound is synthesized by the following procedure, a methylol compound is synthesized by reacting the obtained aldehyde compound with a reducing agent such as sodium borohydride, and the resulting methylol compound is reacted with dihydro-2H-pyran. Thus, a compound having [(tetrahydro-2H-pyran-2-yl) oxy] methyl group on the aromatic ring of the charge transporting compound can be obtained. Specifically, it can be easily synthesized by the following production method.

In the second method, a compound having a halogen and a methylol group in an aromatic ring is used as a raw material, and the methylol group is reacted with 3,4-dihydro-2H-pyran in the presence of an acid catalyst to produce halogen and [(tetrahydro-2H -Pyran-2-yl) oxy] This is a method of synthesizing an aromatic compound having a methyl group and using this to carry out a coupling reaction with an amine compound to synthesize a charge transporting compound.
Depending on the series and number of amines, a large number of [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups can be introduced at once. When halogen is an iodo compound, an amine compound and a halogen compound having a [(tetrahydro-2H-pyran-2-yl) oxy] methyl group can be coupled by an Ullmann reaction. In the case of a chloro form or a bromo form, it can be coupled by a Suzuki-Miyaura reaction using a palladium catalyst.

<Synthesis of aldehyde compound>
As shown in the following reaction formula, a charge transporting compound is used as a raw material, and this is formylated by using a conventionally known method (for example, Vilsmeier reaction) to synthesize an aldehyde compound. Examples include formylation described in Japanese Patent No. 3934522.
That is, as a specific formylation method, a method using zinc chloride / phosphorus oxychloride / dimethylformaldehyde is effective, but a synthesis method for obtaining an aldehyde compound as an intermediate of the present invention is as follows. It is not limited to these. A specific synthesis example will be described later in the synthesis example.

<Synthesis of methylol compound>
As shown in the following reaction formula, an aldehyde compound is used as a production intermediate, and a methylol compound can be synthesized by using a conventionally known reduction method.
That is, as the specific reduction method described above, a method using sodium borohydride is effective, but the synthesis method for obtaining the methylol compound of the present invention is not limited thereto. Specific synthesis examples will be described in the examples described later.

<Synthesis of Compound Having [(Tetrahydro-2H-pyran-2-yl) oxy] methyl Group on the Aromatic Ring of Charge Transporting Compound [1]>
As shown in the following reaction formula, a methylol compound is used as a production intermediate, and 3,4-dihydro-2H-pyran is subjected to addition reaction in the presence of a catalyst to form an aromatic ring of the charge transporting compound (tetrahydro-2H-pyran). A compound having a -2-yl) oxy] methyl group can be synthesized.
That is, as a specific synthetic method, a method using dihydro-2H-pyran is effective, but [(tetrahydro-2H-pyran-2-yl) is added to the aromatic ring of the charge transporting compound of the present invention. The synthesis method for obtaining a compound having an oxy] methyl group is not limited thereto. Specific synthesis examples will be described in the examples described later.

<Synthesis of Intermediate Compound Having [(Tetrahydro-2H-pyran-2-yl) oxy] methyl Group>
In the formula, X represents halogen.

<Synthesis of Compound Having [(Tetrahydro-2H-pyran-2-yl) oxy] methyl Group on the Aromatic Ring of Charge Transporting Compound [2]>
As shown in the following reaction formula, an amine compound and a halogen compound having a tetrahydropyranyl group are used as intermediates for production, and this is added to the aromatic ring of the charge transporting compound [(tetrahydro-2H- A compound having a pyran-2-yl) oxy] methyl group can be synthesized.
That is, as a specific synthesis method described above, a method using the Ullmann reaction or the like is effective, but a [(tetrahydro-2H-pyran-2-yl) oxy] methyl group is added to the aromatic ring of the charge transporting compound. The synthesis method for obtaining the compound having the above is not limited to these. A specific synthesis example will be described later in the synthesis example.

Next, the sulfonic acid amine salt will be described.
The sulfonic acid amine salt in the present invention can be easily obtained by reacting a sulfonic acid and an amine at room temperature. Among the sulfonic acid amine salts, those having a pH of 4 or more and 7 or less when a 0.01 mol / l aqueous solution is prepared are preferred for the reasons described above.
The pH of the sulfonic acid amine salt aqueous solution can be measured with a glass electrode pH meter HM-30 manufactured by Toa Denpa Kogyo Co., Ltd. after the sulfonic acid amine salt is dissolved in ion-exchanged water and uniformly mixed.

The sulfonic acid amine salt is 0.3 to 4.0% by mass in solid content of the sulfonic acid amine salt based on the compound having [(tetrahydro-2H-pyran-2-yl) oxy] methyl group in the aromatic ring. It is preferable to add a certain amount. If the amount added is too large, the crosslink density increases too much, causing a decrease in charge transportability, and the light portion potential of the photoreceptor tends to increase or the sensitivity tends to decrease.
The sulfonic acid used for the synthesis of the sulfonic acid amine salt is preferably paratoluenesulfonic acid or vinylsulfonic acid.
Paratoluenesulfonic acid or vinylsulfonic acid has a high catalytic activity when dissociated from the sulfonic acid amine salt, and can form a three-dimensional crosslinked film having a high crosslinking density. Moreover, since it does not have a bulky substituent, it is easily neutralized by an amine, and is excellent in the stability of coating solution and the effect of suppressing a decrease in image density.

As the amine used for the synthesis of the sulfonic acid amine salt, any amine can be used as long as the pH in the 0.01 mol / l aqueous solution when the sulfonic acid amine salt is 4 or more and 7 or less. However, an amine of the following general formula (1) is more preferably used.
(In the formula, R ₁ and R ₂ may be the same or different and each represents hydrogen or an alkyl group having 1 to 5 carbon atoms. R ₃ represents an alkyl group having 1 to 5 carbon atoms which may have a hydroxyl group. Show.)

  In the amine of the general formula (1), since a sterically bulky substituent such as a phenyl group or a naphthyl group is not directly bonded to a nitrogen atom, it is easy to form a salt with paratoluenesulfonic acid, and the coating solution is stable. And an excellent effect of suppressing a decrease in image density.

Specific compounds of the amine of the general formula (1) are shown below, but the present invention is not limited to these compounds.
For example, examples of the primary amine include isopropylamine, pentylamine, tert-butylamine, ethanolamine, 1-amino-2-propanol, 3-amino-1-propanol and the like. Secondary amines include diethylamine, N-ethylpropylamine, di-n-butylamine, N-sec-butylpropylamine, 2- (methylamino) ethanol, 2- (isopropylamino) ethanol, 3-methylamino-1- Examples include propanol, 1-methylamino-2-propanol, 4-aminoethyl-1-butanol. Tertiary amines include N-butyldimethylamine, triethylamine, tripropylamine, 1-dimethylamino-2-propanol, 2- (dimethylamino) ethanol, 4-dimethylamino-1-butanol, 2- (dibutylamino) Examples include ethanol.
A specific synthesis example will be described later in the synthesis example.

Next, the method for forming the three-dimensional crosslinked film will be described in detail.
The three-dimensional crosslinked membrane requires a coating solution containing a compound having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring of the charge transporting compound and a sulfonic acid amine salt. In accordance with the above, after dilution adjustment with a solvent or the like, the coating solution is applied to the surface of the photoreceptor, and then dried by heating and polymerized. Alternatively, two or more charge transporting compounds having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups bonded to an aromatic ring may be mixed and formed in the same manner.

The heating temperature is preferably in the range of 80 ° C to 180 ° C, and more preferably in the range of 100 ° C to 160 ° C. Since the reaction rate varies depending on the type and addition amount of the catalyst, it may be arbitrarily selected depending on the formulation conditions. The higher the heating temperature is, the faster the reaction is. However, if the crosslinking density is too high, the charge transportability is lowered and the light portion potential of the photoreceptor is raised or the sensitivity is lowered. Further, the influence of heating on the other layer constituting materials of the photoconductor is increased, and the photoconductor characteristics are easily deteriorated there. If the heating temperature is too low, the reaction rate becomes slow, and there is a problem that a sufficient crosslinking density cannot be reached over a long period of time.
The heating time for forming the three-dimensional crosslinked film is preferably 20 minutes to 60 minutes when heated at 135 ° C. to 150 ° C.

In the case where the three-dimensional crosslinked film of the present invention is used as a crosslinked charge transport layer, an example of the coating method is as follows: [(tetrahydro-2H-pyran-2-yl) oxy] on the aromatic ring of the charge transport compound About 0.3 to 4.0% by mass of a sulfonic acid amine salt is added to a compound having 3 or more methyl groups, and a solvent is further added to prepare a coating solution. For example, in the charge transport layer that is the lower layer of the crosslinkable charge transport layer, when using a triarylamine-based donor as the charge transport material and polycarbonate as the binder resin, spraying the crosslinkable charge transport layer thereon, As the solvent for the coating solution, tetrahydrofuran, 2-butanone, ethyl acetate and the like are preferable. The amount of the solvent used is about 3 to 10 times the amount of the compound having 3 or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups in the aromatic ring of the charge transporting compound.
Next, for example, the prepared coating solution is applied by spraying or the like on a photoreceptor in which an undercoat layer, a charge generation layer, and the charge transport layer are sequentially laminated on a support such as an aluminum cylinder. Thereafter, the crosslinked charge transport layer is formed by heating.
The heating temperature is preferably in the range of 80 to 180 ° C. For example, when heated at 135 ° C to 150 ° C, the heating temperature is preferably 20 minutes to 60 minutes.

  As described above, the three-dimensional crosslinked film of the present invention having various crosslinking densities can be formed by arbitrarily selecting the heating and drying temperature and time while taking into consideration the type and addition amount of the catalyst.

  Examples of the solvent include alcohols such as methanol, ethanol, propanol and butanol, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, esters such as ethyl acetate and butyl acetate, tetrahydrofuran, methyltetrahydrofuran, dioxane, Propyl ether, diethylene glycol dimethyl ether, propylene glycol 1-monomethyl ether 2-acetate ethers, dichloromethane, dichloroethane, trichloroethane, chlorobenzene and other halogens, benzene, toluene, xylene and other aromatics, methyl cellosolve, ethyl cellosolve, cellosolve Examples include cellosolve such as acetate. These solvents may be used alone or in combination of two or more. The dilution ratio with the solvent varies depending on the solubility of the composition, the coating method, and the desired thickness, and is arbitrary. The application can be performed by dip coating, spray coating, bead coating, ring coating, or the like.

  Furthermore, the coating solution may contain additives such as a leveling agent and an antioxidant as necessary. As leveling agents, silicone oils such as dimethyl silicone oil and methylphenyl silicone oil, and polymers and oligomers having a perfluoroalkyl group in the side chain are used, and the amount used is 1% by mass or less based on the total solid amount. Is preferred. Moreover, antioxidant can also be used effectively. For example, conventionally known materials such as phenolic compounds, paraphenylenediamines, hydroquinones, organic sulfur compounds, organic phosphorus compounds, hindered amines and the like can be used, which is effective for stabilizing electrostatic characteristics against repeated use. As addition amount, 1 mass% or less is preferable with respect to the total solid amount.

  Furthermore, a filler can be added to the coating solution for the purpose of further improving the wear resistance. The filler includes an organic filler material and an inorganic filler material. Examples of the organic filler material include fluororesin powder such as polytetrafluoroethylene, silicone resin powder, a-carbon powder, etc., and inorganic filler material includes metal powder such as copper, tin, aluminum, indium, Metal oxides such as silica, tin oxide, zinc oxide, titanium oxide, alumina, zirconium oxide, indium oxide, antimony oxide, bismuth oxide, calcium oxide, antimony-doped tin oxide, tin-doped indium oxide, tin fluoride Metal fluorides such as calcium fluoride and aluminum fluoride, and inorganic materials such as potassium titanate and boron nitride. Among these fillers, it is advantageous to use an inorganic material from the viewpoint of the hardness of the filler to improve the wear resistance. Among these fillers, α-type alumina having a hexagonal close-packed structure having high insulation, high thermal stability and high wear resistance is particularly useful from the viewpoint of improvement in wear resistance.

  Furthermore, these fillers can be surface-treated with at least one kind of surface treatment agent, which is preferable because the dispersibility of the filler is improved. Decreasing the dispersibility of the filler not only increases the residual potential, but also decreases the transparency of the coating, causes defects in the coating, and decreases the wear resistance. It can develop into a big problem.

As the surface treatment agent, all conventionally used surface treatment agents can be used, but a surface treatment agent capable of maintaining the insulating properties of the filler is preferable. For example, titanate coupling agents, aluminum coupling agents, zircoaluminate coupling agents, higher fatty acids, etc., or mixed treatments thereof with silane coupling agents, Al ₂ O ₃ , TiO ₂ , ZrO ₂ , Silicone, aluminum stearate, or the like, or a mixture thereof is more preferable from the viewpoint of filler dispersibility and image blur. The treatment with the silane coupling agent is strongly influenced by image blur, but the influence may be suppressed by performing a mixing treatment of the surface treatment agent and the silane coupling agent.

  The amount of the surface treatment agent varies depending on the average primary particle size of the filler used, but is preferably 3 to 30 wt%, more preferably 5 to 20 wt%. If the amount of the surface treatment agent is less than this, the filler dispersing effect cannot be obtained, and if it is too much, the residual potential is significantly increased. The average primary particle size of the filler is preferably 0.01 to 0.5 μm from the viewpoint of light transmittance and wear resistance. When the average primary particle size of the filler is less than 0.01 μm, it causes a decrease in wear resistance, a decrease in dispersibility, etc., and when it exceeds 0.5 μm, the settling of the filler is promoted or the toner fills. May occur.

  Moreover, as content of a filler, 0-50 wt% is preferable, More preferably, it is 10-40 wt%. The wear resistance is improved by containing a filler, but if it exceeds 50 wt%, the transparency is impaired.

Next, the layer structure of the electrophotographic photosensitive member of the present invention will be described with reference to FIGS. 25 to 29 are cross-sectional views of the electrophotographic photosensitive member.
FIG. 25 is a configuration example of the most basic laminated photoconductor, in which a charge generation layer (2) and a charge transport layer (3) are sequentially laminated on a conductive support (1). When used in a negative charge, a hole transporting charge transport material is used for the charge transport layer, and when used in a positive charge, an electron transporting charge transport material is used for the charge transport layer.
In these cases, the outermost surface layer is the charge transport layer (3), and therefore the charge transport compound having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups in the aromatic ring of the present invention. The three-dimensional crosslinked film formed by the condensation reaction is applied to this charge transport layer.

  FIG. 26 shows a configuration in which an undercoat layer (4) is formed on a laminated photoconductor having a basic configuration, which is the most practical configuration. Also in this case, the outermost surface layer is the charge transport layer (3). Therefore, the charge transport compound having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups in the aromatic ring of the present invention. The three-dimensional crosslinked film formed by the condensation reaction is applied to this charge transport layer.

FIG. 27 shows a configuration in which a cross-linkable charge transport layer (5) is further provided on the outermost surface. Therefore, three [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups are present in the aromatic ring of the present invention. The three-dimensional crosslinked film formed by the condensation reaction of the charge transporting compound having the above is applied to this crosslinked charge transport layer.
Here, the undercoat layer is not essential, but it plays an important function for preventing charge leakage and is usually used.
In the case of this photoconductor structure, the charge transfer from the charge generation layer to the surface of the photoconductor is shared by the charge transport layer (3) and the cross-linked charge transport layer (5), and the main function can be separated. it can. For example, by combining a charge transport layer having excellent charge transportability and a cross-linked charge transport layer having excellent mechanical strength, it is possible to provide a photoreceptor having excellent charge transportability and excellent mechanical strength.

  The three-dimensional crosslinked film formed by the condensation reaction of a charge transporting compound having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring of the present invention is charged in the crosslinked film. Although it is a film having excellent transportability and high applicability as a charge transport layer (3), the charge transportability is inferior to that of a conventional molecular dispersion type charge transport layer. Accordingly, it is preferable to use a relatively thin film, and when used in such a configuration, a photoreceptor having the most excellent characteristics can be provided.

  In FIG. 28, a photosensitive layer (6) mainly composed of a charge generation material and a charge transport material is provided on a conductive support (1). The photosensitive layer (6) uses a three-dimensional crosslinked film formed by a condensation reaction of a charge transporting compound having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring of the present invention. can do. In this case, it is necessary to contain a charge generating substance in the crosslinked film, and a coating liquid in which the charge generating substance is mixed and dispersed in the coating liquid is prepared, and after coating, it is condensed by heating and drying. Reaction is performed to produce a three-dimensional crosslinked film.

  FIG. 29 shows a structure in which a protective layer (7) is provided on the surface of a single-layer photosensitive layer (6). The protective layer (7) has an aromatic ring [(tetrahydro-2H-pyran-2-yl )] A three-dimensional crosslinked film formed by a condensation reaction of a charge transporting compound having 3 or more oxymethyl groups is used.

As the constituent elements of these layers, conventionally known ones can be used in all places where the three-dimensional crosslinked film of the present invention is not applied.
Hereinafter, other components will be described in detail.

<Conductive support>
The conductive support is not particularly limited as long as it has a volume resistance of 10 ¹⁰ Ω · cm or less, and can be appropriately selected according to the purpose. For example, aluminum, nickel, chromium, nichrome Metals such as copper, gold, silver, and platinum; metal oxides such as tin oxide and indium oxide by vapor deposition or sputtering, film or cylindrical plastic, paper coated, or aluminum, aluminum alloy, nickel, It is possible to use a plate made of stainless steel or the like and a tube subjected to surface treatment such as cutting, super-finishing, polishing, etc. after forming the raw tube by a method such as extruding and drawing. Further, an endless nickel belt and an endless stainless steel belt disclosed in Japanese Patent Publication No. 52-36016 can be used as the conductive support.

In addition, what provided the electroconductive layer which disperse | distributed electroconductive powder to the appropriate binder resin on the said electroconductive support body, and provided may be used as the electroconductive support body of this invention.
Examples of the conductive powder include carbon black, acetylene black, metal powder such as aluminum, nickel, iron, nichrome, copper, zinc and silver, or metal oxide powder such as conductive tin oxide and ITO. Etc. The binder resin used at the same time includes polystyrene resin, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester resin, polyvinyl chloride resin, vinyl chloride-vinyl acetate. Copolymer, polyvinyl acetate resin, polyvinylidene chloride resin, polyarylate resin, phenoxy resin, polycarbonate resin, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral resin, polyvinyl formal resin, polyvinyl toluene resin, poly-N-vinyl carbazole, Thermoplastic, thermosetting resin, or photocurable resin such as acrylic resin, silicone resin, epoxy resin, melamine resin, urethane resin, phenol resin, alkyd resin, and the like can be given.

The conductive layer can be provided by dispersing and applying these conductive powder and binder resin in a suitable solvent such as tetrahydrofuran, dichloromethane, methyl ethyl ketone, toluene and the like.
Furthermore, it is electrically conductive by a heat shrinkable tube in which the conductive powder is contained in a material such as polyvinyl chloride, polypropylene, polyester, polystyrene, polyvinylidene chloride, polyethylene, chlorinated rubber, Teflon (registered trademark) on a suitable cylindrical substrate. Those provided with a conductive layer can also be used favorably as the support of the present invention.

<Underlayer>
In the electrophotographic photoreceptor of the present invention, an undercoat layer can be provided between the support and the photosensitive layer. The undercoat layer generally comprises a resin as a main component. However, considering that the photosensitive layer is applied with a solvent thereon, these resins are resins having a high solvent resistance with respect to general organic solvents. Is desirable. Examples of the resin include water-soluble resins such as polyvinyl alcohol, casein, and sodium polyacrylate, alcohol-soluble resins such as copolymer nylon and methoxymethylated nylon, polyurethane, melamine resin, phenol resin, alkyd-melamine resin, and epoxy. Examples thereof include a curable resin that forms a three-dimensional network structure such as a resin. In order to prevent moire and reduce residual potential, the undercoat layer is added with a fine powder pigment of a metal oxide such as titanium oxide, silica, alumina, zirconium oxide, tin oxide, or indium oxide. be able to.

In the undercoat layer, a material in which Al ₂ O ₃ is provided by anodic oxidation, an organic material such as polyparaxylylene (parylene), or an inorganic material such as SiO ₂ , SnO ₂ , TiO ₂ , ITO, CeO ₂ is vacuumed. Those provided by the thin film manufacturing method can also be used favorably. In addition, known ones can be used.
The undercoat layer can be formed using an appropriate solvent and a coating method like the above-described photosensitive layer. Furthermore, a silane coupling agent, a titanium coupling agent, a chromium coupling agent, or the like can be used as the undercoat layer of the present invention. There is no restriction | limiting in particular in the thickness of the said undercoat layer, According to the objective, it can select suitably, 1-5 micrometers is preferable.
The undercoat layer may be a laminate of two or more layers in combination of the above types.

<Charge generation layer>
The charge generation layer contains at least a charge generation material, and further contains a binder resin and, if necessary, other components. As the charge generation material, inorganic materials and organic materials can be used.
Examples of the inorganic material include crystalline selenium, amorphous-selenium, selenium-tellurium, selenium-tellurium-halogen, selenium-arsenic compound, and amorphous-silicon. In amorphous-silicon, dangling bonds that are terminated with hydrogen atoms or halogen atoms, or those that are doped with boron atoms or phosphorus atoms are preferably used.

  The organic material is not particularly limited and may be appropriately selected from known materials according to the purpose. For example, phthalocyanine pigments such as metal phthalocyanine and metal-free phthalocyanine, azurenium salt pigments, squaric acid methine Pigment, azo pigment having carbazole skeleton, azo pigment having triphenylamine skeleton, azo pigment having diphenylamine skeleton, azo pigment having dibenzothiophene skeleton, azo pigment having fluorenone skeleton, azo pigment having oxadiazole skeleton, bis Azo pigments having a stilbene skeleton, azo pigments having a distyryl oxadiazole skeleton, azo pigments having a distyryl carbazole skeleton, perylene pigments, anthraquinone or polycyclic quinone pigments, quinoneimine pigments, diphenylmethane and triphenyl Enirumetan pigments, benzoquinone and naphthoquinone pigments, cyanine and azomethine pigments, indigoid pigments, and bisbenzimidazole pigments. These may be used individually by 1 type and may use 2 or more types together.

  There is no restriction | limiting in particular as said binder resin, According to the objective, it can select suitably, For example, a polyamide resin, a polyurethane resin, an epoxy resin, a polyketone resin, a polycarbonate resin, a silicone resin, an acrylic resin, a polyvinyl butyral resin, polyvinyl Formal resins, polyvinyl ketone resins, polystyrene resins, poly-N-vinyl carbazole resins, polyacrylamide resins and the like can be mentioned. These may be used individually by 1 type and may use 2 or more types together.

  In addition to the binder resin described above, the charge generation layer binder resin may be a polymer charge transport material having a charge transport function, such as (1) an arylamine skeleton, a benzidine skeleton, a hydrazone skeleton, a carbazole skeleton, or a stilbene skeleton. Or a polymer material such as polycarbonate, polyester, polyurethane, polyether, polysiloxane, or acrylic resin having a pyrazoline skeleton, or (2) a polymer material having a polysilane skeleton.

Specific examples of the above (1) include JP-A-01-001728, JP-A-01-009964, JP-A-09-302084, JP-A-09-302085, JP-A-09-328539. Examples thereof include charge transporting polymer materials described in publications.
Specific examples of the above (2) include, for example, those described in JP-A-63-285552, JP-A-05-19497, JP-A-05-70595, JP-A-10-73944, and the like. Examples are polysilylene polymers.

The charge generation layer may contain a low molecular charge transport material. The low molecular charge transport material includes a hole transport material and an electron transport material.
Examples of the electron transporting material include chloroanil, bromoanil, tetracyanoethylene, tetracyanoquinodimethane, 2,4,7-trinitro-9-fluorenone, 2,4,5,7-tetranitro-9-fluorenone, 2 , 4,5,7-tetranitroxanthone, 2,4,8-trinitrothioxanthone, 2,6,8-trinitro-4H-indeno [1,2-b] thiophen-4-one, 1,3,7 -Trinitrodibenzothiophene-5,5-dioxide, diphenoquinone derivatives and the like. These may be used individually by 1 type and may use 2 or more types together.

  Examples of the hole transport material include oxazole derivatives, oxadiazole derivatives, imidazole derivatives, monoarylamine derivatives, diarylamine derivatives, triarylamine derivatives, stilbene derivatives, α-phenylstilbene derivatives, benzidine derivatives, diarylmethane derivatives. , Triarylmethane derivatives, 9-styrylanthracene derivatives, pyrazoline derivatives, divinylbenzene derivatives, hydrazone derivatives, indene derivatives, butadiene derivatives, pyrene derivatives, and the like, and other known materials such as bisstilbene derivatives and enamine derivatives. These may be used individually by 1 type and may use 2 or more types together.

As a method for forming the charge generation layer, a vacuum thin film preparation method and a casting method from a solution dispersion system can be mentioned.
As the vacuum thin film production method, for example, a vacuum deposition method, a glow discharge decomposition method, an ion plating method, a sputtering method, a reactive sputtering method, a CVD method, or the like is used.
As the casting method, the inorganic or organic charge generating material, and optionally binder resin, tetrahydrofuran, dioxane, dioxolane, toluene, dichloromethane, monochlorobenzene, dichloroethane, cyclohexanone, cyclopentanone, anisole, xylene, methyl ethyl ketone It can be formed by dispersing with a ball mill, attritor, sand mill, bead mill or the like using a solvent such as acetone, ethyl acetate, butyl acetate, etc., and applying the solution after diluting the dispersion appropriately. Moreover, leveling agents, such as a dimethyl silicone oil and a methylphenyl silicone oil, can be added as needed. The application can be performed by dip coating, spray coating, bead coating, ring coating, or the like.

  The thickness of the charge generation layer is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 0.01 to 5 μm, and more preferably 0.05 to 2 μm.

<Charge transport layer>
The charge transport layer is a layer intended to hold a charged charge and to couple the charge generated and separated in the charge generation layer by exposure to the charged charge held by movement. In order to achieve the purpose of holding the charged charge, it is required that the electric resistance is high. Further, in order to achieve the purpose of obtaining a high surface potential with the charged charge that has been held, it is required that the dielectric constant is small and the charge mobility is good.

The charge transport layer includes at least a charge transport material, and includes a binder resin and, if necessary, other components.
Examples of the charge transport material include a hole transport material, an electron transport material, and a polymer charge transport material.

  Examples of the electron transporting material (electron accepting material) include chloranil, bromanyl, tetracyanoethylene, tetracyanoquinodimethane, 2,4,7-trinitro-9-fluorenone, 2,4,5,7-tetranitro. -9-fluorenone, 2,4,5,7-tetranitroxanthone, 2,4,8-trinitrothioxanthone, 2,6,8-trinitro-4H-indeno [1,2-b] thiophene-4-one, 1,3,7-trinitrodibenzothiophene-5,5-dioxide, and the like. These may be used individually by 1 type and may use 2 or more types together.

  Examples of the hole transport material (electron donating material) include oxazole derivatives, oxadiazole derivatives, imidazole derivatives, triphenylamine derivatives, 9- (p-diethylaminostyrylanthracene), 1,1-bis- (4 -Dibenzylaminophenyl) propane, styrylanthracene, styrylpyrazoline, phenylhydrazones, α-phenylstilbene derivatives, thiazole derivatives, triazole derivatives, phenazine derivatives, acridine derivatives, benzofuran derivatives, benzimidazole derivatives, thiophene derivatives, etc. . These may be used individually by 1 type and may use 2 or more types together.

Examples of the polymer charge transport material include those having the following structure.
Examples of (a) a polymer having a carbazole ring include, for example, poly-N-vinylcarbazole, JP-A-50-82056, JP-A-54-9632, JP-A-54-11737, JP-A-5-11737. Examples thereof include compounds described in JP-A-4-175337, JP-A-4-183719, and JP-A-6-234841.
(B) Examples of the polymer having a hydrazone structure include, for example, JP-A-57-78402, JP-A-61-20953, JP-A-61-296358, JP-A-1-134456, Compounds described in Kaihei 1-179164, JP-A-3-180851, JP-A-3-180852, JP-A-3-50555, JP-A-5-310904, and JP-A-6-234840 Etc. are exemplified.
(C) Examples of the polysilylene polymer include, for example, JP-A-63-285552, JP-A-1-88461, JP-A-4-264130, JP-A-4-264131, and JP-A-4-264132. Examples thereof include compounds described in JP-A-4-264133 and JP-A-4-289867.
(D) As a polymer having a triarylamine structure, for example, N, N-bis (4-methylphenyl) -4-aminopolystyrene, JP-A-1-134457, JP-A-2-282264, Examples thereof include compounds described in Kaihei 2-304456, JP-A-4-133605, JP-A-4-133066, JP-A-5-40350, and JP-A-5-202135.
(E) As other polymers, for example, a formaldehyde condensation polymer of nitropyrene, JP-A-51-73888, JP-A-56-15049, JP-A-6-234363, JP-A-6-234837 And the compounds described in Japanese Patent Publication No.

  In addition to the above, the polymer charge transporting material includes, for example, a polycarbonate resin having a triarylamine structure, a polyurethane resin having a triarylamine structure, a polyester resin having a triarylamine structure, and a triarylamine structure. And a polyether resin. Examples of the polymer charge transporting material include JP-A 64-1728, JP-A 64-13061, JP-A 64-19049, JP-A-4-11627, JP-A 4-116627. JP 2225014, JP 4-230767, JP 4-320420, JP 5-232727, JP 7-56374, JP 9-127713, JP 9-222740. And compounds described in JP-A-9-265197, JP-A-9-211877, JP-A-9-30495, and the like.

Examples of the polymer having an electron donating group include not only the above-mentioned polymer but also a copolymer with a known monomer, a block polymer, a graft polymer, a star polymer, It is also possible to use a crosslinked polymer having an electron donating group as disclosed in JP-A-109406.
Examples of the binder resin include polycarbonate resin, polyester resin, methacrylic resin, acrylic resin, polyethylene resin, polyvinyl chloride resin, polyvinyl acetate resin, polystyrene resin, phenol resin, epoxy resin, polyurethane resin, polyvinylidene chloride resin, Alkyd resins, silicone resins, polyvinyl carbazole resins, polyvinyl butyral resins, polyvinyl formal resins, polyacrylate resins, polyacrylamide resins, phenoxy resins, and the like are used. These may be used individually by 1 type and may use 2 or more types together.

The charge transport layer may also contain a copolymer of a crosslinkable binder resin and a crosslinkable charge transport material.
The charge transport layer can be formed by dissolving or dispersing these charge transport materials and a binder resin in an appropriate solvent, and applying and drying them. In addition to the charge transport material and the binder resin, an appropriate amount of additives such as a plasticizer, an antioxidant, and a leveling agent may be added to the charge transport layer as necessary.

As the solvent used for coating the charge transport layer, the same solvent as the charge generation layer can be used, but a solvent that dissolves the charge transport material and the binder resin well is suitable. These solvents may be used alone or in combination of two or more. The charge transport layer can be formed by the same coating method. If necessary, a plasticizer and a leveling agent can be added.
As said plasticizer, what is used as a plasticizer of general resins, such as dibutyl phthalate and a dioctyl phthalate, can be used as it is, and the usage-amount is 0-30 mass with respect to 100 mass parts of said binder resins. Part is appropriate.
Examples of the leveling agent include silicone oils such as dimethyl silicone oil and methylphenyl silicone oil, and polymers or oligomers having a perfluoroalkyl group in the side chain. The amount used is 100 parts by mass of a binder resin. About 0 to 1 part by mass is appropriate.

  There is no restriction | limiting in particular in the thickness of the said charge transport layer, According to the objective, it can select suitably, 5-40 micrometers is preferable and 10-30 micrometers is more preferable.

In the electrophotographic photoreceptor of the present invention, an intermediate is provided between the charge transport layer and the cross-linked charge transport layer for the purpose of suppressing mixing of the charge transport layer component into the cross-linked charge transport layer or improving adhesion between the two layers. It is possible to provide a layer.
For this reason, as the intermediate layer, those that are insoluble or hardly soluble in the crosslinking type charge transport layer coating solution are suitable, and generally a binder resin is used as a main component. Examples of these resins include polyamide, alcohol-soluble nylon, water-soluble polyvinyl butyral, polyvinyl butyral, and polyvinyl alcohol. As the method for forming the intermediate layer, the coating method is employed. The thickness of the intermediate layer is not particularly limited and can be appropriately selected depending on the purpose, and is preferably 0.05 to 2 μm.

<Single layer photosensitive layer>
The single-layer photosensitive layer comprises at least a charge generation material, a charge transport material, a binder resin, and, if necessary, other components. It can be formed by dissolving or dispersing this in a suitable solvent, coating and drying. As the charge generation material and the charge transport material, the same materials as those already described in the charge generation layer and the charge transport layer can be used. As the binder resin, in addition to the binder resin mentioned above in the section of the charge transport layer, the binder resin mentioned in the charge generation layer may be mixed and used. As a dispersion method, the same method as already described in the charge generation layer can be used.
The thickness of such a single photosensitive layer is suitably about 5 to 30 μm, preferably 10 to 25 μm.

<Addition of antioxidant to each layer>
In the electrophotographic photosensitive member of the present invention, in order to improve environmental resistance, in particular, for the purpose of preventing a decrease in sensitivity and an increase in residual potential, the cross-linked charge transport layer, the charge transport layer, the charge generation layer, An antioxidant may be added to each layer such as the undercoat layer and the intermediate layer.

Examples of the antioxidant include phenolic compounds, paraphenylenediamines, hydroquinones, organic sulfur compounds, and organic phosphorus compounds. These may be used individually by 1 type and may use 2 or more types together.
Examples of the phenol compound include 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl-4-ethylphenol, stearyl-β- (3, 5-di-t-butyl-4-hydroxyphenyl) propionate, 2,2'-methylene-bis- (4-methyl-6-t-butylphenol), 2,2'-methylene-bis- (4-ethyl- 6-t-butylphenol), 4,4′-thiobis- (3-methyl-6-tert-butylphenol), 4,4′-butylidenebis- (3-methyl-6-tert-butylphenol), 1,1,3 -Tris- (2-methyl-4-hydroxy-5-t-butylphenyl) butane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxy Ben ) Benzene, tetrakis- [methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] methane, bis [3,3′-bis (4′-hydroxy-3 ′) -T-butylphenyl) butyric acid] cricol ester, tocopherols, and the like.

  Examples of the paraphenylenediamines include N-phenyl-N′-isopropyl-p-phenylenediamine, N, N′-di-sec-butyl-p-phenylenediamine, N-phenyl-N-sec-butyl- p-phenylenediamine, N, N′-di-isopropyl-p-phenylenediamine, N, N′-dimethyl-N, N′-di-t-butyl-p-phenylenediamine, and the like.

  Examples of the hydroquinones include 2,5-di-t-octyl hydroquinone, 2,6-didodecyl hydroquinone, 2-dodecyl hydroquinone, 2-dodecyl-5-chlorohydroquinone, 2-t-octyl-5-methyl. And hydroquinone and 2- (2-octadecenyl) -5-methylhydroquinone.

Examples of the organic sulfur compounds include dilauryl-3,3′-thiodipropionate, distearyl-3,3′-thiodipropionate, ditetradecyl-3,3′-thiodipropionate, and the like. It is done.
Examples of the organic phosphorus compounds include triphenylphosphine, tri (nonylphenyl) phosphine, tri (dinonylphenyl) phosphine, tricresylphosphine, tri (2,4-dibutylphenoxy) phosphine, and the like.
In addition, these compounds are known as antioxidants, such as rubber | gum, a plastic, and fats and oils, and a commercial item can be obtained easily.

  There is no restriction | limiting in particular in the addition amount of the said antioxidant, According to the objective, it can select suitably, 0.01-10 mass% is preferable with respect to the total mass of the layer to add.

<Image Forming Method and Apparatus>
Next, the image forming method and the image forming apparatus of the present invention will be described in detail with reference to the drawings.
FIG. 30 is a schematic diagram for explaining the electrophotographic process and the image forming apparatus of the present invention, and the following examples also belong to the category of the present invention.

  The photoconductor (10) rotates in the direction of the arrow in FIG. 30. Around the photoconductor (10), a charging member (11), an image exposure member (12), a developing member (13), and a transfer member (16). ), A cleaning member (17), a charge removal member (18), and the like are disposed. The cleaning member (17) and the charge removal member (18) may be omitted.

  The operation of the image forming apparatus is basically as follows. The charging member (11) charges the surface of the photoreceptor (10) almost uniformly. Subsequently, image light writing corresponding to the input signal is performed by the image exposure member (12) to form an electrostatic latent image. Next, the electrostatic latent image is developed by the developing member (13), and a toner image is formed on the surface of the photoreceptor. The formed toner image is transferred onto the transfer paper (15) sent to the transfer site by the transport roller (14) by the transfer member. This toner image is fixed on the transfer paper by a fixing device (not shown). Part of the toner that has not been transferred to the transfer paper is cleaned by the cleaning member (17). Next, the charge remaining on the photoreceptor is neutralized by the neutralizing member (18), and the process proceeds to the next cycle.

  As shown in FIG. 30, the photoconductor (10) has a drum shape, but may have a sheet shape or an endless belt shape. As the charging member (11) and the transfer member (16), in addition to corotron, scorotron, solid state charger (solid state charger), a roller-shaped charging member or a brush-shaped charging member is used. Are all usable.

On the other hand, light sources such as the image exposure member (12) and the charge removal member (18) include fluorescent lamps, tungsten lamps, halogen lamps, mercury lamps, sodium lamps, light emitting diodes (LEDs), semiconductor lasers (LD), and electroluminescence (EL). ) And other luminescent materials can be used. Among these, a semiconductor laser (LD) and a light emitting diode (LED) are mainly used.
Various types of filters such as a sharp cut filter, a band pass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used to irradiate only light in a desired wavelength range.

The light source or the like irradiates the photoconductor (10) with light by providing a transfer process, a static elimination process, a cleaning process, or a pre-exposure process using light irradiation together. However, the exposure of the photoconductor (10) in the static elimination process has a large influence of fatigue on the photoconductor (10), and may cause a decrease in charge and an increase in residual potential.
Therefore, there is a case where it is possible to eliminate static electricity by applying a reverse bias in the charging process or cleaning process instead of static elimination by exposure, which may be effective from the viewpoint of enhancing the durability of the photoreceptor.

  When the electrophotographic photosensitive member (10) is positively (negatively) charged and image exposure is performed, a positive (negative) electrostatic latent image is formed on the surface of the photosensitive member. A positive image can be obtained by developing this with negative (positive) toner (electrodetection fine particles), and a negative image can be obtained by developing with positive (negative) toner. A known method is applied to the developing unit, and a known method is also used for the charge eliminating unit.

  Among the contaminants that adhere to the surface of the photoconductor, discharge substances generated by charging and external additives contained in the toner are easy to pick up the effects of humidity and cause abnormal images. Paper powder is one of the causative substances, and when they adhere to the photoreceptor, abnormal images are more likely to occur, as well as a tendency to reduce wear resistance and cause uneven wear. Is seen. Therefore, it is more preferable from the viewpoint of high image quality that the photoconductor and the paper are not in direct contact for the above reason.

The toner developed on the photoreceptor (10) by the developing member (13) is transferred to the transfer paper (15), but not all is transferred, and the toner remaining on the photoreceptor (10). Also occurs. Such toner is removed from the photoreceptor (10) by the cleaning member (17).
As the cleaning member, a known member such as a cleaning blade or a cleaning brush is used. Moreover, both may be used together.

  The photoconductor according to the present invention can be applied to a small-diameter photoconductor because high photosensitivity and high stability are realized. Therefore, as an image forming apparatus or method for using the above photoreceptor more effectively, each developing unit corresponding to a plurality of colors of toner is provided with a plurality of corresponding photoreceptors, thereby performing parallel processing. It is very effectively used in a so-called tandem type image forming apparatus. The tandem image forming apparatus includes at least four color toners of yellow (C), magenta (M), cyan (C), and black (K) required for full-color printing and a developing unit that holds them. Further, by providing at least four photoconductors corresponding to them, full-color printing can be performed at an extremely high speed as compared with a conventional image forming apparatus capable of full-color printing.

FIG. 31 is a schematic diagram for explaining the tandem-type full-color electrophotographic apparatus of the present invention, and the following modifications also belong to the category of the present invention.
In FIG. 31, photoconductors (10C (cyan)), (10M (magenta)), (10Y (yellow)), and (10K (black)) are drum-like photoconductors (10), and these photoconductors. (10C, 10M, 10Y, 10K) rotate in the direction of the arrow in the figure, around which at least the charging members (11C, 11M, 11Y, 11K), the developing members (13C, 13M, 13Y, 13K), Cleaning members (17C, 17M, 17Y, 17K) are arranged.

Laser light (12C, 12M) from an exposure member (not shown) from the outside of the photoreceptor (10) between the charging member (11C, 11M, 11Y, 11K) and the developing member (13C, 13M, 13Y, 13K). , 12Y, 12K), and electrostatic latent images are formed on the photoconductors (10C, 10M, 10Y, 10K).
Then, four image forming elements (20C, 20M, 20Y, 20K) centering on such a photoreceptor (10C, 10M, 10Y, 10K) are along a transfer conveyance belt (19) which is a transfer material conveyance means. Are juxtaposed.

  The transfer / conveying belt (19) is disposed between the developing member (13C, 13M, 13Y, 13K) of each image forming unit (20C, 20M, 20Y, 20K) and the cleaning member (17C, 17M, 17Y, 17K). A transfer member (16C) for applying a transfer bias to the surface (rear surface) which is in contact with the photoconductor (10C, 10M, 10Y, 10K) and contacts the back side of the photoconductor (10) side of the transfer conveyance belt (19). , 16M, 16Y, 16K). Each of the image forming elements (20C, 20M, 20Y, 20K) is different in toner color inside the developing device, and the other components have the same configuration.

  In the color electrophotographic apparatus having the configuration shown in FIG. 31, the image forming operation is performed as follows. First, in each of the image forming elements (20C, 20M, 20Y, and 20K), the charging member (11C, 11M, 11Y, and 11K) in which the photosensitive member (10C, 10M, 10Y, and 10K) rotates along with the photosensitive member 10 is rotated. ), And then an electrostatic image corresponding to the image of each color to be created by laser light (12C, 12M, 12Y, 12K) by an exposure unit (not shown) arranged outside the photoconductor (10). A latent image is formed.

  Next, the latent image is developed by a developing member (13C, 13M, 13Y, 13K) to form a toner image. The developing members (13C, 13M, 13Y, and 13K) are developing members that perform development with toners of C (cyan), M (magenta), Y (yellow), and K (black), respectively. 10M, 10Y, and 10K) are overlaid on the transfer belt (19).

  The transfer paper (15) is sent out from the tray by the paper supply roller (21), temporarily stopped by the pair of registration rollers (22), and sent to the transfer member (23) in synchronization with the image formation on the photosensitive member. It is done. The toner image held on the transfer belt (19) is transferred onto the transfer paper (15) by an electric field formed by a potential difference between the transfer bias applied to the transfer member (23) and the transfer belt (19). . The toner image transferred onto the transfer paper is conveyed, the toner is fixed onto the transfer paper by the fixing member (24), and is discharged to a paper discharge unit (not shown). Further, residual toner that is not transferred by the transfer unit and remains on the photosensitive members (10C, 10M, 10Y, and 10K) is collected by cleaning members (17C, 17M, 17Y, and 17K) provided in the respective units. The

The intermediate transfer method as shown in FIG. 31 is particularly effective for an image forming apparatus capable of full-color printing. By forming a plurality of toner images on an intermediate transfer member once and transferring them to paper at once, It is easy to control the color shift and is effective for high image quality.
The intermediate transfer member includes various materials or shapes such as a drum shape and a belt shape. In the present invention, any conventionally known intermediate transfer member can be used. It is effective and useful for achieving high quality or high image quality.

  In the example of FIG. 31, the image forming elements are arranged in the order of Y (yellow), M (magenta), C (cyan), and K (black) colors from the upstream side to the downstream side in the transfer paper conveyance direction. However, it is not limited to this order, and the color order is arbitrarily set. Further, when a black-only document is created, it is particularly effective to use the present invention to provide a mechanism that stops the image forming elements (20C, 20M, 20Y) other than black.

The above-described tandem image forming apparatus can transfer a plurality of toner images at a time, so that high-speed full-color printing is realized.
However, since at least four photoconductors are required, an increase in the size of the apparatus is unavoidable, and depending on the amount of toner used, there is a difference in the wear amount of each photoconductor, thereby reproducing the color. There are many problems such as a decrease in performance and occurrence of abnormal images.
On the other hand, the photosensitive member according to the present invention can be applied to a small-diameter photosensitive member by realizing high photosensitivity and high stability, and the influence of increase in residual potential, sensitivity deterioration, etc. is reduced. Even if the amount of the photoconductor used is different, the difference in residual potential and sensitivity over time is small, and a full color image having excellent color reproducibility can be obtained even when used repeatedly for a long time.

The image forming means as described above may be fixedly incorporated in a copying apparatus, a facsimile, or a printer, but may be incorporated in these apparatuses in the form of a process cartridge.
As shown in FIG. 32, the process cartridge includes a photoconductor (10), a charging member (11), an image exposure member (12), a developing member (13), a transfer member (16), a cleaning member. It is one apparatus (part) including the member (17) and the charge removal member.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to a following example. In addition, all "parts" used in an Example represent a mass part.

[Synthesis example]
Hereinafter, although a synthesis example and an evaluation example are given and this invention is demonstrated further in detail, this invention is not limited to these Examples.
[Synthesis Example 1 (Synthesis of Halogen Intermediate)]
4-Bromobenzyl alcohol: 50.43 g, 3,4-dihydro-2H-pyran: 45.35 g, tetrahydrofuran: 150 ml are placed in a four-necked flask. The mixture was stirred at 5 ° C., and 0.512 g of paratoluenesulfonic acid was dropped. Continue stirring at room temperature for 2 hours. The mixture was extracted with ethyl acetate, dehydrated with magnesium sulfate, and adsorbed with activated clay and silica gel. The target product was obtained by filtration, washing and concentration (yield 72.50 g, colorless oil).
FIG. 1 shows an infrared absorption spectrum (KBr tablet method) of the compound obtained in Synthesis Example 1.

[Synthesis Example 2 (Synthesis of Halogen Intermediate)]
2- (4-Bromobenzyl) ethyl alcohol: 25.05 g, 3,4-dihydro-2H-pyran: 20.95 g, tetrahydrofuran: 50 ml are placed in a four-necked flask. The mixture was stirred at 5 ° C., and 0.215 g of paratoluenesulfonic acid was dropped. Continue stirring at room temperature for 3 hours. The mixture was extracted with ethyl acetate, dehydrated with magnesium sulfate, and adsorbed with activated clay and silica gel. The target product was obtained by filtration, washing and concentration (yield 35.40 g, colorless oil).
FIG. 2 shows an infrared absorption spectrum (KBr tablet method) of the compound obtained in Synthesis Example 2.

[Synthesis Example 3 (Synthesis of Halogen Intermediate)]
4-Bromophenol: 17.3 g, 3,4-dihydro-2H-pyran: 16.83 g, tetrahydrofuran: 100 ml are placed in a four-necked flask. The mixture was stirred at 5 ° C., and 0.172 g of paratoluenesulfonic acid was dropped. Continue stirring at room temperature for 2 hours. The mixture was extracted with ethyl acetate, dehydrated with magnesium sulfate, and adsorbed with activated clay and silica gel. The target product was obtained by filtration, washing and concentration (yield 27.30 g, colorless oil).
FIG. 3 shows an infrared absorption spectrum (KBr tablet method) of the compound obtained in Synthesis Example 3.

[Synthesis Example 4 (Synthesis of Exemplified Compound No. 1)]
4,4′-diaminodiphenylmethane: 2.99 g, Synthesis Example 1 compound: 17.896 g, palladium acetate: 0.336 g, tert-butoxy sodium: 13.83 g, o-xylene: 100 ml are placed in a four-necked flask. Stir at room temperature under argon gas atmosphere. Tritial butylphosphine: 1.214 g was added dropwise. Continue stirring at 80 ° C. for 1 hour and at reflux for 1 hour. Dilute with toluene, add magnesium sulfate, activated clay, silica gel and stir. Filtration, washing and concentration gave a yellow oil. Silica gel column purification (toluene / ethyl acetate = 20/1) was performed and isolated to obtain the desired product (yield 5.7 g, pale yellow amorphous product).
FIG. 4 shows an infrared absorption spectrum (KBr tablet method) of the compound obtained in Synthesis Example 4.

[Synthesis Example 5 (Synthesis of Exemplified Compound No. 8)]
4,4′-Diaminodiphenyl ether: 3.0 g, Synthesis Example 1 Compound: 17.896 g, Palladium acetate: 0.336 g, Tertiary butoxy sodium: 13.83 g, o-xylene: 100 ml are placed in a four-necked flask. Stir at room temperature under argon gas atmosphere. Tritial butylphosphine: 1.214 g was added dropwise. Continue stirring at 80 ° C. for 1 hour and at reflux for 1 hour. Dilute with toluene, add magnesium sulfate, activated clay, silica gel and stir. Filtration, washing and concentration gave a yellow oil. Silica gel column purification (toluene / ethyl acetate = 10/1) was performed and isolated to obtain the desired product (yield 5.7 g, pale yellow oil).
FIG. 5 shows an infrared absorption spectrum (KBr tablet method) of the compound obtained in Synthesis Example 5.

[Synthesis Example 6 (Synthesis of Exemplified Compound No. 12)]
4,4′-ethylenedianiline: 3.18 g, Synthesis Example 1 compound: 17.896 g, palladium acetate: 0.336 g, tert-butoxy sodium: 13.83 g, o-xylene: 100 ml are placed in a four-necked flask. . Stir at room temperature under argon gas atmosphere. Tritial butylphosphine: 1.214 g was added dropwise. Continue stirring at 80 ° C. for 1 hour and at reflux for 1 hour. Dilute with toluene, add magnesium sulfate, activated clay, silica gel and stir. Filtration, washing and concentration gave a yellow oil. Silica gel column purification (toluene / ethyl acetate = 20/1) was performed and isolated to obtain the desired product (yield 5.7 g, pale yellow oil).
FIG. 6 shows an infrared absorption spectrum (KBr tablet method) of the compound obtained in Synthesis Example 6.

[Synthesis Example 7 (Synthesis of Exemplified Compound No. 16)]
α, α′-bis (4-aminophenyl) -1,4-diisopropylbenzene: 10.335 g, Synthesis Example 1 Compound: 39.05 g, Palladium acetate: 0.673 g, Tertiary butoxy sodium: 27.677 g, o -Xylene: 200 ml is placed in a four-necked flask. Stir at room temperature under argon gas atmosphere. Add dropwise 2.43 g of tri-tert-butylphosphine. Continue stirring at 80 ° C. for 1 hour and at reflux for 2 hours. Dilute with toluene, add magnesium sulfate, activated clay, silica gel and stir. Filtration, washing and concentration gave a yellow oil. Silica gel column purification (toluene / ethyl acetate = 10/1) was performed and isolated to obtain the desired product (yield 23.5 g, pale yellow amorphous product).
FIG. 7 shows an infrared absorption spectrum (KBr tablet method) of the compound obtained in Synthesis Example 7.

[Synthesis Example 8 (Synthesis of Exemplified Compound No. 19)]
1,1-bis (4-aminophenyl) cyclohexene: 9.323 g, Synthesis Example 1 Compound: 45.55 g, Palladium acetate: 0.785 g, Tarbutoxy sodium: 32.289 g, o-xylene: 300 ml Place in a mouth flask. Stir at room temperature under argon gas atmosphere. Add dropwise 2.43 g of tri-tert-butylphosphine. Continue stirring at 80 ° C. for 1 hour and at reflux for 2 hours. Dilute with toluene, add magnesium sulfate, activated clay, silica gel and stir. Filtration, washing and concentration gave a yellow oil. Silica gel column purification (toluene / ethyl acetate = 10/1) was performed and isolated to obtain the desired product (yield 11.42 g, yellow amorphous product).
FIG. 8 shows an infrared absorption spectrum (KBr tablet method) of the compound obtained in Synthesis Example 8.

[Synthesis Example 9 (Synthesis of Compound A having 3 or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring of the charge transporting compound)]
Tris (4- (hydroxymethyl) phenyl) amine: 3.4 g, 3,4-dihydro-2H-pyran: 4.65 g, tetrahydrofuran: 100 ml are placed in a four-necked flask. The mixture was stirred at 5 ° C., and 58 mg of paratoluenesulfonic acid was dropped. Continue stirring at room temperature for 5 hours. The mixture was extracted with ethyl acetate, dehydrated with magnesium sulfate, and adsorbed with activated clay and silica gel. Filtration, washing and concentration gave a yellow oily substance. Silica gel column purification (toluene / ethyl acetate = 5/1) was performed and isolated to obtain the desired product. (Yield 2.7 g, pale yellow oil)
FIG. 9 shows an infrared absorption spectrum (liquid film method) of the tetrahydropyranyl compound obtained in Synthesis Example 9.

[Synthesis Example 10 (Synthesis of Compound B having 3 or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring of the charge transporting compound)]
Intermediate methylol compound: 1.274 g, 3,4-dihydro-2H-pyran: 1.346 g, tetrahydrofuran: 20 ml are placed in a four-necked flask. The mixture was stirred at 5 ° C., and 14 mg of paratoluenesulfonic acid was dropped. Continue stirring at room temperature for 4 hours. The mixture was extracted with ethyl acetate, dehydrated with magnesium sulfate, and adsorbed with activated clay and silica gel. Filtration, washing and concentration gave a yellow oily substance. Silica gel column purification (toluene / ethyl acetate = 20/1) was performed and isolated to obtain the desired product (yield 1.48 g, yellow oil).
FIG. 10 shows an infrared absorption spectrum (KBr tablet method) of the compound obtained in Synthesis Example 10.

[Synthesis Example 11 (Synthesis of Compound C used in Comparative Example)]
4,4′-diaminodiphenylmethane: 0.991 g, Synthesis Example 3 Compound: 7.41 g, Tertiary Butoxy Sodium: 3.844 g, Bis (tri-t-butoxyphosphine) palladium: 52 mg, o-xylene: 20 ml Place in a necked flask. Stir at room temperature under argon gas atmosphere. Continue stirring at reflux for 1 hour. Dilute with toluene, add magnesium sulfate, activated clay, silica gel and stir. Filtration, washing and concentration gave a yellow oil. Silica gel column purification (toluene / ethyl acetate = 10/1) was performed and isolated to obtain the desired product (yield 4.12 g, pale yellow amorphous product).
FIG. 11 shows an infrared absorption spectrum (KBr tablet method) of the compound obtained in Synthesis Example 11.

[Synthesis Example 12 (Synthesis of Compound D used in Comparative Example)]
4,4'-diaminodiphenylmethane: 0.991 g, Synthesis Example 4 Compound: 6.603 g, tertiary butoxy sodium: 3.844 g, bis (tri-t-butoxyphosphine) palladium: 52 mg, o-xylene: 20 ml Place in a necked flask. Stir at room temperature under argon gas atmosphere. Continue stirring at reflux for 1 hour. Dilute with toluene, add magnesium sulfate, activated clay, silica gel and stir. Filtration, washing and concentration gave a yellow oil. Silica gel column purification (toluene / ethyl acetate = 20/1) was performed and isolated to obtain the desired product (yield 3.52 g, light yellow powder).
FIG. 12 shows an infrared absorption spectrum (KBr tablet method) of the compound obtained in Synthesis Example 12.

[Synthesis Example 13 (Synthesis of formyl compound used as production raw material of compound E used in Comparative Example)]
4,4′-methylenebis (N, N-diphenylaniline): 30.16 g, N-methylformanilide: 71.36 g, o-dichlorobenzene: 400 ml are placed in a four-necked flask. Stir at room temperature under argon gas atmosphere.
Phosphorus oxychloride: 82.01 g was added dropwise. The temperature was raised to 80 ° C. and stirred. Zinc chloride: 32.71 g was added dropwise. Stirring is performed at 80 ° C. for about 10 hours, and stirring is continued at 120 ° C. for about 3 hours. A potassium hydroxide aqueous solution was added to conduct a hydrolysis reaction. Extraction with dichloromethane, dehydration with magnesium sulfate, and adsorption treatment with activated clay. Filtration, washing, and concentration were performed to obtain a crystalline product. Silica gel column purification (toluene / ethyl acetate = 8/2) was performed and isolated. The obtained crystal was recrystallized from methanol / ethyl acetate to obtain the desired product. (Yield 27.80 g, yellow powder)
FIG. 13 shows an infrared absorption spectrum (KBr tablet method) of the compound obtained in Synthesis Example 13.

[Synthesis Example 14 (Synthesis of Compound E used in Comparative Example)]
The intermediate aldehyde compound obtained in Synthesis Example 13: 12.30 g and ethanol: 150 ml are placed in a four-necked flask. The mixture was stirred at room temperature, and 3.63 g of sodium borohydride was dropped. Continue stirring for 4 hours. The mixture was extracted with ethyl acetate, dehydrated with magnesium sulfate, and adsorbed with activated clay and silica gel. An amorphous substance was obtained by filtration, washing and concentration. The product was dispersed in n-hexane and taken out by filtration, washing, and drying to obtain the desired product (yield 12.0 g, light yellowish white amorphous).
FIG. 14 shows an infrared absorption spectrum (KBr tablet method) of the compound obtained in Synthesis Example 14.

[Synthesis Example 15 (Synthesis of sulfonic acid amine salt SA-1)]
2- (Methylamino) ethanol: 0.375 g (0.005 mol) and methanol: 10 ml are placed in an Erlenmeyer flask. Paratoluenesulfonic acid monohydrate: 0.856 g (0.0045 mol) was added in a water bath, and the mixture was stirred and mixed uniformly. Then, methanol was distilled off under reduced pressure to obtain white crystals. The crude product was washed with THF, filtered and dried to obtain the desired product (paratoluenesulfonic acid amine salt SA-1) (yield 0.94 g, white crystals).
FIG. 15 shows an infrared absorption spectrum (KBr tablet method) of the compound obtained in Synthesis Example 15.

[Synthesis Example 16 (synthesis of sulfonic acid amine salt SA-2)]
1-Amino-2-propanol: 0.375 g (0.005 mol) and methanol: 10 ml are placed in an Erlenmeyer flask. Paratoluenesulfonic acid monohydrate: 0.856 g (0.0045 mol) was added in a water bath, and the mixture was stirred and mixed uniformly. Then, methanol was distilled off under reduced pressure to obtain white crystals. The crude product was washed with THF, filtered and dried to obtain sulfonic acid amine salt SA-2 (yield 0.95 g, white crystals).
FIG. 16 shows an infrared absorption spectrum (KBr tablet method) of the compound obtained in Synthesis Example 16.

[Synthesis Example 17 (synthesis of sulfonic acid amine salt SA-3)]
2- (Dimethylamino) ethanol: 0.446 g (0.005 mol) and methanol: 10 ml are placed in an Erlenmeyer flask. Paratoluenesulfonic acid monohydrate: 0.856 g (0.0045 mol) was added in a water bath, and the mixture was stirred and mixed uniformly. Then, methanol was distilled off under reduced pressure to obtain white crystals. The crude product was washed with THF, filtered and dried to obtain sulfonic acid amine salt SA-3 (yield 0.89 g, white crystals).
FIG. 17 shows an infrared absorption spectrum (KBr tablet method) of the compound obtained in Synthesis Example 17.

[Synthesis Example 18 (synthesis of sulfonic acid amine salt SA-4)]
Di n-butylamine: 0.646 g (0.005 mol) and methanol: 10 ml are placed in an Erlenmeyer flask. Paratoluenesulfonic acid monohydrate: 0.856 g (0.0045 mol) was added in a water bath, and the mixture was stirred and mixed uniformly. Then, methanol was distilled off under reduced pressure to obtain white crystals. The crude product was washed with n-hexane, filtered and dried to obtain sulfonic acid amine salt SA-4 (yield 1.24 g, white crystals).
FIG. 18 shows an infrared absorption spectrum (KBr tablet method) of the compound obtained in Synthesis Example 18.

[Synthesis Example 19 (Synthesis of sulfonic acid amine salt SA-5)]
Triethylamine: 0.506 g (0.005 mol) and methanol: 10 ml are placed in an Erlenmeyer flask. Paratoluenesulfonic acid monohydrate: 0.856 g (0.0045 mol) was added in a water bath, and the mixture was stirred and mixed uniformly. Then, methanol was distilled off under reduced pressure to obtain white crystals. The crude product was washed with THF, filtered and dried to obtain sulfonic acid amine salt SA-5 (yield 1.19 g, white crystals).
FIG. 19 shows an infrared absorption spectrum (KBr tablet method) of the compound obtained in Synthesis Example 19.

[Synthesis Example 20 (Synthesis of sulfonic acid amine salt SA-6)]
2- (Methylamino) ethanol: 1.50 g (0.020 mol) and methanol: 30 ml are placed in an Erlenmeyer flask. In a water bath, vinyl sulfonic acid (VSA-S, manufactured by Asahi Kasei Finechem): 2.16 g (0.020 mol) was added, and the mixture was stirred and mixed uniformly. Then, methanol was distilled off under reduced pressure, followed by vacuum drying. As a result, sulfonic acid amine salt SA-6 was obtained (yield 3.31 g, transparent oil).
FIG. 20 shows an infrared absorption spectrum (measured between two NaCl plates) of the compound obtained in Synthesis Example 20.

[Synthesis Example 21 (synthesis of sulfonic acid amine salt SA-7)]
Di-n-butylamine: 2.70 g (0.021 mol) and methanol: 30 ml are placed in an Erlenmeyer flask. In a water bath, vinyl sulfonic acid (VSA-S, manufactured by Asahi Kasei Finechem): 2.16 g (0.020 mol) was added, and the mixture was stirred and mixed uniformly. Methanol was distilled off under reduced pressure to obtain white crystals. Obtained. The crude product was washed with n-hexane, filtered and dried to obtain sulfonic acid amine salt SA-7 (yield 4.58 g, white crystals).
FIG. 21 shows an infrared absorption spectrum (KBr tablet method) of the compound obtained in Synthesis Example 21.

[Synthesis Example 22 (synthesis of sulfonic acid amine salt SA-8)]
2- (Methylamino) ethanol: 0.75 g (0.01 mol) and methanol: 20 ml are placed in an Erlenmeyer flask. In a water bath, dodecylbenzenesulfonic acid: 3.26 g (0.01 mol) was added, and the mixture was stirred and mixed uniformly. Then, methanol was distilled off under reduced pressure and further vacuum dried to obtain sulfonic acid amine salt SA. -8 was obtained (yield 4.05 g, brown oil).
FIG. 22 shows an infrared absorption spectrum of the compound obtained in Synthesis Example 22 (measured between two NaCl plates).

Next, differential thermothermogravimetry (TG / DTA) of the obtained sulfonic acid amine salts SA-1 to SA-8 was performed.
The apparatus used was a differential thermothermal gravimetric simultaneous measurement apparatus (TG / DTA6200) manufactured by Seiko Instruments. The sulfonic acid amine salt SA-1 was placed on an aluminum open sample pan (P / N SSC000E030) and measured. The initial temperature was set at 30 ° C., and nitrogen gas was flowed at a flow rate of 200 ml / min, and the temperature was increased to 500 ° C. at 20 ° C./min.

As an example, FIG. 23 shows the TG / DTA measurement results of the sulfonic acid amine salt SA-1 obtained in Synthesis Example 15. The melting point of sulfonic acid amine salt SA-1 was observed at 67 ° C. Since the melting point of the raw material paratoluenesulfonic acid monohydrate is 100 ° C., it can be said that it is a sulfonic acid amine salt different from the raw material. Moreover, even if it heated to the boiling point (159 degreeC) or more of 2- (methylamino) ethanol which is a raw material, since the weight reduction did not occur, it turned out that 2- (methylamino) ethanol has not volatilized. Note that the decrease in weight near 300 ° C. is due to the decomposition of the sulfonic acid amine salt.
Table 1 shows the melting point read from the TG / DTA measurement and the measurement result of the pH (25 ° C.) in the 0.01 mol / l aqueous solution.

In any of the sulfonic acid amine salts, no volatilization of the amine was observed even when heated to the boiling point of the starting amine or higher.
In the sulfonic acid amine salts SA-6 and SA-8, no endothermic peak due to melting was observed. These are oily and have a melting point below room temperature. The sulfonic acid amine salt SA-7 has high deliquescence and the melting point could not be measured.
The sulfonic acid amine salts SA-1 to SA-7 had a pH of 4 to 7 in a 0.01 mol / l aqueous solution. SA-8 using dodecylbenzenesulfonic acid had a pH of 4 or less. This is probably because dodecylbenzenesulfonic acid has a long-chain alkyl group, and it was difficult to form a salt with an amine.

Next, the synthesis of a comparative sulfonic acid amine salt will be described. An amine was added in excess to the sulfonic acid, and the desired product was taken out without purification as it was to obtain a sulfonic acid amine salt SA-9. Details are shown below.
[Synthesis Example 23 (synthesis of sulfonic acid amine salt SA-9)]
2- (Methylaminoethanol): 1.33 g (0.018 mol) and methanol: 30 ml are placed in an Erlenmeyer flask. In a water bath, paratoluenesulfonic acid monohydrate: 3.05 g (0.016 mol) was added, and the mixture was stirred and mixed uniformly. Then, methanol was distilled off under reduced pressure to obtain white crystals. (Yield 3.50 g, white crystals).
FIG. 24 shows an infrared absorption spectrum (KBr tablet method) of the compound obtained in Synthesis Example 23. The pH in a 0.01 mol / l aqueous solution was 8.8.

Example 1
An undercoating layer coating solution having the following composition, a charge generation layer coating solution having the following composition, and a charge transporting layer coating solution having the following composition are sequentially dip-coated onto a 60 mm diameter surface-polished aluminum cylinder and dried. As a result, an undercoat layer having a thickness of 3.5 μm, a charge generation layer having a thickness of 0.2 μm, and a charge transport layer having a thickness of 22 μm were formed.
On the obtained charge transport layer, a cross-linked charge transport layer coating solution having the following composition is spray-coated, heat-dried at 150 ° C. for 30 minutes, and a cross-linked charge transport layer having a thickness of 6.0 μm is provided. An electrophotographic photoreceptor of the invention was prepared.
Similarly, after a crosslinkable charge transport layer coating solution was prepared, it was placed in a sealed container and stored at 40 ° C. for 30 days. Using the cross-linked charge transport layer coating solution after storage, a sample film for evaluating coating solution stability was prepared by coating and heating and drying on the aluminum cylinder.

[Composition of undercoat layer coating solution]
・ Alkyd resin (Beckosol 1307-60-EL, manufactured by Dainippon Ink & Chemicals, Inc.) ... 6 parts Melamine resin (Super Becamine G-821-60, manufactured by Dainippon Ink & Chemicals, Inc.)
・ ・ ・ 4 parts ・ Titanium oxide (CREL, manufactured by Ishihara Sangyo Co., Ltd.) ・ ・ ・ 50 parts ・ Methyl ethyl ketone ・ ・ ・ 50 parts

[Composition of charge generation layer coating solution]
・ Polyvinyl butyral (XYHL, manufactured by UCC) ・ ・ ・ 0.5 part ・ Cyclohexanone ・ ・ ・ 200 parts ・ Methyl ethyl ketone ・ ・ ・ 80 parts ・ Titanyl phthalocyanine synthesized below ・ 1.5 parts

(Synthesis of titanyl phthalocyanine crystal)
The synthesis was in accordance with Japanese Patent Application Laid-Open No. 2004-83859. That is, 292 parts of 1,3-diiminoisoindoline and 1800 parts of sulfolane are mixed, and 204 parts of titanium tetrabutoxide are added dropwise under a nitrogen stream. After completion of the dropwise addition, the temperature was gradually raised to 180 ° C., and the reaction was carried out by stirring for 5 hours while maintaining the reaction temperature between 170 ° C. and 180 ° C. After the reaction is complete, the mixture is allowed to cool, and then the precipitate is filtered, washed with chloroform until the powder turns blue, then washed several times with methanol, then washed several times with hot water at 80 ° C. and dried. Crude titanyl phthalocyanine was obtained. Crude titanyl phthalocyanine is dissolved in 20 times the amount of concentrated sulfuric acid, added dropwise to 100 times the amount of ice water with stirring, the precipitated crystals are filtered, and then ion-exchanged water (pH: 7.) until the washing solution becomes neutral. 0, specific conductivity: 1.0 μS / cm) Repeated washing with water (pH value of ion-exchanged water after washing was 6.8, specific conductivity was 2.6 μS / cm), wet of titanyl phthalocyanine pigment A cake (water paste) was obtained.

  40 parts of this wet cake (water paste) thus obtained was put into 200 parts of tetrahydrofuran and stirred vigorously (2000 rpm) with a homomixer (Kennis, MARKIIf model) at room temperature, and the dark blue color of the paste turned pale blue. When changed (20 minutes after the start of stirring), stirring was stopped and filtration under reduced pressure was immediately performed. The crystals obtained on the filtration device were washed with tetrahydrofuran to obtain a wet cake of pigment. This was dried under reduced pressure (5 mmHg) at 70 ° C. for 2 days to obtain 8.5 parts of titanyl phthalocyanine crystals. The solid content concentration of the wet cake was 15% by mass. The crystal conversion solvent was used in a mass ratio of 33 times that of the wet cake. The obtained titanyl phthalocyanine powder was subjected to X-ray diffraction spectrum measurement under the following conditions. As a result, the Bragg angle 2θ with respect to the CuKα ray (wavelength 1.542 mm) was 27.2 ± 0.2 °, and the maximum peak and the minimum angle 7.3. It has a peak at ± 0.2 °, and further has major peaks at 9.4 ± 0.2 °, 9.6 ± 0.2 °, 24.0 ± 0.2 °, and 7.3 It was a titanyl phthalocyanine powder having no peak between the peak at ° and the peak at 9.4 °, and further having no peak at 26.3 °. The result is shown in FIG.

<X-ray diffraction spectrum measurement conditions>
X-ray tube: Cu
Voltage: 50kV
Current: 30mA
Scanning speed: 2 ° / min Scanning range: 3 ° -40 °
Time constant: 2 seconds

[Composition of charge transport layer coating solution]
-Bisphenol Z polycarbonate (Panlite TS-2050, manufactured by Teijin Chemicals Ltd.) ... 10 parts-Tetrahydrofuran ... 100 parts-Tetrahydrofuran solution of 1 mass% silicone oil (KF50-100CS, manufactured by Shin-Etsu Chemical Co., Ltd.)・ ・ ・ 0.2 part ・ Low molecular charge transport material represented by the following structural formula 10 parts

[Composition of crosslinking type charge transport layer coating solution]
Compound having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring of the charge transporting compound Exemplified compound No.1 10 parts sulfonic acid amine salt SA-1 ( Acid catalyst) 0.05 parts tetrahydrofuran (dehydrated) 85 parts 2-propanol (dehydrated) 5 parts

(Example 2)
In Example 1, an electrophotographic photoreceptor and a sample film for evaluating coating solution stability were prepared in the same manner as in Example 1 except that the exemplified compound No. 1 was changed to No. 8.
Example 3
In Example 1, an electrophotographic photosensitive member and a coating solution stability evaluation sample film were prepared in the same manner as in Example 1 except that the exemplified compound No. 1 was changed to No. 12.

Example 4
In Example 1, an electrophotographic photosensitive member and a sample film for evaluating coating solution stability were prepared in the same manner as in Example 1 except that the exemplified compound No. 1 was changed to No. 16.
(Example 5)
In Example 1, an electrophotographic photosensitive member and a coating solution stability evaluation sample film were prepared in the same manner as in Example 1 except that the exemplified compound No. 1 was changed to No. 19.

(Example 6)
In Example 1, an electrophotographic photosensitive member and a sample film for evaluating coating solution stability were produced in the same manner as in Example 1 except that the sulfonic acid amine salt SA-1 was changed to SA-2.
(Example 7)
In Example 1, an electrophotographic photosensitive member and a sample film for evaluating coating solution stability were produced in the same manner as in Example 1 except that the sulfonic acid amine salt SA-1 was changed to SA-3.

(Example 8)
In Example 1, the electrophotographic photoreceptor and the coating solution stability were the same as in Example 1, except that the sulfonic acid amine salt SA-1 was SA-4 and the addition amount was 0.06 part. A sample film for evaluation was prepared.
Example 9
In Example 1, an electrophotographic photosensitive member and a sample film for evaluating coating solution stability were prepared in the same manner as in Example 1 except that the sulfonic acid amine salt SA-1 was changed to SA-5.
(Example 10)
In Example 1, the electrophotographic photoreceptor and the coating solution stability were the same as Example 1 except that the sulfonic acid amine salt SA-1 was SA-6 and the addition amount was 0.04 part. A sample film for evaluation was prepared.
(Example 11)
In Example 1, an electrophotographic photosensitive member and a sample film for evaluating coating solution stability were produced in the same manner as in Example 1 except that the sulfonic acid amine salt SA-1 was changed to SA-7.

(Example 12)
In Example 1, Exemplified Compound No. 1 was changed to Compound A having three [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring of the following charge transporting compound. In the same manner as above, an electrophotographic photosensitive member and a sample film for evaluating coating solution stability were prepared.

(Example 13)
Example 1 except that Exemplified Compound No. 1 in Example 1 was Compound B having four [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring of the following charge transporting compound. In the same manner as above, an electrophotographic photosensitive member and a sample film for evaluating coating solution stability were prepared.

(Comparative Example 1)
In Example 1, an electrophotographic photosensitive member and a sample film for evaluating the stability of the coating solution were prepared in the same manner as in Example 1 except that the crosslinking charge transport layer coating solution had the following composition.
[Composition of crosslinking type charge transport layer coating solution]
Compound having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring of the charge transporting compound Exemplary compound No. 1 10 parts Paraparatoluenesulfonic acid monohydrate (Acid catalyst) ... 0.02 part · Tetrahydrofuran (dehydration) ... 90 parts

(Comparative Example 2)
In Example 1, except that sulfonic acid amine salt SA-1 was changed to p-toluenesulfonic acid pyridinium salt (manufactured by Tokyo Chemical Industry Co., Ltd., pH was 3.3 when 0.01 mol / l aqueous solution was used). In the same manner as in Example 1, an electrophotographic photosensitive member and a sample film for evaluating coating solution stability were produced.

(Comparative Example 3)
In Example 1, the electrophotographic photoreceptor and the coating solution stability were the same as in Example 1 except that the sulfonic acid amine salt SA-1 was SA-8 and the addition amount was 0.08 part. A sample film for evaluation was prepared.
(Comparative Example 4)
In Example 1, an electrophotographic photosensitive member and a sample film for evaluating coating solution stability were produced in the same manner as in Example 1 except that the sulfonic acid amine salt SA-1 was changed to SA-9.

(Comparative Example 5)
In Example 1, 10 parts of a compound (specific example No. 1) having four [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring of the charge transporting compound was mixed with 90 parts of tetrahydrofuran (dehydrated). Then, 0.024 part of paratoluenesulfonic acid monohydrate (acid catalyst) and 0.016 part of 2- (methylamino) ethanol are added and stirred, and a crosslinking type charge transport layer coating solution is added. Except that, an electrophotographic photosensitive member and a sample film for evaluating coating solution stability were prepared in the same manner as in Example 1.

(Comparative Example 6)
In Example 1, an electrophotographic photosensitive member and a sample film for evaluating coating solution stability were prepared in the same manner as in Example 1 except that the exemplified compound No. 1 was changed to the charge transporting compound C having the following structure. did.

(Comparative Example 7)
In Example 1, an electrophotographic photosensitive member and a coating film stability evaluation sample film were prepared in the same manner as in Example 1 except that the exemplified compound No. 1 was changed to the charge transporting compound D having the following structure. did.

(Comparative Example 8)
In Example 1, the electrophotographic photosensitive member and the coating liquid were obtained in the same manner as in Example 1 except that the exemplified compound No. 1 was changed to the compound E having four methylol groups on the aromatic ring of the charge transporting compound. A sample film for stability evaluation was prepared.

(Comparative Example 9)
In Example 1, an electrophotographic photosensitive member and a coating film stability evaluation sample film were prepared in the same manner as in Example 1 except that the exemplified compound No. 1 was changed to the charge transporting compound F having the following structure. did.

(Comparative Example 10)
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the composition of the crosslinking charge transport layer coating solution was changed as follows.
[Composition of crosslinking type charge transport layer coating solution]
Charge transporting compound Charge transporting compound F used in Comparative Example 9 5.5 parts Resol type phenol resin PL-2211 (manufactured by Gunei Chemical Co., Ltd.) 7 parts Amine sulfonate SA- 1 (acid catalyst) ... 0.1 part, isopropanol ... 15 parts, methyl ethyl ketone ... 5 parts (Comparative Example 11)
In Example 1, an electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the crosslinkable charge transport layer was not provided.

<Solubility test, surface smoothness measurement>
In order to examine whether a three-dimensional crosslinked film was formed on the crosslinked charge transport layer, a solubility test was performed with tetrahydrofuran. In the solubility test, the surface of the photoreceptor was rubbed with a cotton swab dipped in tetrahydrofuran, and the presence or absence of deformation was visually observed. The case where no trace was found after rubbing was evaluated as “insoluble”, the case where the film remained but the trace remained was evaluated as “partially dissolved”, and the case where the film was dissolved was evaluated as “dissolved”.
Further, the surface smoothness of the cross-linkable charge transport layer was determined by a ten-point average roughness (Rz) value according to JIS-'82 standard using a surface roughness shape measuring instrument (Surfcom 1400D manufactured by Tokyo Seimitsu Co., Ltd.). The cross-linked charge transport layer of the electrophotographic photosensitive member was initially stored after the coating solution stability evaluation sample film was stored.
The results are shown in Table 3. In Table 3, pH indicates the pH of an acid catalyst in a 0.01 mol / l aqueous solution. Since Comparative Example 11 was not provided with a cross-linked charge transport layer, it was excluded from the solubility test and surface smoothness measurement.

Cured films of Examples 1 to 13 in which a compound having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring of the charge transporting compound of the present invention was polymerized with a sulfonic acid amine salt Had good reactivity and became insoluble in the solubility test. Further, even when the coating solution was stored for 30 days, a uniform coating film could be obtained.
On the other hand, Comparative Example 1 using p-toluenesulfonic acid monohydrate as an acid catalyst and Comparative Example 2 using a sulfonic acid amine salt having a pH of 4 or less were insoluble in the solubility test, but stored for 30 days. The surface smoothness of the sample film prepared with the later coating solution was poor. This is probably because the curing reaction progressed during storage of the coating solution and the reaction during coating became non-uniform.
Similarly, Comparative Example 3 using the sulfonic acid amine salt SA-8 synthesized using dodecylbenzenesulfonic acid was insoluble in the solubility test, but the sample film prepared with the coating solution after storage was used. The surface smoothness was poor.
Comparative Example 4 using sulfonic acid amine salt SA-9 having a pH of 0.01 or more at 0.01 mol / l was insoluble in the solubility test, and the surface smoothness after storage was also good.
Moreover, also in Comparative Example 5 in which p-toluenesulfonic acid monohydrate and amine were separately added to the coating solution, the surface smoothness was poor. When para-toluenesulfonic acid and amine are added separately, the formation of para-toluenesulfonic acid amine salt is inhibited due to the coordination of para-toluenesulfonic acid to the nitrogen atom of the charge transporting compound and the influence of the solvent. It is thought that it has been done.
Comparative Examples 6, 7, and 9 using a charge transporting compound that is not a compound having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring of the charge transporting compound are the solubility tests. It was found that a three-dimensional cross-linked film having a high cross-linking density was not obtained by dissolution or partial dissolution.

<Image output evaluation>
The electrophotographic photosensitive members produced in Examples 1 to 13 and Comparative Examples 1 to 5, 8, 10, and 11 were evaluated for mechanical characteristics, electrical characteristics, environmental characteristics, and gas resistance. The mechanical characteristics of the Ricoh digital full-color MFP MP C7500 SP are mounted on the electrophotographic photosensitive member obtained from the process cartridge, attached to the main body, and A4 paper of Ricoh My Recycle Paper GP is used at a resolution of 600 × 600 dpi. , Magenta, cyan, and black halftone test patterns were continuously output at 500 sheets at a printing speed of 60 sheets per minute, and the amount of photoconductor wear after a total of 100,000 sheets was printed. It evaluated by measuring.
In addition, the presence or absence of abnormal images such as background stains and streaky stains after printing 100,000 sheets was observed.
The electrical characteristics were evaluated by measuring the in-machine bright part potential (VL potential) reflecting the sensitivity characteristics and residual potential characteristics at the initial stage and after printing 100,000 sheets.

Environmental characteristics are as follows. The image output device is placed in a high-temperature and high-humidity room at 30 ° C. and 90 RH%, 50 images are output continuously, and the image density of the 50th halftone pattern portion (1 by 1 dot black image portion) Was measured by a Macbeth densitometer, and dot reproducibility was evaluated.
In addition, the gas resistance is obtained by exposing the produced electrophotographic photosensitive member to a NOx gas exposure device for 4 days under the condition of 5 ppm NO gas / 20 ppm NO ₂ gas, and then outputting 50 consecutive images to obtain the 50th image. This was performed by measuring the image density of the halftone pattern portion (1 by 1 dot black image portion) with a Macbeth densitometer and evaluating the dot reproducibility. Both environmental characteristics and gas resistance evaluation were determined according to the following indices.
Good: Concentration 0.45 to 0.35, slight decrease: Concentration 0.35 to 0.25,
Decrease: Concentration 0.25-0.15, Large reduction: Concentration 0.15-0
In addition, it is clear that each of the electrophotographic photoreceptors of Comparative Examples 6, 7, and 9 dissolved or partially dissolved in the solubility test does not have strong three-dimensional crosslinking. Therefore, it is difficult to obtain satisfactory wear resistance over a long period of time, and was not evaluated. The results are shown in Table 4.

From the results of Table 4, the electrophotographic photoreceptors of the present invention of Examples 1 to 11 have excellent electrical characteristics with high wear resistance and little increase in bright part potential, and also environmental characteristics and gas resistance. It was also found that this is a highly durable electrophotographic photosensitive member.
Examples 10 and 11 using sulfonic acid amine salts SA-6 and 7 synthesized using vinyl sulfonic acid have particularly low light part potential and very little change in light part potential. It was found to be an electrophotographic photoreceptor excellent in. The detailed mechanism is not clear, but I guess as follows.
Vinylsulfonic acid does not have an aromatic ring and has a simple structure as compared with p-toluenesulfonic acid, and side reactions are unlikely to occur. For this reason, it is considered that the generation of a polar substance that becomes a trap site is suppressed, and excellent electrical characteristics are exhibited.
Example 12 Using Compound A Having Three or More [(Tetrahydro-2H-pyran-2-yl) oxy] methyl Groups on the Aromatic Ring of the Charge Transporting Compound Other than the Compound Represented by Formula (2) However, the light portion potential is slightly high and the wear resistance is slightly inferior. In addition, an implementation using a compound having four [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups on the aromatic ring of the charge transporting compound and linking two triphenylamine structures in a conjugate manner In Example 13, although the abrasion resistance was high and the bright part potential was low, a decrease in image density was observed in the environmental characteristics and gas resistance evaluation. A charge transporting compound in which two triphenylamine structures are conjugatedly connected has a low oxidation potential and is considered to be less stable than the compound represented by the general formula (2).

Comparative Example 1 using p-toluenesulfonic acid monohydrate and Comparative Examples 2 and 3 using a sulfonic acid amine salt having a pH of less than 4 were poor in environmental characteristics and gas resistance.
In Comparative Example 4 using the sulfonic acid amine salt SA-9, the bright part potential is high and the wear resistance is also inferior. Since the pH at 0.01 mol / l exceeds 7, a large amount of amine component is contained, which inhibits curing, and it is thought that the bright part potential has increased due to remaining amine more than necessary. It is done.
Comparative Example 5 in which p-toluenesulfonic acid monohydrate and amine were separately added had poor environmental characteristics and gas resistance. When paratoluenesulfonic acid monohydrate and amine are added separately, the paratoluenesulfonic acid amine salt is difficult to form and the amine volatilizes during heating, so that the paratoluenesulfonic acid is neutralized after curing. Therefore, it is thought that the environmental characteristics and gas resistance were lowered.

In Comparative Example 8 using a methylol compound, although the abrasion resistance was high, the environmental characteristics and gas resistance were very poor due to the unreacted hydroxyl group. Similarly, Comparative Example 10 to which a phenol resin having a hydroxyl group was added also had poor environmental characteristics and gas resistance.
In Comparative Example 11 in which no protective layer was provided, wear was significant and soiling occurred, so environmental characteristics and gas resistance were not evaluated.

  As shown in the embodiment, the image forming method, the image forming apparatus, and the process cartridge for the image forming apparatus using the electrophotographic photosensitive member of the present invention can continuously output a high-quality image output over a long period of time. In addition, a high-quality image can be output stably even in an environment where environmental fluctuations, oxidizing gas, and the like are generated.

1: Conductive support 2: Charge generation layer 3: Charge transport layer 4: Undercoat layer 5: Cross-linked charge transport layer 6: Single layer photosensitive layer containing both charge generation material and charge transport material 7: Single layer photosensitivity Surface layer for layer 10, 10Y, 10M, 10C, 10K: photoconductor 11, 11Y, 11M, 11C, 11K: charging member 12, 12Y, 12M, 12C, 13K: image exposure member 13, 13Y, 13M, 13C, 13K : Development member 14: Conveying roller 15: Transfer paper 16, 16Y, 16M, 16C, 16K: Transfer member 17, 17Y, 17M, 17C, 17K: Cleaning member 18: Static elimination member 19: Transfer belt 20Y, 20M, 20C, 20K : Image forming element 21: Paper feed roller 22: Registration roller 23: Transfer member (secondary transfer member)
24: Fixing member

JP-A-56-048637 JP-A 64-001728 Japanese Patent Laid-Open No. 04-281461 Japanese Patent No. 3262488 Japanese Patent No. 3194392 JP 2000-66425 A Japanese Patent Laid-Open No. 06-118681 JP 09-124943 A Japanese Patent Laid-Open No. 09-190004 JP 2000-171990 A JP 2003-186223 A JP 2007-293197 A JP 2008-299327 A Japanese Patent No. 4262061 JP 2006-251771 A JP 2009-229549 A JP 2006-84711 A

Claims (5)

Have at least a photosensitive layer on an electroconductive substrate, in the manufacturing method of the electrophotographic photosensitive member outermost surface layer is made of three-dimensionally crosslinked film of the photosensitive layer, the three-dimensional crosslinked film, a vinyl sulfonic acid and an amine A vinylsulfonic acid amine salt obtained by reaction, having a pH of 4 or more and 7 or less in 0.01 mol / l aqueous solution of the vinylsulfonic acid amine salt as an acid catalyst, and having an aromatic ring the compound having charge aromatic ring of transporting compound [(tetrahydro -2H- pyran-2-yl) oxy] 3 or more methyl groups, by the acid catalyst, the [(tetrahydro -2H- pyran-2-yl )] A method for producing an electrophotographic photosensitive member , characterized in that it is formed by a reaction in which part of a methyl group is cut off and polymerized. The method for producing an electrophotographic photosensitive member according to claim 1, wherein the amine is represented by the following general formula (1).
(In the formula, R ₁ and R ₂ may be the same or different and each represents hydrogen or an alkyl group having 1 to 5 carbon atoms. R ₃ represents an alkyl group having 1 to 5 carbon atoms which may have a hydroxyl group. Show.) The compound having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups in the aromatic ring of the charge transporting compound having an aromatic ring is represented by the following general formula (2). The method for producing an electrophotographic photosensitive member according to claim 1 or 2 .
(In the formula, X ₁ is an alkylene group having 1 to 4 carbon atoms, an alkylidene group having 2 to 6 carbon atoms, a cycloalkylidene group having 5 or 6 carbon atoms, or an alkylidene having 2 to 6 carbon atoms via a phenylene group. A divalent group in which two groups are bonded, or an oxygen atom, Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ , Ar ₆ has 6 carbon atoms which may have an alkyl group as a substituent. To 18 aromatic hydrocarbon divalent groups.) The compound having three or more [(tetrahydro-2H-pyran-2-yl) oxy] methyl groups in the aromatic ring of the charge transporting compound having an aromatic ring is represented by the following general formula (3). The method for producing an electrophotographic photosensitive member according to claim 3 .
(Wherein, X ₂ is _{-CH 2 -, - CH 2 CH} 2 -, - C (CH 3) 2 -Ph-C (CH 3) 2 -,
Or represents -O-. R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ may be the same or different and each represents a methyl group or an ethyl group, and o, p, q, r, s and t are 0 to 0 Represents an integer of 4. ) 2. The conductive support is provided with at least a charge generation layer, a charge transport layer, and a crosslinkable charge transport layer in this order, and the crosslinkable charge transport layer is the surface layer. The method for producing an electrophotographic photosensitive member according to any one of 4 to 4 .