JPH09190004A - Electrophotographic photoreceptor, process cartridge having the electrophotographic photoreceptor and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an electrophotographic photoreceptor which is free from light scattering and bleeding, is uniform and with which the compatibility of low surface energy with mechanical and electrical durability is attained by incorporating a curable org. silicon high polymer and specific resin into the surface layer of the electrophotographic photoreceptor. SOLUTION: The curable org. silicon high polymer and the resin obtd. by curing the org. silicon denatured hole transferable compd. expressed by the formula are incorporated into the surface layer of the electrophotographic photoreceptor having a photosensitive layer on a substrate. In the formula, A denotes a hole transferable group; Q denotes a hydrolyzable group or hydroxyl group; R<2> denotes a substd. or unsubstd. univalent hydrocarbon group; R<3> denotes a substd. or unsubstd. alkylene group or arylene group; (m) denotes an integer from 1 to 3; 1 denotes a positive integer. The charge transferability in this case refers to the ability to transfer charges and is preferably <=6.2eV in ionization potential.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member having a specific surface layer, a process cartridge having the electrophotographic photosensitive member, and an image forming apparatus.

[0002]

2. Description of the Related Art A charging means,
Since external electrical or mechanical force is directly applied by the developing means, the transferring means, the cleaning means, etc., durability against them is required.

Specifically, durability is required against abrasion and scratches on the surface of the photoconductor due to rubbing, and deterioration of the surface of the photoconductor due to ozone which tends to occur during corona charging under high humidity. In addition, there is a problem that toner adheres to the surface of the photoconductor due to repetition of development and cleaning. For this purpose, improvement in the cleaning property of the surface of the photoconductor is required.

Attempts have been made to provide various surface protective layers containing a resin as a main component in order to satisfy various characteristics required for the surface of the photoreceptor as described above. For example, Japanese Unexamined Patent Publication No.
JP-A-30843 proposes a protective layer in which abrasion resistance and resistance are controlled by adding metal oxide particles as conductive particles.

It has also been studied to improve the physical properties of the photoreceptor surface by adding various substances to the surface layer. For example, as an additive focused on low surface energy of silicone, silicone oil (JP-A-61-13)
2954), polydimethylsiloxane, silicone resin powder (JP-A-4-324454), crosslinked silicone resin, poly (carbonate-silicone) block copolymer, silicone modified polyurethane, silicone modified polyester. .

A typical polymer having a low surface energy is a fluorinated polymer, and examples of the fluorinated polymer include polytetrafluoroethylene powder and fluorinated carbon powder.

[0007]

However, although a surface protective layer containing a metal oxide or the like can have high hardness, it has a problem in cleaning properties and the like because the surface energy is easily increased. Silicone resins are excellent in that they have a small surface energy, but they do not show sufficient compatibility with other resins, so they easily aggregate in the addition system, causing light scattering or bleeding and segregation on the surface. However, there are problems such as not exhibiting stable characteristics. In addition, fluoropolymers, which are low surface energy polymers, are generally insoluble in solvents and have poor dispersibility, making it difficult to obtain a smooth photoconductor surface and having a low refractive index There is a problem that scattering is likely to occur, which causes deterioration of transparency. Further, there is a problem that the fluorine-based polymer is generally soft and easily damaged.

An object of the present invention is to solve the above-mentioned problems, that is, an electrophotographic photosensitive member which is free of light scattering and bleeding, is uniform, and has both low surface energy and mechanical and electrical durability, And to provide a process cartridge and an image forming apparatus having the electrophotographic photosensitive member.

[0009]

That is, the present invention provides an electrophotographic photoreceptor having a photosensitive layer on a support, wherein the surface layer of the electrophotographic photoreceptor is a curable organosilicon polymer and the following formula (1):

[0010]

[Outside 8] (A represents a hole transporting group, Q represents a hydrolyzable group or a hydroxyl group, R ² represents a substituted or unsubstituted monovalent hydrocarbon group, and R ³ represents a substituted or unsubstituted alkylene group or arylene. Represents a group, m represents an integer of 1 to 3, and 1
Represents a positive integer. An electrophotographic photoreceptor comprising a resin obtained by curing an organosilicon-modified hole transporting compound represented by the formula (1).

Further, the present invention is a process cartridge and an image forming apparatus having the above electrophotographic photosensitive member.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION In the above formula (1), Q represents a hydrolyzable group or a hydroxyl group.
Examples thereof include a methoxy group, an ethoxy group, a methylethylketoxime group, a diethylamino group, an acetoxy group, a propenoxy group, a propoxy group, a butoxy group and a methoxyethyl group, and more preferably -OR ¹ . R ¹ is an alkoxy group which is a hydrolyzable group or a group which forms an alkoxyalkoxy group, and preferably has 1 to 6 carbon atoms, for example, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, Hexyl group, methoxyethyl group and the like can be mentioned. As Q, an alkoxy group represented by the formula —OR ¹ is preferable. Generally, when the number m of hydrolyzable groups bonded to a silicon atom is 1, the condensation reaction in the organosilicon compound itself is difficult to occur and the polymerization reaction is suppressed, but when m is 2 or 3, the condensation reaction is Since it is likely to occur and a high degree of crosslinking reaction can be carried out, it is expected to improve the hardness and the like of the obtained cured product, but the solubility and reactivity with the silicon-based thermosetting resin change due to the increase in the molecular weight. It may happen.

R ² is a monovalent hydrocarbon group directly bonded to a silicon atom and preferably has 1 to 15 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group and a pentyl group. To be Besides this, vinyl group,
Examples thereof include alkenyl groups such as allyl group and aryl groups such as phenyl group and tolyl group. Further, examples of the substituent that R ² may have include a halogen atom such as fluorine, and examples of the halogen-substituted monovalent hydrocarbon group include a trifluoropropyl group, a heptafluoropentyl group, a nonafluorohexyl group and the like. Typical examples thereof include fluorohydrocarbon groups.

R ₃ represents an alkylene group or an arylene group, and preferably has 1 to 18 carbon atoms. For example, methylene group, ethylene group, propylene group, cyclohexylidene group, phenylene group, biphenylene group, naphthylene group. Further, a group to which these are bonded may be mentioned. Further, examples of the substituent which R ³ may have include an alkyl group such as a methyl group and an ethyl group, an aryl group such as a phenyl group, and a halogen atom such as a fluorine atom and a chlorine atom. Of these, R ³ is the formula

[0015]

[Outside 9] It is preferable that (n is a positive integer).

It is more preferable that n is from 1 to 18, but it does not necessarily have to be linear. When n is 19 or more, the charge-transporting group A is likely to move, so that the hardness is lowered, and when the charge-transporting group is directly bonded to a silicon atom, stability and physical properties are likely to be adversely affected by steric hindrance or the like. n is preferably 2
８8.

Although 1 represents a positive integer, it is preferably 1 to 5. When 1 is 6 or more, unreacted groups are likely to remain in the curing reaction, so that electric characteristics and the like are likely to be deteriorated.

The charge transport property in the present invention is the ability to transport charges, and the ionization potential is preferably 6.2 eV or less. That is, the organosilicon-modified charge-transporting compound represented by the formula (1) and the hydrogenated product of A have an ionization potential of 6.2 eV.
Or less, particularly 4.5 to 6.2 eV.
It is preferred that The ionization potential is 6.2
If it exceeds eV, hole injection is unlikely to occur and charging becomes easy. If it is less than 4.5 eV, the compound is easily oxidized and thus easily deteriorates. Ionization potential is measured by photoelectron analysis under atmosphere (RIKEN Keiki, surface analyzer AC-1)
Is measured by

Further, the organosilicon-modified hole transporting compound preferably has a hole mobility of drift mobility of 1 × 10 ⁷ cm ² / Vsec or more. 1x1
If it is less than 0 ^-7 cm ² / Vsec, the holes may not move sufficiently after exposure as an electrophotographic photosensitive member before development, so that the sensitivity may be apparently decreased and the residual potential may be increased. .

The hole transporting group A of the above formula (1) is
Any material may be used as long as it exhibits hole transportability.
Examples of the hydrogen addition compound (hole transporting substance) include, for example, oxazole derivatives, oxadiazole derivatives,
Imidazole derivatives, triarylamine derivatives such as triphenylamine, 9- (p-diethylaminostyryl) anthracene, 1,1-bis- (4-dibenzylaminophenyl) propane, styrylanthracene, styrylpyrazoline, phenylhydrazones, Examples thereof include α-phenylstilbene derivatives, thiazole derivatives, triazole derivatives, phenazine derivatives, acridine derivatives, benzofuran derivatives, benzimidazole derivatives, thiophene derivatives, N-phenylcarbazole derivatives.

The hole transporting group A is preferably one having a structure represented by the following formula (2).

[0022]

[Outside 10] (R ⁴ , R ⁵ and R ⁶ are organic groups, at least one of which represents an aromatic hydrocarbon ring group or a heterocyclic group, and R ⁴ , R ⁵ and R ⁶ are the same or different. As described above, the hole-transporting group A is a group formed by removing the hydrogen atom of at least one of R ⁴ , R ⁵ and R ⁶ .

Preferred specific examples of the structures of R ⁴ , R ⁵ and R ⁶ are shown below.

[0024]

[Outside 11]

[0025]

[Outside 12]

[0026]

[Outside 13]

As a method for synthesizing the organosilicon-modified hole-transporting compound of the above formula (1), a known method, for example, platinum from a compound having a vinyl group in the aromatic ring and a silicon hydride compound having a substituent is used. A system catalyst or a catalyst which performs a hydrosilylation reaction using a catalyst such as an organic peroxide is preferably used. The platinum catalyst used in this case is not particularly limited, and a normal hydrosilylation reaction,
Any platinum catalyst used in addition-type silicone rubber may be used, and examples thereof include platinum chloride, chloroplatinic acid, platinum-olefin complex, and platinum-phosphine complex. The amount of the platinum catalyst to be added is not particularly limited, but it is preferable to use the platinum catalyst in the smallest possible amount so that the residual catalyst does not adversely affect the properties. In the case of synthesizing the compound of the present invention from an addition reaction of a compound having a vinyl group in the aromatic ring and a silicon hydride compound having a substituent with a platinum-based catalyst or the like, the case of reacting with the α-position of the vinyl group and β It may react with the position, generally resulting in a mixture. In the present invention, those reacted at both the α-position and the β-position can be used, but when the number of carbon atoms of the hydrocarbon group bonding the silicon atom and the charge transporting group is small, the steric hindrance leads to the β-position. Those that have reacted are preferred.

As the organic peroxide, any organic peroxide having a half-life at room temperature or higher can be used. In particular, an alkyl peroxide such as lauryl peroxide can be suitably used because it does not easily cause hydrogen abstraction. Those not having a vinyl group can be used as the synthetic raw material of the present invention by a method of formylating an aromatic ring, reducing or dehydrating, or directly introducing a vinyl group by a Wittig reaction.

Next, the organosilicon polymer will be described.

Examples of the organosilicon-based polymer include organopolysiloxane, polysilalkylene siloxane, polysilarylene siloxane and the like. Further, the ratio of the number of the monovalent hydrocarbon group bonded to the silicon atom to the number of the silicon atom is preferably 0.5 to 1.5. As the ratio becomes lower at the boundary of 1.0, the composition becomes closer to the glass composition, the weight loss upon heating is small, and the generated resin tends to be hard. When the ratio is less than 0.5, it is difficult to form a film. Further, as the ratio becomes higher than 1.0, the opposite tendency is exhibited. In the case of organopolysiloxane, polydiorganosiloxane is obtained at 2.0, so if it exceeds 1.5, the rubber-like element becomes strong. Too much, the hardness decreases.

As the organopolysiloxane, those having a structural unit represented by the following formula (3) are preferable.

R ⁷ _r SiO _{(4-rs) / 2} (OR ⁸ ) _s (3) (R ⁷ represents a linear or branched alkyl group, an alkenyl group or an aryl group, and R ⁸ represents a hydrogen atom or Represents an alkyl group, and r and s represent a molar ratio.)

In the above formula (3), R ⁷ is a monovalent hydrocarbon group bonded to a silicon atom and has 1 to 18 carbon atoms.
The linear or branched alkyl group is preferably a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a 2-ethylhexyl group, a dodecyl group, an octadecyl group, and the like. Examples of the alkenyl group include a vinyl group and an allyl group, and examples of the aryl group include a phenyl group and a tolyl group. Further, examples thereof include a trifluoropropyl group, a heptafluoropentyl group, and a nonafluorohexyl group. Fluorohydrocarbon groups, chloromethyl groups, chloroethyl groups, and other chlorohydrocarbon groups, and straight-chain or branched saturated hydrocarbon halogen substitutes.

R ⁷ does not necessarily have to be a single type, and is appropriately selected depending on the improvement of resin characteristics, the solubility in a solvent, and the like. It is a well-known fact that in a system in which a methyl group and a phenyl group are mixed, affinity with an organic compound is generally improved as compared with a case where a methyl group is used alone. Further, when a fluorohydrocarbon group is introduced, the surface tension of the organopolysiloxane is reduced by the effect of the fluorine atom in the same manner as in the case of general polymers, and therefore the properties of the organopolysiloxane such as water repellent and oil repellent are improved. Change. Also in the present invention, when a lower surface tension is required, a silicon unit bonded to a fluorohydrocarbon group can be appropriately copolymerized and introduced.

In addition, r represents a molar ratio, and is 0.5 to 0.5 on average.
It is preferably 1.5.

The OR ⁸ group bonded to the silicon atom in the above formula (3) is a hydroxyl group or a hydrolytically condensable group. R ⁸ is selected from hydrogen and lower alkyl groups such as methyl group, ethyl group, propyl group and butyl group. OR
R ⁸ in the ⁸ groups shows the property that the reactivity decreases as the number of carbon atoms in the alkyl group increases from hydrogen, and is appropriately selected according to the reaction system used. The ratio of the groups capable of being hydrolyzed and condensed is indicated by s, and is preferably 0.01 or more. It is well known that the hardness of the resin is adjusted by the crosslink density, and it is also possible in the present invention by controlling the number of the above-mentioned hydrolytically condensable groups bonded to the silicon atom. However, if there are too many hydrolytically condensable groups, there is a possibility that they may remain unreacted, and they will be hydrolyzed in the environment of use, so that the surface characteristics and the like are likely to be adversely affected. A preferred value of s is from 0.01 to 1.5.

One of the general characteristics of organosilicon polymers is that they have very poor affinity and solubility for organic compounds. For example, antioxidants, ultraviolet ray attractants and the like used in ordinary organic resins have no solubility in dimethylpolysiloxane and aggregate in the resin. The charge-transporting compounds that are commonly used are no exception, and it is difficult to dissolve them in a concentration that can be used for the purpose of charge-transporting. However, the charge-transporting compound represented by the formula (1) of the present invention and the organosilicon polymer, particularly the organopolysiloxane, are excellent in compatibility and it is possible to significantly improve mechanical properties.

The organosilicon polymer may be crosslinked by adding a crosslinking agent at the time of curing.

Further, by using a silane compound represented by the following formula (4) as the crosslinking agent, it becomes easy to control the physical properties such as hardness and strength of the surface protective layer obtained by curing the curable composition.

R ⁹ _a SiY _4-a (4) (R ⁹ represents a linear or branched alkyl group, alkenyl group or phenyl group, Y represents a hydrolyzable group, and a represents a molar ratio. .)

In the formula (4), R ⁸ has 1 to 1 carbon atoms.
It is preferably 8, and examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, an amyl group, a hexyl group, a vinyl group, an allyl group, a phenyl group and a tolyl group. Examples of the hydrolyzable group represented by Y include a hydrogen atom, a methoxy group, an ethoxy group, a methylethylketoxime group,
Examples thereof include a diethylamino group, an acetoxy group, a propenoxy group, a propoxy group and a butoxy group.

A catalyst is not necessarily required for the cross-linking and curing of the above resin, but it does not hinder the use of a catalyst used for usual curing of organosilicon polymers, and the time required for curing, the curing temperature, etc. are taken into consideration. Then, it is appropriately selected from alkyltin organic acid salts such as dibutyltin diacetate, dibutyltin dilaurate and dibutyltin octoate, and organic titanate esters such as normal butyl titanate.

Specific examples of the silane compound represented by the formula (4) as a cross-linking agent include, for example, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, phenyltriethoxysilane, and a substitute for these alkoxy groups. Examples thereof include silane substituted with an acetoxy group, a methylethylketoxime group, a diethylamino group and an isopropenoxy group. The cross-linking agent may be in the form of an oligomer such as ethyl polysilicate.

Examples of the method for producing the organosilicon polymer used in the present invention include those described in Japanese Patent Publication No. 26-2696 and Japanese Patent Publication No. 28-6297, and Chemistry and Technology.
y of Silicones, Chapter5
p. 191- (Walter No11, Academ
ic Press, Inc. 1968) organopolysiloxane synthesis method. For example, an organoalkoxysilane or organohalogenosilane having an average number of substitutions r of a monovalent organic group with respect to a silicon atom of 0.5 to 1.5 is dissolved in an organic solvent, and hydrolysis and condensation are performed in the presence of an acid or a base. It is polymerized by removing the solvent and then synthesized. The organic silicon-based polymer used in the present invention is an aromatic hydrocarbon such as toluene or xylene,
It is used by dissolving it in a solvent such as an aliphatic hydrocarbon such as cyclohexanone and hexane, a halogen-containing hydrocarbon such as chloroform and chlorobenzene, an alcohol such as ethanol and butanol.

In the present invention, a three-dimensional crosslinked structure is formed during the curing of the curable organosilicon polymer and the organosilicon-modified hole transporting compound of the present invention, so that the movement between the elements and the external Since it is difficult for the compound to enter, the hardness and mechanical strength increase, and the wear resistance is only improved, and the durability against electrical obstacles such as arc discharge generated during charging and chemical substances is also improved. It becomes possible.

The solution (also referred to as the curable composition of the present invention) before curing the organosilicon polymer and the organosilicon-modified hole transporting compound is obtained, for example, by mixing them in a solvent that dissolves them. To be The organosilicon-modified hole transporting compound is preferably used in a mixture of 20 to 200 parts by weight with respect to 100 parts by weight of the solid content of the organosilicon polymer excluding the solvent. If the amount is less than 20 parts by weight, the hole transporting property becomes insufficient, so that the charging potential is undesirably increased. Also, 2
If it exceeds 100 parts by weight, the mechanical strength is lowered and the surface energy is increased, which is not preferable. More preferably, 30 to 150 parts by weight of the organosilicon-modified hole transporting compound is used with respect to 100 parts by weight of the organosilicon polymer.

In the present invention, the curable polymer may be partially reacted with the organosilicon-modified hole transporting compound in advance. In this case, any solution or dispersion that does not hinder the application to the photoreceptor can be used.

As a curing condition, heating at 100 to 200 ° C. is preferable. If the temperature is less than 100 ° C., the curing reaction takes a long time, and therefore unreacted hydrolyzable groups may remain. If the temperature exceeds 200 ° C., the hole transporting group is liable to be oxidized and deteriorated, and adverse effects are likely to occur. More preferably, it is used after being heated and cured at 120 to 160 ° C.

An example of producing an electrophotographic photosensitive member using the curable composition having a hole-transporting ability of the present invention is shown below.

As the support (1 in FIGS. 1 and 2) of the electrophotographic photosensitive member, the support itself has conductivity, for example, aluminum, aluminum alloy, copper, zinc, stainless steel, chromium, titanium, nickel. , Magnesium, indium, gold, platinum, silver, iron and the like can be used.
In addition, it is possible to use a material in which aluminum, indium oxide, tin oxide, gold, or the like is formed on a dielectric support such as plastic by vapor deposition, or conductive fine particles are mixed with plastic or paper. For these conductive supports, uniform conductivity is required and a smooth surface is important. Since the surface smoothness has a great influence on the uniformity of the undercoat layer, the charge generation layer and the charge transport layer formed thereon, the surface roughness is preferably 0.3 μm or less. The unevenness exceeding 0.3 μm causes a large change in the local electric field applied to a thin layer such as an undercoat layer or a charge generation layer, so that the characteristics of the unevenness greatly change, resulting in charge injection or uneven residual potential. It is not preferable because defects are likely to occur.

Particularly, the conductive layer (2 in FIGS. 1 and 2) obtained by dispersing and coating the conductive fine particles in the polymer binder is easy to form and is suitable for forming a uniform surface. There is. The primary particle diameter of the conductive fine particles used at this time is 100 nm or less, and more preferably 50 nm or less. As the conductive fine particles, conductive zinc oxide, conductive titanium oxide, Al, Au, Cu, Ag,
Co, Ni, Fe, carbon black, ITO, tin oxide, indium oxide, indium, etc. are used, and these may be used by coating the surface of the insulating fine particles. The content of the conductive fine particles is used so that the volume resistance is sufficiently low, and is preferably added so that the resistance is 1 × 10 ¹⁰ Ω · cm or less. More preferably 1 ×
It is used at 10 ⁸ Ω · cm or less.

In order to prevent image deterioration due to interference when exposing using a coherent light source such as a laser,
It is also possible to form irregularities on the surface of the conductive support. At this time, in order to prevent defects such as charge injection and uneven residual potential from occurring, unevenness of about ½ λ of the wavelength used is dispersed with an insulating material such as silica beads having a diameter of several μm or less to obtain a period of 10 μm or less. Can be formed and used.

In the present invention, an undercoat layer (3 in FIGS. 1 and 2) having an injection blocking function and an adhesive function may be provided between the support and the photosensitive layer. Examples of the material of the undercoat layer include casein, polyvinyl alcohol, nitrocellulose, ethylene-acrylic acid copolymer, polyvinyl butyral, phenol resin, polyamide, polyurethane, gelatin and the like. The thickness of the undercoat layer is 0.1
μm to 10 μm is preferable, and particularly 0.3 μm
It is preferably m to 3 μm.

The photosensitive layer has a function consisting of a charge generating layer containing a charge generating substance (4 in FIGS. 1 and 2) and a charge transporting layer containing a charge transporting substance (5 in FIGS. 1 and 2). A separation type or a single layer type (not shown) having a charge generating substance and a charge transporting substance in the same layer is used.

As the charge generating substance, for example, selenium-
Tellurium, pyrylium dye, thiopyrylium dye, phthalocyanine pigment, anthanthrone pigment, dibenzpyrenequinone pigment, pyrantrone pigment, trisazo pigment, disazo pigment, azo pigment, indigo pigment, quinacridone pigment, A cyanine pigment or the like can be used.

The cured product of the curable composition having hole transporting ability of the present invention is used as a charge transporting layer (5 in FIG. 1) or a surface protective layer having hole transporting ability (6 in FIG. 2). It is possible.

When used as a single-layer photoconductor, good characteristics can be obtained by using the charge-generating substance in combination with the curable composition having a hole-transporting ability of the present invention.

The curable composition having a hole-transporting ability of the present invention can be used in combination with another charge-transporting substance. Examples of such a charge-transporting substance include poly-N-vinylcarbazole and polystyrylanthracene. A polymer compound having a heterocyclic ring or a condensed polycyclic aromatic compound such as pyrazoline, imidazole, oxazole, oxadiazole,
Heterocyclic compounds such as triazole and carbazole, triarylalkane derivatives such as triphenylmethane, triarylamine derivatives such as triphenylamine, phenylenediamine derivatives, N-phenylcarbazole derivatives,
Low molecular weight compounds such as stilbene derivatives and hydrazone derivatives can be used.

A binder polymer is used for the charge generating substance and the charge transporting substance, if necessary. Examples of the binder polymer include polymers and copolymers of vinyl compounds such as styrene, vinyl acetate, vinyl chloride, acrylic acid ester, methacrylic acid ester, vinylidene fluoride, trifluoroethylene, polyvinyl alcohol, polyvinyl acetal, and polycarbonate. , Polyester, polysulfone, polyphenylene oxide, polyurethane, cellulose resin, phenol resin, melamine resin, silicon resin, epoxy resin and the like.

In addition to the above-mentioned compounds, additives may be added to the curable composition having a hole-transporting ability of the present invention in order to improve mechanical properties and durability. Such additives include antioxidants, ultraviolet absorbers, stabilizers,
Lubricants, conductivity control agents and the like are used.

The thickness of the charge generation layer in the present invention is 3 μm.
It is preferable that it is below, and it is especially preferable that it is 0.01-1 micrometer. The charge transport layer has a thickness of 1 to 4.
It is preferably 0 μm, and particularly preferably 3 to 30 μm.

When the photosensitive layer is a single layer type, the thickness thereof is preferably 1 to 40 μm, and particularly 3 to 3
It is preferably 0 μm.

The thickness of the surface protective layer in the present invention is 1 to 1
Preferably it is 5 μm. If it is less than 1 μm, the protective effect is not sufficient, and if it exceeds 15 μm, image deterioration is likely to occur due to an increase in the film thickness of the entire photosensitive layer, which is not preferable.

In the present invention, the product of the spot area of the light irradiated by the exposing means and the thickness of the photosensitive layer of the electrophotographic photosensitive member is preferably 2 × 10 ⁴ μm ³ or less. Further, this product is preferably 2 × 10 ³ μm ³ or more in terms of the magnitude of development contrast (potential difference on the photoconductor at the time of development). If it is less than 2 × 10 ³ μm ³ , it tends to be difficult to obtain a sufficient development contrast.

In this case, the exposure method used in the present invention is to form an electrostatic latent image on the photosensitive member by irradiating light in a dot shape. The light source is not particularly limited, but is preferably laser light and LED light in that a smaller spot area can be more easily obtained.

FIG. 3 shows the relationship between the light intensity distribution, the spot diameter, and the product of the light spot area (S) and the thickness of the photosensitive layer.
The light spot generally has an elliptical shape having a main scanning spot diameter (ab) and a sub-scanning spot diameter (cd) as shown in FIG. The product of the heights can be said to be the volume (V) of the portion where the light spot is irradiated on the photosensitive layer.

The spot area (S) of the light is the area on the photosensitive layer, and the light intensity is 1 / e of the peak intensity (A).
² (B) It is represented by the area of the part which is more than. Examples of the light source used include semiconductor lasers and LEDs,
There are Gaussian distributions and Lorentz distributions for the light intensity distribution, but in each case, 1 / e of the peak intensity (A)
² A portion having an intensity higher than (B) is defined as a spot area (S). In addition, the spot area (S) is the position of the photoconductor at CC.
It can be measured by installing a D camera.

The light spot area in the present invention is 4 ×
It is preferably 10 ³ μm ² or less, and particularly 3 × 10
It is preferably ³ μm ² or less. When it exceeds 4 × 10 ³ μm ² , light of adjacent pixels is likely to overlap with each other, and gradation reproducibility is likely to be unstable. Also, in terms of cost, 1 × 10 ³ μm ²
It is preferable that it is above.

From the above viewpoint, the thickness of the photosensitive layer in the present invention is preferably 12 μm or less, and particularly 10
It is preferably not more than μm.

The electrophotographic photosensitive member of the present invention has extremely excellent mechanical strength and surface lubricity, and is therefore very preferable as a photosensitive member used in such a system.

FIG. 4 shows a schematic configuration of a first example of an image forming apparatus having the process cartridge of the present invention.

In the figure, numeral 7 is a drum-shaped electrophotographic photosensitive member of the present invention, which is rotationally driven around a shaft 8 in the direction of the arrow at a predetermined peripheral speed. The photoconductor 7 rotates during the rotation process.
The peripheral surface of the primary charging means 9 is uniformly charged with a predetermined positive or negative potential, and then image exposure light 10 from an image exposure means (not shown) such as laser beam scanning exposure is received. Thus, an electrostatic latent image is sequentially formed on the peripheral surface of the photoconductor 7.

The formed electrostatic latent image is toner-developed by the developing means 11, and the developed toner-developed image is provided between the photoconductor 7 and the transfer means 12 from a paper feeding section (not shown).
Is sequentially transferred to the transfer material 13 which is fed in synchronism with the rotation of.

The transfer material 13 that has undergone the image transfer is separated from the surface of the photoconductor and is introduced into the image fixing means 14 to undergo the image fixing and printed out as a copy to the outside of the apparatus.

The surface of the photoconductor 7 after the image transfer is cleaned by the cleaning means 15 by removing the transfer residual toner, and the pre-exposure light 1 from the pre-exposure means (not shown).
It is used for repeated image formation after being neutralized by No. 6. When the primary charging unit 9 is a contact charging unit using a charging roller or the like, the pre-exposure is not necessarily required.

In the present invention, among the constituent elements such as the electrophotographic photosensitive member 7, the primary charging means 9, the developing means 11 and the cleaning means 15 described above, a plurality of components are integrally combined to form a process cartridge, The process cartridge may be detachably attached to the main body of the image forming apparatus such as a copying machine or a laser beam printer. For example, at least one of the primary charging unit 9, the developing unit 11, and the cleaning unit 15 is integrally supported with the photoconductor 7 to form a cartridge, and the cartridge can be attached to and detached from the apparatus body by using a guide unit such as a rail 18 of the apparatus body. It may be the process cartridge 17.

FIG. 5 shows a schematic structure of a color copying machine which is a second example of the image forming apparatus of the present invention.

In the figure, reference numeral 201 denotes an image scanner section, which is a section for reading a document and performing digital signal processing. Reference numeral 202 denotes a printer unit which prints out an image corresponding to the document image read by the image scanner 201 on a sheet in full color.

In the image scanner unit 201, 20
Reference numeral 0 denotes a mirror-thick plate, which is the original document 20 on the platen glass 203.
4 is irradiated with the light of the halogen lamp 205 that has passed through the infrared cut filter 208, the reflected light from the original is guided to the mirrors 206 and 207, and an image is formed on the 3-line sensor (CCD) 210 by the lens 209. The full-color information is sent to the signal processing unit 211 as red (R), green (G), and blue (B) components. Note that 205 and 2
06 is a velocity v, and 207 is a 1/2 v, which mechanically moves in a direction (sub-scanning direction) perpendicular to the electrical scanning direction (main scanning direction) of the line sensor to scan the entire surface of the document.

The signal processing unit 211 electrically processes the read signal, decomposes it into magenta (M), cyan (C), yellow (Y) and black (BK) components, and sends them to the printer unit 202. . Also, the image scanner unit 2
01, M, C, Y and B per scan of original
One component of K is sent to the printer 202, and a total of 4
One printout is completed by scanning the document once.

The M, C, Y and BK image signals sent from the image scanner unit 201 are sent to the laser driver 212. The laser driver 212 modulates and drives the semiconductor laser 213 according to the image signal. The laser light scans the photoconductor 217 via the polygon mirror 214, the f-θ lens 215, and the mirror 216.

Reference numeral 218 denotes a rotary developing device, which includes a magenta developing device 219, a cyan developing device 220, and a yellow developing device 221.
And a black developing device 222. The four developing devices alternately contact the photoconductor and develop the electrostatic latent images of M, C, Y and BK formed on the photoconductor 217 with the corresponding toners.

Reference numeral 223 denotes a transfer drum, which is the paper cassette 22.
4 or 225 to the transfer drum 2
23, and the toner image developed on the photoconductor 217 is transferred onto a sheet.

After the four colors of M, C, Y and BK have been sequentially transferred in this manner, the paper passes through the fixing unit 226 and is discharged.

Next, a synthesis example of the curable organosilicon polymer used in the present invention will be shown.

[0086]

【Example】

[Synthesis Example 1] Preparation of curable resin solution containing methyl polysiloxane resin as a main component 10 g of methyl polysiloxane resin containing 1% by weight of silanol group consisting of 80 mol% of methyl siloxane unit and 20 mol% of dimethyl siloxane unit in toluene It was dissolved in 10 g, and 5.3 g of methyltrimethoxysilane and 0.2 g of dibutyltin diacetate were added thereto to make a uniform solution.

[Synthesis Example 2] Preparation of curable resin solution containing methylpolysiloxane resin as a main component 1% by weight of silanol group-containing methylpolysiloxane resin consisting of 80% by mole of methylsiloxane unit and 20% by mole of dimethylsiloxane unit 10 g of toluene was dissolved in 10 g of toluene, and methyltri (methylethylketoxime) was added to the solution.
11.5 g of silane and 0.2 g of dibutyltin diacetate were added to make a uniform solution.

[Synthesis Example 3] Preparation of curable resin solution containing methylphenylpolysiloxane resin as a main component 40 mol% of phenylsiloxane units, 20 mol% of diphenylsiloxane units, 20 mol% of methylsiloxane units, 20 mol of dimethylsiloxane units % Of 1% by weight of silanol group-containing methylphenylpolysiloxane resin was dissolved in 10 g of toluene, and 0.2 g of dibutyltin diacetate was added to form a uniform solution.

[Synthesis Example 4] Preparation of curable resin solution containing fluorosilicone resin as main component 50 mol% of methyl siloxane unit, 10 mol% of dimethyl siloxane unit, 3,3,4,4,5,5,6,6 6,6
10 g of a methylnonafluorohexylpolysiloxane resin containing 1% by weight of silanol groups consisting of 10 mol% of nonafluorohexylsiloxane units was dissolved in 10 g of toluene, and 0.2 g of dibutyltin diacetate was added thereto to form a uniform solution. did.

Next, a synthesis example of the organosilicon-modified hole-transporting compound used in the present invention will be shown.

[Synthesis Example 5] Synthesis of 4- [2- (triethoxysilyl) ethyl] triphenylamine <Synthesis of 4- (N, N-diphenylamino) benzaldehyde> Triphenylamine 101.
4 g and 35.5 ml of DMF were added, and 84.4 ml of phosphorus oxychloride was added dropwise with stirring under ice-water cooling.
The mixture was heated to 5 ° C. and reacted for 5 hours. The reaction solution was poured into 4 liters of warm water and stirred for 1 hour. After that, the precipitate is filtered off,
After washing with a mixed solution of ethanol / water (1: 1),
(N, N-diphenylamino) benzaldehyde was obtained. Yield 91.5 g (81.0% yield).

<Synthesis of 4-vinyltriphenylamine>
Sodium hydride (14.6 g) and 1,2-dimethoxyethane (700 ml) were placed in a three-necked flask, and trimethylphosphonium bromide (130.8 g) was stirred at room temperature.
Was added. Then, after adding one drop of absolute ethanol, 70
The reaction was performed at 4 ° C. for 4 hours. 4- (N, N-diphenylamino) benzaldehyde 100g was added to this, the temperature was raised to 70 degreeC, and it was made to react for 5 hours. The reaction solution was filtered, and the filtrate and the ether extract of the precipitate were combined and washed with water. Then
After dehydrating the ether solution with calcium chloride, the ether was removed to obtain a reaction mixture. This was recrystallized from ethanol to obtain acicular, pale yellow vinyltriphenylamine. Yield 83.4 g (84.0% yield).

<Hydrosilylation of 4-vinyltriphenylamine> Toluene 40 ml, triethoxysilane 9.
9 g (60 mmol) and 0.01 solution of tris (tetramethyldivinyldisiloxane) diplatinum (0) in toluene
8 mmol was placed in a three-necked flask, and 20 ml of a toluene solution of 8.2 g of 4-vinyltriphenylamine was added dropwise with stirring at room temperature. After completion of the dropwise addition, the mixture was stirred at 70 ° C. for 3 hours, and then the solvent was removed under reduced pressure.
[2-Triethoxysilyl) ethyl] triphenylamine was obtained. Yield 12.1 g (91.7% yield).

The H-NMR spectrum is shown in FIG. 6 (APC300 NMR spectrometer manufactured by Bruker).
The ionization potential of this compound was 5.68 eV when measured by a photoelectron analysis method (manufactured by Riken Keiki, surface analyzer AC-1) in the atmosphere.

This compound was applied on a copper substrate by the wire bar coating method and heat-cured at 120 ° C. for 12 hours to form a film of about 8 μm. Next, a translucent gold electrode was formed by vapor deposition.

Pulse width 3 nsec for this sample
-O using a nitrogen laser with a wavelength of 337 nm
When the drift mobility was measured by the f-flight method, it was 1 × 10 ⁻⁷ cm ² / Vsec.

[Synthesis Example 6] Synthesis of 4- [2- (methyldiethoxysilyl) ethyl] triphenylamine <Hydrosilylation of 4-vinyltriphenylamine> 40 ml of toluene, 8.1 g of methyldiethoxysilane and tris ( 0.018 mmol of a toluene solution of tetramethyldivinyldisiloxane) diplatinum (0) was placed in a three-necked flask, and 20 ml of a toluene solution of 4-vinyltriphenylamine (8.2 g) was added dropwise with stirring at room temperature. After completion of dropping, the mixture was stirred at 70 ° C. for 3 hours, and then the solvent was removed under reduced pressure to obtain pale yellow oily 4- [2- (methyldiethoxysilyl) ethyl] triphenylamine. Yield 11.2
g (yield 91.4%).

The ionization potential of this compound was measured by a photoelectron analysis method under atmospheric conditions (manufactured by Riken Keiki, surface analyzer AC-1).
Was 5.66 eV.

This compound was applied on a copper substrate by the wire bar code method and heat-cured at 120 ° C. for 12 hours to form a film of about 5 μm. Next, a translucent gold electrode was formed by vapor deposition.

Pulse width 3 nsec for this sample
-O using a nitrogen laser with a wavelength of 337 nm
When the drift mobility was measured by the f-light method, it was 1.2 × 10 ⁻⁷ cm ² / Vsec.

Synthesis Example 7 4,4 ′, 4 ″ -Tris [2- (triethoxysilyl)
Synthesis of ethyl] triphenylamine <Synthesis of tri (4-formylphenyl) amine> In a three-necked flask, 50.7 g of triphenylamine and DMF5 were added.
3.3 ml was added, and 126.6 ml of phosphorus oxychloride was added dropwise with stirring under cooling with ice water. After completion of dropping, the mixed solution was reacted at 95 ° C. for 5 hours, poured into 5 liters of warm water, and stirred for 1 hour. After that, the precipitate is filtered and ethanol /
It was washed with a mixed solution of water (1: 1) to obtain tri (4-formylphenyl) amine. Yield 65.3 g (yield 95.
9%).

<Synthesis of tri (4-vinylphenyl) amine> Sodium hydride (14.6 g) and 1,2-dimethoxyethane (70 ml) were placed in a three-necked flask, and trimethylphosphonium bromide (130.8) was stirred at room temperature.
g was added. Next, after adding a drop of absolute ethanol, 7
The reaction was carried out at 0 ° C for 4 hours. The reaction mixture obtained as described above was added with tri (4-formylphenyl) amine 40.
After adding 2 g and reacting at 70 ° C. for 5 hours, the mixture was filtered, and the filtered cake was extracted with ether, combined with the filtered solution, and washed with water. Next, the ether solution was dehydrated with calcium chloride, and the ether was removed to obtain a reaction mixture. This was recrystallized twice with ethanol to obtain needle-shaped, pale yellow tri (4-vinylphenyl) amine. Yield 38.4 g (Yield 9
7.3%).

<Hydrosilylation of tri (4-vinylphenyl) amine> 40 ml of toluene, 9.9 g (60 mmol) of triethoxysilane and tris (tetramethyldivinyldisiloxane) diplatinum (0) in toluene solution of 0.
018 mmol was placed in a three-necked flask, and tri (4-vinylphenyl) amine 3.3 g (1
20 ml of a 3 mmol) toluene solution was added dropwise. After completion of dropping, the mixture was stirred at 70 ° C. for 3 hours, and then the solvent was removed under reduced pressure to obtain pale yellow oily 4,4 ′, 4 ″-[2- (triethoxysilyl) ethyl] triphenylamine. It was
Yield 7.8 g (80.6% yield).

The ionization potential of this compound was measured by a photoelectron analysis method under atmospheric conditions (manufactured by Riken Keiki, surface analyzer AC-1).
Was 5.65 eV.

This compound was applied to a copper substrate by the wire bar code method and heat-cured at 120 ° C. for 12 hours to give about 5
A μm film was prepared. Next, a translucent gold electrode was formed by vapor deposition.

Pulse width 3 nsec for this sample
-O using a nitrogen laser with a wavelength of 337 nm
The drift mobility measured by the f-flight method was 3 × 10 ⁻⁷ cm ² / Vsec.

[Synthesis Example 8] Synthesis of 4- [N, N-bis (3,4-dimethylphenyl) amino]-[2- (triethoxysilyl) ethyl] benzene <N, N-bis (3,4) -Synthesis of dimethylphenyl) aminobenzene> 4-iodo-o-xylene 38.5 g
(166 mmol), 22.9 g of anhydrous potassium carbonate (1
66 mmol) and 7.0 g of copper powder in nitrobenzene 20
The mixture was added to ml and heated under reflux with stirring for 8 hours. After cooling, it was filtered and the precipitate was removed. The obtained reaction mixture was passed through a silica gel column to obtain N, N-bis (3,4-dimethylphenyl) aminobenzene. Yield 15.7 g (yield 69
%).

<Synthesis of 4- [N, N-bis (3,4-dimethylphenyl) amino] benzaldehyde> [N, N-bis (3,4-dimethylphenyl)] was added to a three-necked flask.
Amino] benzene 124.6 g and DMF 35.5 ml were put, and phosphorus oxychloride 84.
4 ml was added dropwise. After the dropping is completed, the mixed solution is heated at 95 ° C for 5 hours.
The mixture was allowed to react for 4 hours, poured into 4 liters of warm water, and stirred for 1 hour. Then, the precipitate was filtered off and ethanol / water (1:
It was washed with the mixed solution of 1), and 4- [N, N-bis (3,4
-Dimethylphenyl) amino] benzaldehyde was obtained. Yield 107.6 g (79.0% yield).

<Synthesis of 4- [N, N-bis (3,4-dimethylphenyl) amino] styrene> 12.1 g of sodium hydride and 580 ml of 1,2-dimethoxyethane were placed in a three-necked flask and kept at room temperature. 108.5 g of trimethylphosphonium bromide was added with stirring. Next, one drop of absolute ethanol was added, and the mixture was reacted at 70 ° C. for 4 hours. 4- [N,
After 100.0 g of N-bis (3,4-dimethylphenyl) amino] benzaldehyde was added and the mixture was reacted at 70 ° C. for 5 hours, it was filtered, and the filtered cake was extracted with ether, combined with the filtered solution, and washed with water. Next, the ether solution was dehydrated with calcium chloride, and the ether was removed to obtain a reaction mixture.
This was recrystallized twice with ethanol, and needle-shaped, 4- [N,
N-bis (3,4-dimethylphenyl) amino] styrene was obtained. The yield was 84.5 g (85.0% yield).

<Hydrosilylation of 4- [N, N-bis (3,4-dimethylphenyl) amino] styrene> Toluene 40 ml, triethoxysilane 6.0 g and tris (tetramethyldivinyldisiloxane) diplatinum (0) 0.54 mmol of a toluene solution of 4 [N, N-bis (3,4-
20 ml of a toluene solution of 9.9 g of dimethylphenyl) amino] styrene was added dropwise. After completion of dropping, the mixture was stirred at 70 ° C. for 3 hours, the solvent was removed under reduced pressure, and a pale yellow oily 4- [N, N-bis (3,4-dimethylphenyl) amino]-[2- ( Triethoxysilyl) ethyl] benzene was obtained. Yield 13.4 g (90.1% yield).

The H-NMR spectrum is shown in FIG. (APC300 NMR spectrometer manufactured by Bruker)
The C-NMR spectrum is shown in FIG. (Made by Bruker,
APC300 NMR spectrometer) The ionization potential of this compound was measured by a photoelectron analysis method (manufactured by Riken Keiki, surface analyzer AC-1) in the atmosphere.
It was 26 eV.

This compound was applied on a copper substrate by the wire bar coating method and heat-cured at 120 ° C. for 12 hours to form a film of about 5 μm. Next, a translucent gold electrode was formed by vapor deposition.

Pulse width 3 nsec for this sample
-O using a nitrogen laser with a wavelength of 337 nm
When the drift mobility was measured by the f-light method, it was 9 × 10 ⁻⁷ cm ² / Vsec.

[Synthesis Example 9] Synthesis of 4- [N, N-bis (3,4-dimethylphenyl) amino]-[2- (triethoxysilyl) ethyl] benzene <4- [N, N-bis ( Hydrosilylation of 3,4-dimethylphenyl) amino] styrene> Toluene 40 ml,
6.0 g (37 mmol) of triethoxysilane and dichloro (h-cycloocta-1,5-diene) platinum (I
I) 0.34 mmol was placed in a three-necked flask, and while stirring at room temperature, a toluene solution of 4- [N, N-bis (3,4-dimethylphenyl) amino] styrene (9.9 g) was added.
ml was added dropwise. After completion of dropping, the mixture was stirred at 70 ° C. for 3 hours, the solvent was removed under reduced pressure, and a pale yellow oily 4-
[N, N-bis (3,4-dimethylphenyl) amino]
-[2- (Triethoxysilyl) ethyl] benzene was obtained. Yield 14.0 g (94.2% yield).

The ionization potential of this compound was measured by a photoelectron analysis method under atmospheric conditions (manufactured by Riken Keiki, surface analyzer AC-1).
Was 5.31 eV.

This compound was applied on a copper substrate by the wire bar coating method and heat-cured at 120 ° C. for 12 hours to form a film of about 5 μm. Next, a translucent gold electrode was formed by vapor deposition.

Pulse width 3 nsec for this sample
-O using a nitrogen laser with a wavelength of 337 nm
When the drift mobility was measured by the f-light method, it was 7 × 10 ⁻⁷ cm ² / Vsec.

Synthesis Example 10 Synthesis of 4- [3- (triethoxysilyl) propyl] triphenylamine <Synthesis of 4-Promotriphenylamine> N-Promosuccinimide 8.0 g (45 mmol), triphenylamine 10 0.0 g (41 mmol) was placed in a 200 ml three-necked flask, and N, N-dimethylformamide 150 was added.
After adding ml, the mixture was stirred overnight at room temperature. Then N,
N-dimethylformamide was removed and the resulting solid was extracted with carbon tetrachloride. Then remove the carbon tetrachloride,
The obtained reaction mixture was recrystallized twice from ethanol,
4-Promotriphenylamine as a white solid was obtained. The yield was 8.2 g (61.7% yield).

<Synthesis of 4-N, N-diphenylaminoallylbenzene> 1.0 g (40 mmol) of magnesium metal was placed in a 300 ml four-necked flask and the atmosphere was replaced with nitrogen. Next, 100 ml of diethyl ether was added and stirring was started. 8.6 g of 4-promotriphenylamine there
Diethyl ether solution 30 in which (27 mmol) was dissolved
ml was slowly added dropwise. When about 3 ml was dropped, reflux started gently. While refluxing, the diethyl ether solution was further added dropwise, and after completion of the addition, the mixture was refluxed for another hour. The Grignard reagent solution obtained as described above was returned to room temperature, and then allyl chloride 2.1 was added.
40 ml of a diethyl ether solution of g (27 mmol) was slowly added dropwise while cooling with ice. After completion of dropping, the reaction mixture was refluxed for 2 hours to mature the reaction. Then 50 ml of water
Was added while cooling with ice to carry out hydrolysis. Next, the ether layer was extracted, washed once with a saturated aqueous solution of sodium hydrogen carbonate and twice with water, and then dried over anhydrous sodium sulfate. After drying, diethyl ether was removed to give 4-N, N as a white solid.
-Diphenylaminoallylbenzene was obtained. Yield 4.9
g (yield 63.2%).

<Hydrosilylation of 4-N, N-diphenylaminoallylbenzene> 40 ml of toluene, 6.0 g (37 mmol) of triethoxysilane and 0.54 mmol of a toluene solution of tris (tetramethyldivinyldisiloxane) diplatinum (0). Was placed in a three-necked flask, and while stirring at room temperature, a solution of 4-N, N-diphenylaminoallylbenzene (9.7 g, 34 mmol) in toluene (20 m).
1 was added dropwise. After completion of dropping, the mixture was stirred at 70 ° C. for 3 hours, the solvent was removed under reduced pressure, and a pale yellow oily 4- [3-
(Triethoxysilyl) propyl] triphenylamine was obtained. Yield 10.7 g (70.1% yield).

The ionization potential of this compound was measured by a photoelectron analysis method under atmospheric conditions (manufactured by Riken Keiki, surface analyzer AC-1).
Was 5.72 eV.

This compound was applied on a copper substrate by a wire bar coating method and heat-cured at 120 ° C. for 12 hours to form a film of about 9 μm. Next, a translucent gold electrode was formed by vapor deposition.

Pulse width 3 nsec for this sample
-O using a nitrogen laser with a wavelength of 337 nm
When the drift mobility was measured by the f-flight method, it was 1.4 × 10 ⁻⁷ cm ² / Vsec.

[Synthesis Example 11] Synthesis of 4- [4- (triethoxysilyl) butyl] triphenylamine <Synthesis of 4-methyltriphenylamine> 4.5 g (27 mmol) of diphenylamine, p-iodotoluene 1
1.0 g (51 mmol), 5.5 g of anhydrous potassium carbonate
(40 mmol) and 1.1 g of copper powder were added to 30 ml of o-dichlorobenzene, and the mixture was heated under reflux with stirring for 7 hours.
After completion of the reaction, the reaction solution was filtered and the filtrate was washed successively with a 35% sodium thiosulfate aqueous solution and saturated saline, and the organic layer was dried over anhydrous sodium sulfate, and then the solvent was removed. The obtained reaction mixture is recrystallized using ethanol. 4-
Methyltriphenylamine was obtained. Yield: 5.7 g (81.4% yield).

<Synthesis of 4-bromomethyltriphenylamine> N-bromosuccinimide 6.9 g (39 mmo)
1), 4-methyltriphenylamine 9.1 g (35 m
(mol) was placed in a 300 ml three-necked flask, 100 ml of carbon tetrachloride was added, and then the mixture was heated under reflux with stirring overnight. After the completion of the reaction, the reaction solution was cooled. Then, the reaction solution was filtered, the solvent was removed, and the obtained reaction mixture was recrystallized using ethanol to obtain 4-bromomethyltriphenylamine. Yield 10.8 g (Yield 91.2)
%).

<4-N, N diphenylaminophenyl-
Synthesis of 1-butene> Magnesium metal (1.0 g, 40 mmol) was placed in a 200 ml four-necked flask and the atmosphere was replaced with nitrogen. Next, 100 ml of diethyl ether was added and stirring was started. Thereto was slowly added dropwise 20 ml of a diethyl ether solution in which 9.1 g (27 mmol) of 4-bromomethyltriphenylamine was dissolved. When about 5 ml was dropped, reflux started gently. While refluxing
Continue adding the diethyl ether solution dropwise, and after the addition is complete,
Reflux for an additional hour. The Grignard reagent solution thus obtained was returned to room temperature, and then a solution of 2.1 g (27 mmol) of allyl chloride in 20 ml of diethyl ether was slowly added dropwise while cooling with ice. After completion of dropping, the reaction mixture was refluxed for 2 hours to mature the reaction. Thereafter, 50 ml of water was added while cooling with ice to effect hydrolysis.
Next, the ether layer was extracted, washed once with a saturated aqueous sodium hydrogen carbonate solution and twice with water, and then dried over anhydrous sodium sulfate. After drying, diethyl ether was removed to obtain 4-N, N-diphenylaminophenyl-1-butene as a white solid. 5.5 g (66.7% yield).

<Hydrosilylation of 4-N, N-diphenylaminophenyl-1-butene> A toluene solution of 40 ml of toluene, 9.9 g (60 mmol) of triethoxysilane and tris (tetramethyldivinyldisiloxane) diplatinum (0). 0.018 mmol was placed in a three-necked flask, and 16.7 g (54.7 mmol) of 4-N, N-diphenylaminophenyl-1-butene was stirred at room temperature.
Of toluene solution was added dropwise. After dropping, 70
After stirring at ℃ for 3 hours, the solvent was removed under reduced pressure to give 4- [4- (triethoxysilyl) butyl] as a pale yellow oil.
Triphenylamine was obtained. Yield 13.9 g ((Yield 8
3.2%).

The ionization potential of this compound was measured by a photoelectron analysis method under atmospheric conditions (manufactured by Riken Keiki, surface analyzer AC-1).
Was 5.69 eV.

This compound was applied onto a copper substrate by the wire bar coating method and heat-cured at 120 ° C. for 12 hours to form a film of about 5 μm. Next, a translucent gold electrode was formed by vapor deposition.

For this sample, the pulse width is 3 nsce.
-O using a nitrogen laser with a wavelength of 337 nm
The drift mobility was measured by the f-flight method and found to be 2 × 10 ⁻⁷ cm ² / Vsec.

[Synthesis Example 12] The resin solution of Synthesis Example 1 was treated with 4-
[2- (Triethoxysilyl) ethyl] triphenylamine (Synthesis Example 5) 70% by weight of the resin solid content was added and mixed. This was applied to a glass plate using a bar coat, and dried at 140 ° C. for 15 hours. Observation with a microscope revealed that a uniform film was formed.

Comparative Synthesis Example 1 Triphenylamine as a hole transporting compound was dissolved in the resin solution of Synthesis Example 1 in an amount of 30% by weight based on the amount of the resin, and mixed and cured in the same manner as in Synthesis Example 12 to form a film. did. The film became cloudy and precipitation of triphenylamine was observed under a microscope.

Comparative Synthesis Example 2 A film was formed in the same manner as in Comparative Synthesis Example 1 except that the resin solution of Synthesis Example 2 was used. Although the opacity of the produced film was lowered, triphenylamine crystals were precipitated by microscopic observation.

[Comparative Synthesis Example 3] 4-obtained in Synthesis Example 5
6 g of trimethylsilane (6 g
0 mmol) was used and the reaction was performed in the same manner as in Synthesis Example 5 to obtain 4- [2- (trimethylsilyl) ethyl] triphenylamine. When a film was produced in the same manner as in Comparative Synthesis Example 1, it was opaque, and 4- [2-
Separation of (trimethylsilyl) ethyl] triphenylamine was observed.

Synthesis Example 13 Synthesis of 4- (N-ethyl-N-phenylamino)-[2- (triethoxysilyl) ethyl] benzene Synthesis of <4- (N-ethyl-N-phenylamino) benzaldehyde > To a three-necked flask, 82 g of diphenylethylamine and 35.5 ml of DMF were added, and 84.4 ml of phosphorus oxychloride was added dropwise with stirring while cooling with ice water. After the addition was completed, the temperature was raised to 95 ° C. and the reaction was carried out for 5 hours. It was Then, the precipitate was collected by filtration and the mixed solution of ethanol / water (1: 1) was washed to obtain 4- (N-phenylamino) ethylbenzaldehyde. Yield 62 g.

<Synthesis of 4- (N-ethyl-N-phenylamino) styrene> Sodium hydride 14.6 g,
700 ml of 1,2-dimethoxyethane was placed in a three-necked flask, and 130.8 g of trimethylphosphonium bromide was added with stirring at room temperature. Next, after adding one drop of absolute ethanol, the temperature was raised to 70 ° C. and the reaction was carried out for 5 hours. The reaction solution was filtered, and the filtrate and the ether extract of the precipitate were combined and washed with water. Next, the ether solution was dehydrated with calcium chloride, and the ether was removed to obtain a reaction mixture. This was recrystallized from ethanol to obtain acicular, pale yellow crystals. Yield 62.4 g.

<Hydrosilylation of 4- (N-ethyl-N-phenylamino) styrene> Toluene 40 ml, triethoxysilane 9.9 g (60 mmol) and tris (tetramethyldivinyldisiloxane) diplatinum (0)
Toluene solution 0.018 mmol was placed in a three-necked flask, and while stirring at room temperature, 20 ml of a toluene solution of 7.6 g of 4- (N-ethyl-N-phenylamino) styrene.
Was dripped. After completion of the dropwise addition, the mixture was stirred at 70 ° C. for 3 hours, the solvent was removed under reduced pressure, and a pale yellow oily 4- (N-
Ethyl-N-phenylamino)-[2- (triethoxysilyl) ethyl] benzene was obtained. Yield 7.8g.

The ionization potential of this compound was measured by a photoelectron analysis method under air (manufactured by Riken Keiki, surface analyzer AC-1).
Was 6.3 eV.

This compound was applied on a copper substrate by a wire bar coating method, and thermally cured at 120 ° C. for 12 hours to form a film of about 5 μm. Next, a translucent gold electrode was formed by vapor deposition.

Pulse width 3 nsec for this sample
-O using a nitrogen laser with a wavelength of 337 nm
When the drift mobility was measured by the f-flight method, it was 2 × 10 ⁻⁸ cm ² / Vsec.

Example 1 Alcohol-soluble copolymer nylon (trade name Amilan CM-8000, manufactured by mirror-finishing) was placed on an aluminum cylinder having an outer diameter of 80 mm.
A solution obtained by dissolving 5 parts by weight of Toray Industries, Inc. in 95 parts by weight of methanol was applied by a dip coating method. 80 ℃
And dried for 10 minutes to form an undercoat layer having a film thickness of 1 μm.

Next, as a charge generation layer dispersion liquid, 5 parts by weight of the following bisazo pigment was added to a solution in which 95 parts by weight of cyclohexanone and 2 parts by weight of polyvinylbenzal (having a degree of benzalization of 75% or more) were dissolved. Time dispersed.

This dispersion was applied onto the previously formed undercoat layer by a dip coating method so that the film thickness after drying would be 0.2 μm.

[0144]

[Outside 14]

Next, 5 parts by weight of a triarylamine compound having the following structural formula and 5 parts by weight of a polycarbonate resin (trade name Z-200, manufactured by Mitsubishi Gas Chemical Co., Inc.) were dissolved in 70 parts by weight of chlorobenzene to form a charge transport layer. A solution for use in which 0.3 part by weight of silicone resin fine particles having an average particle size of 2 μm was added was dried on the charge generation layer by a dip coating method and then applied to a film thickness of 10 μm.

[0146]

[Outside 15]

Next, 200 parts by weight of toluene was added to 100 parts by weight of the curable composition of Synthesis Example 1 and 4-synthesized in Synthesis Example 8.
[N, N-bis (3,4-dimethylphenyl) amino]
-[2- (triethoxysilyl) ethyl] benzene 40
The curable composition containing parts by weight was applied by a spray coating method.

By drying at 140 ° C. for 4 hours and thermosetting, a transparent and uniform surface protective layer having a thickness of 2 μm was formed.

When this electrophotographic photosensitive member was charged to -700 V and the electrophotographic characteristics were measured using light having a wavelength of 680 nm, E1 / 2 (exposure amount necessary for reducing the charging potential to -350 V) was found. The residual potential was 1.2 μJ / cm ² , and the residual potential was −26 V, which was excellent.

This electrophotographic photosensitive member was mounted on a Canon digital full-color copying machine CLC-500 for 63.5 in the sub-scanning direction.
irradiation spot diameter of 1 μm and 20 μm in the main scanning direction (1 / e
² ) Initial charge-5 using an evaluation machine modified to
When the image was evaluated by setting it to 00V, the initial and 1
After the endurance test of 0,000 sheets, there was no charge injection such as black spots and interference fringes, the amount of wear on the photoconductor was as small as 0.8 μm, and image output with excellent uniformity was obtained, and the gradation reproducibility was 2 at 400 dpi.
The tone was 56, which was extremely good.

Comparative Synthesis Example 4 Resin Solution 10 of Synthesis Example 4
The triarylamine compound used in Example 1 was dissolved in 0 part by weight in an amount of 30% by weight based on the amount of the resin, and mixed and cured in the same manner as in Synthesis Example 12 to form a film. The film became cloudy and precipitation of triphenylamine was observed under a microscope.

[Comparative Example 1] An image of an electrophotographic photosensitive member prepared in the same manner as in Example 1 except that the protective layer was not coated was subjected to image evaluation. After a durability test of 20,000 sheets, a large amount of black spots and the like were found. A good image could not be obtained due to the occurrence of the above phenomenon. The amount of abrasion of the photoconductor was 20,000 sheets and was extremely large at 5 μm.

Example 2 On an aluminum cylinder having an outer diameter of 30 mm obtained by drawing, 167 parts by weight of a phenol resin (trade name Praiophen, manufactured by Dainippon Ink and Chemicals, Inc.) was added to 100 parts by weight of methyl cellosolve. Conductive barium sulfate ultrafine particles (1
A dispersion of 200 parts by weight of a secondary particle size of 50 nm) and 3 parts by weight of silicone resin particles having an average particle size of 2 μm was applied by a dip coating method to form a conductive layer having a thickness of 15 μm after drying.

Alcohol-soluble copolymer nylon (trade name: Amilan CM-8000, Toray Industries, Inc.) was formed on the conductive layer.
5 parts by weight dissolved in 95 parts by weight of methanol was applied by a dip coating method. It was dried at 80 ° C. for 10 minutes to form an undercoat layer having a film thickness of 1 μm.

Next, CuKα was used as the dispersion for the charge generation layer.
5 parts by weight of oxytitanium phthalocyanine pigment having strong peaks at 9.0 °, 14.2 °, 23.9 ° and 27.1 ° of the black angle (2θ ± 0.2 °) in characteristic X-ray diffraction was added to cyclohexanone 95. 2 parts by weight of polyvinylbenzal (having a degree of benzal of 75% or more) was dissolved in parts by weight, and the mixture was dispersed in a sand mill for 2 hours.

This dispersion was applied onto the previously formed undercoat layer by a dip coating method so that the film thickness after drying would be 0.2 μm.

Next, 55 parts by weight of the organosilicon-modified triarylamine compound synthesized in Synthesis Example 9 and 100 parts by weight of the silicone-based thermosetting resin of Synthesis Example 3 were added to 100 parts by weight of toluene and dissolved to prepare the above charge generation layer. It was coated on the above by the dip coating method. Dried at 120 ° C for 5 hours,
It was heat-cured to form a transparent and uniform charge transport layer having a film thickness of 10 μm.

The pencil hardness is 5H and the contact angle of water is 10
5 degrees.

This electrophotographic photosensitive member was charged to -700 V and the electrophotographic characteristics were measured using light having a wavelength of 680 nm. As a result, E1 / 2 (exposure amount necessary for reducing the charging potential to -350 V) was obtained. The residual potential was 0.2 μJ / cm ² , and the residual potential was −32 V, which was excellent.

This electrophotographic photosensitive member was initially used by using a modified laser beam printer LBP-8IV manufactured by Canon Inc. (irradiation spot (1 / e ² ) was modified to 63.5 μm in the sub-scanning direction and 20 μm in the main scanning direction). When the image was evaluated by setting the charge to -500V, the abrasion loss of the photoreceptor after the 4000 sheets durability test was extremely small, 0.1 μm or less, and the contact angle of water after the durability test was 100 degrees, which was good. Was not deteriorated, and the reproducibility of one pixel in the highlight portion in the input signal equivalent to 600 dpi was sufficient.

Comparative Example 2 5 parts by weight of the triarylamine compound used in Example 1 and 5 parts by weight of a polycarbonate resin (trade name Z-200, manufactured by Mitsubishi Gas Chemical Co., Inc.) were dissolved in 70 parts by weight of chlorobenzene. The liquid for the charge transport layer was applied onto the charge generation layer of Example 2 by a dip coating method to form a charge transport layer having a film thickness after drying of 10 μm. When the obtained electrophotographic photosensitive member was evaluated in the same manner as in Example 2, interference fringes and black spots were observed after the durability test of 4000 sheets, and the abrasion amount was 1.8 μm.
Since the contact angle of water is as large as 72 m and the contact angle of water is as small as 72 degrees, it is defective, and the reproduction of one pixel in the highlight portion at 600 dpi is insufficient and uneven.

Example 3 On an aluminum cylinder similar to that of Example 2, 167 parts by weight of a phenol resin (trade name Praiophen, manufactured by Dainippon Ink and Chemicals, Inc.) was dissolved in 100 parts by weight of methyl cellosolve. A dispersion of 200 parts by weight of conductive barium sulfate ultrafine particles (primary particle size 50 nm) was applied by a dip coating method so that the film thickness after drying would be 10 μm. An undercoat layer having a film thickness of 1 μm was formed on the conductive support in the same manner as in Example 2.
And a charge generation layer having a thickness of 0.2 μm was formed.

Next, 40 parts by weight of the organosilicon-modified triarylamine compound synthesized in Synthesis Example 8 and 100 parts by weight of the silicone-based thermosetting resin of Synthesis Example 2 were added to 100 parts by weight of toluene and dissolved, and the average particle size was further 3 μm. SiO
₂ 0.5 parts by weight of fine particles were added to the above charge generation layer and applied by dip coating. 120 ° C
Was dried for 5 hours and heat-cured to form a charge transport layer having a film thickness of 10 μm.

When observed under a microscope, it was transparent and uniform except for the SiO ₂ particles.

The pencil hardness was 4H and the contact angle of water was 11
It was 0 degrees.

This electrophotographic photosensitive member was charged to -700 V, and the electrophotographic characteristics were measured using light having a wavelength of 680 nm. As a result, E1 / 2 (exposure amount necessary for reducing the charging potential to -350 V) was obtained. The residual potential was 0.23 μJ / cm ² , and the residual potential was 31 V, which were favorable.

The electrophotographic photoreceptor was set to an initial charge of -500 V using the same laser beam printer as in Example 2 and image evaluation was carried out. As a result, the abrasion loss of the photoreceptor after 10,000 durability tests was found. The contact angle of water is as small as 0.2 μm or less, the contact angle of water is as good as 102 degrees, and there is no image deterioration due to charge injection such as black spots and interference fringes, and 1 pixel reproducibility of the highlight part in the input signal equivalent to 600 dpi. Was enough.

Example 4 Similar to Example 1, a charge generating layer was formed.

Then, 0.1 part by weight of silicone resin fine particles having an average particle size of 2 μm was added to the liquid for the charge transport layer used in Example 1 and dried on the above charge generating layer by a dip coating method. It was applied to a film thickness of 9 μm.

Next, as a surface protection layer, 200 parts by weight of toluene in 100 parts by weight of the resin solution of Synthesis Example 4 and 4- [N, N-bis (3,4-dimethylphenyl) amino] -synthesized in Synthesis Example 8 were used. [2- (triethoxysilyl) ethyl]
A curable composition containing 40 parts by weight of benzene was applied by a spray coating method.

By drying at 140 ° C. for 4 hours and thermosetting, a transparent and uniform surface protective layer having a thickness of 3 μm was formed. The pencil hardness was 2H and the contact angle of water was 115 degrees.

When the electrophotographic characteristics of this electrophotographic photosensitive member were evaluated in the same manner as in Example 1, E1 / 2 = 0.70.
μJ / cm ² , and the residual potential was good at -35V.

Using the same digital full-color copying machine as in Example 1, the present electrophotographic photosensitive member was set to an initial charge of -400 V and image evaluation was carried out. As a result, the abrasion loss after 10,000 sheets of durability test was 0. It is extremely small at 13 μm, and the contact angle of water is 1
It was 09 degrees, and an image with excellent reproducibility in the highlight portion and the high density portion was obtained.

[Embodiment 5] A charge generation layer was formed in the same manner as in Embodiment 2.

Next, 60 parts by weight of the organosilicon-modified triarylamine compound synthesized in Synthesis Example 13 and 100 parts by weight of the silicone thermosetting resin of Synthesis Example 3 were added to 100 parts of toluene.
What was added in addition to the weight part and melt | dissolved was apply | coated by the dip coating method on the said charge generation layer. The photoconductor of the present invention having a charge transport layer having a thickness of 10 μm was prepared by drying at 120 ° C. for 5 hours and heat curing.

The pencil hardness is 5H and the contact angle of water is 10.
7 degrees.

When the electrophotographic characteristics were measured in the same manner as in Example 2, E1 / 2 was 0.20 μJ / cm ² , and the residual potential was −45V.

Using the same laser beam printer as in Example 2, the present electrophotographic photosensitive member was set to an initial charge of −500 V and image evaluation was carried out. As a result, the abrasion loss of the photosensitive member after 10,000 sheets of durability test was found. It is extremely small at 0.28 μm, the contact angle of water is as good as 98 degrees, there is no image deterioration due to charge injection such as black spots and interference fringes, and the 1-pixel reproducibility of the highlight part in an input signal equivalent to 600 dpi is sufficient. Met.

[0179]

As described above, according to the present invention, there is no light scattering or bleeding, the electrophotographic photosensitive member is uniform and has both low surface energy and mechanical and electrical durability, and the electrophotographic photosensitive member. A process cartridge having a body and an image forming apparatus can be provided.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a layer structure of an electrophotographic photosensitive member of the present invention.

FIG. 2 is a diagram showing an example of a layer structure of an electrophotographic photosensitive member of the present invention.

FIG. 3 is a diagram showing a relationship between a light intensity distribution, a spot diameter, and a product of a light spot area and a thickness of a photosensitive layer.

FIG. 4 is a diagram illustrating a schematic configuration of a first example of the image forming apparatus of the present invention.

FIG. 5 is a diagram showing a schematic configuration of a second example of the image forming apparatus of the invention.

FIG. 6 4- [2- (triethoxysilyl) of Example 5
3 is an H-NMR spectrum of ethyl] triphenylamine.

FIG. 7 is an H-NMR spectrum of 4- [N, N-bis (3,4-dimethylphenyl) amino]-[2- (triethoxysilyl) ethyl] benzene of Example 8.

FIG. 8 is a C-NMR spectrum of 4- [N, N-bis (3,4-dimethylphenyl) amino]-[2- (triethoxysilyl) ethyl] benzene of Example 8.

Claims (13)

[Claims] 1. An electrophotographic photoreceptor having a photosensitive layer on a support, wherein the surface layer of the electrophotographic photoreceptor is a curable organosilicon polymer and the following formula (1) (A represents a hole transporting group, Q represents a hydrolyzable group or a hydroxyl group, R ² represents a substituted or unsubstituted monovalent hydrocarbon group, and R ³ represents a substituted or unsubstituted alkylene group or arylene. Represents a group, m represents an integer of 1 to 3, and 1
Represents a positive integer. ) An electrophotographic photoreceptor containing a resin obtained by curing an organosilicon-modified hole transporting compound represented by 2. R ² is a monovalent hydrocarbon group having 1 to 15 carbon atoms or a halogen-substituted monovalent hydrocarbon group, and R ³ is The electrophotographic photosensitive member according to claim 1, wherein n is an integer of 1 to 18 and 1 is an integer of 1 to 5. 3. The electrophotographic photoreceptor according to claim ^{1, wherein} Q is —OR ¹ (R ¹ represents an alkyl group or an alkoxyalkyl group). 4. The electrophotographic photosensitive member according to claim 3, wherein R ¹ has 1 to 6 carbon atoms. 5. A is the following formula (2): (R ⁴ , R ⁵ and R ⁶ are organic groups, at least one of which represents an aromatic hydrocarbon ring group or a heterocyclic group, and R ⁴ , R ⁵ and R ⁶ are the same or different. 5. The electrophotographic photosensitive member according to claim 1, wherein 6. A curable organosilicon polymer is represented by the following formula (3) R ⁷ _r SiO _{(4-rs) / 2} (OR ⁸ ) _s (3) (R ⁷ is a linear or branched alkyl group, The electrophotographic photosensitive member according to claim 1, wherein R ⁸ represents an alkenyl group or an aryl group, R ⁸ represents a hydrogen atom or an alkyl group, and r and s represent a molar ratio. 7. The electrophotographic photoreceptor according to claim 6, wherein r is 0.5 to 1.5 on average, and s is 0.01 to 1.5 on average. 8. The modified organosilicon hole-transporting compound.
The electrophotographic photosensitive member according to any one of claims 1 to 7, which has an ionization potential of 5 to 6.2 eV. 9. The method according to claim 1, wherein the modified organosilicon hole transporting compound is 1 ×
The electrophotographic photosensitive member according to any one of claims 1 to 8 having 10 ^-7 cm ² / Vsec or more drift mobility. 10. A process cartridge which integrally supports an electrophotographic photosensitive member and at least one unit selected from the group consisting of a charging unit, a developing unit and a cleaning unit, and which is detachable from the main body of the image forming apparatus. The photographic photoreceptor is an electrophotographic photoreceptor having a photosensitive layer on a support, and the surface layer of the electrophotographic photoreceptor is a curable organosilicon polymer and the following formula (1) (A represents a hole transporting group, Q represents a hydrolyzable group or a hydroxyl group, R ² represents a substituted or unsubstituted monovalent hydrocarbon group, and R ³ represents a substituted or unsubstituted alkylene group or arylene. Represents a group, m represents an integer of 1 to 3, and 1
Represents a positive integer. A process cartridge containing a resin obtained by curing the modified organosilicon hole transporting compound represented by the formula (1). 11. R ² is a monovalent hydrocarbon group having 1 to 15 carbon atoms or a halogen-substituted monovalent hydrocarbon group, and R ³ is The process cartridge according to claim 10, wherein the process cartridge is represented by (n is an integer of 1 to 18), and l is an integer of 1 to 5. 12. An image forming apparatus having an electrophotographic photosensitive member, a charging unit, an exposing unit, a developing unit and a transferring unit, wherein the electrophotographic photosensitive member has a photosensitive layer on a support, The surface layer of the electrophotographic photoreceptor is a curable organosilicon polymer and the following formula (1) (A represents a hole transporting group, Q represents a hydrolyzable group or a hydroxyl group, R ² represents a substituted or unsubstituted monovalent hydrocarbon group, and R ³ represents a substituted or unsubstituted alkylene group or arylene. Represents a group, m represents an integer of 1 to 3, and 1
Represents a positive integer. An image forming apparatus comprising a resin obtained by curing the modified organosilicon hole transporting compound represented by the formula (1). 13. R ² is a monovalent hydrocarbon group having 1 to 15 carbon atoms or a halogen-substituted monovalent hydrocarbon group, and R ³ is The image forming apparatus according to claim 12, wherein (n is an integer of 1 to 18), and l is an integer of 1 to 5.