JP2000338703A - Electrophotographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an electrophotographic device which is superior in transfer efficiency of a toner from the surface of a photoreceptor to a intermediate transfer body. SOLUTION: The electrophotographic device is equipped with a latent image forming means 2, 3 to form an electrostatic latent image on an electrophotographic photoreceptor 1 having at least a photosensitive layer and a surface protective layer sequentially formed on a conductive supporting body, a developing means 4 to develop the electrostatic latent image to dorm a toner image, a first transfer means 7 to transfer the toner image to an intermediate transfer body, and a second transfer means 9 to transfer the toner image on the intermediate transfer body to a transfer material. The surface protective layer of the electrophotographic photoreceptor 1 consists of at least a polysiloxane and a silyl group-containing vinyl resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electrophotographic apparatus, and more particularly, to an electrophotographic apparatus having at least an electrophotographic photosensitive member and an intermediate transfer member.

[0002]

2. Description of the Related Art Recently, a color image forming apparatus and a multi-color image forming apparatus for sequentially transferring a plurality of component color images of color image information and multi-color image information and outputting an image formed by combining and reproducing the color image and the multi-color image are disclosed. 2. Description of the Related Art The use of an intermediate transfer member in an image forming apparatus or an electrophotographic apparatus such as an image forming apparatus having a color image forming function or a multicolor image forming function has been actively performed. This is because, by using the intermediate transfer member, the superposition of the respective component color images is appropriately secured, and an image free from deviation (color deviation) can be obtained.

In the photoreceptor used in such an electrophotographic apparatus, the surface of the photosensitive layer is protected from the viewpoint of preventing abrasion of the photosensitive layer by a cleaning member or the like and preventing injection of surface charges into the photosensitive layer. It is known to provide layers. In addition, as a photosensitive layer material, inexpensive, mass productivity,
In general, an organic photosensitive material is used as a material from the viewpoint of non-polluting properties.

It is known that silica formed by repeating a siloxane bond (Si—O—Si bond) three-dimensionally is preferable as a material for forming the surface protective layer from the viewpoint of durability (for example, Japanese Patent Publication No. HEI-5-202). -46940 and JP-A-53-39131). In addition, a polymer such as an acrylic resin, urethane elastomer or polyamide is mixed with an organosilane as a silica raw material, and the mixed solution (surface protection solution) is applied on the photosensitive layer and cured to form a surface protection layer. Have been reported (for example, JP-A-3-141365, JP-A-1-293660).
JP, JP-A-3-135575, JP-A-5-3
41551, JP-A-3-135577, etc.).

However, when such a conventional photoreceptor having a surface protective layer is used in an electrophotographic apparatus using the above-described intermediate transfer member, a toner image developed on the surface of the photoreceptor is transferred to the intermediate transfer member. At the time of transfer, there has been a problem that the transfer is not performed smoothly, the toner remains on the surface of the photoreceptor, and transfer efficiency is significantly reduced.

When the surface protective layer of the above photoreceptor is made only of silica, cracks (cracks) are generated on the surface of the protective layer, adhesion to the photosensitive layer is deteriorated, The problem was that the electrostatic properties of the layer were degraded. Further, when the surface protective layer is made of the above-mentioned polymer and silica raw material, the resulting surface protective layer has poor denseness and low surface hardness as a film, and thus has a problem in durability, particularly abrasion. . Further, when the thickness of the surface protective layer is increased to about 5 μm, the sensitivity is low, the residual potential is high, and there has been a problem that fogging or the like occurs during durability.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide an electrophotographic apparatus which is excellent in toner transfer efficiency from the surface of a photosensitive member to an intermediate transfer member. .

The present invention also provides an electrophotographic photoreceptor and an intermediate transfer member which are excellent in electrostatic properties such as adhesion, durability and sensitivity between the surface protective layer and the photosensitive layer and which do not cause problems such as cracks. An object of the present invention is to provide an electrophotographic apparatus.

[0009]

According to the present invention, there is provided a latent image forming means for forming an electrostatic latent image on an electrophotographic photosensitive member having at least a photosensitive layer and a surface protective layer sequentially provided on a conductive support. Developing means for developing the electrostatic latent image to form a toner image; first transfer means for transferring the toner image to an intermediate transfer member; and second transfer means for transferring the toner image on the intermediate transfer member to a transfer material. The present invention relates to an electrophotographic apparatus provided with the electrophotographic apparatus, wherein the surface protective layer of the electrophotographic photoreceptor comprises at least polysiloxane and a silyl group-containing vinyl resin.

[0010] The surface protective layer of the electrophotographic photoreceptor used in the electrophotographic apparatus of the present invention comprises at least polysiloxane and a silyl group-containing vinyl resin, preferably at least polysiloxane and a silyl group-containing vinyl resin. Are combined. That is, the surface protective layer of the present invention is a mixture of polysiloxane and a silyl group-containing vinyl resin, preferably, a polysiloxane and a silyl group in the silyl group-containing vinyl resin are chemically bonded. The silyl group of the silyl group-containing vinyl resin is incorporated into the structure of the polysiloxane in which the bond is repeated three-dimensionally.

The polysiloxane in the surface protective layer of the photoreceptor has a structure in which a plurality of siloxane bonds are connected, and preferably has a structure in which the siloxane bonds are three-dimensionally repeated. Above all, polysiloxane is represented by the following general formula (I); (R ¹ ) _n Si (OR ² ) _4-n (I) (wherein, R ¹ is an organic group having 1 to 8 carbon atoms, and R ² is a carbon atom having 1 carbon atom. ~
5 represents an alkyl group or an acyl group having 1 to 4 carbon atoms,
n is an integer of 0 to 2. ) (Hereinafter referred to as organosilane (I)) preferably has a polycondensed structure. In the general formula (I),
Examples of the organic group having 1 to 8 carbon atoms for R ¹ include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, and an n-
Butyl group, i-butyl group, sec-butyl group, t-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group and other alkyl groups, γ-chloropropyl group, γ-bromopropyl group, 3,3,3-trifluoropropyl group, γ-glycidoxypropyl group, γ-
(Meth) acryloxypropyl group, γ-mercaptopropyl group, γ-aminopropyl group, γ-dimethylaminopropyl group, 2- (3,4-epoxycyclohexyl)
Examples include an ethyl group, a vinyl group, and a phenyl group. Examples of the alkyl group having 1 to 5 carbon atoms of R ² include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, a sec-butyl group, and a t-butyl group. -Butyl group, n-pentyl group and the like, and examples of the acyl group having 1 to 4 carbon atoms include an acetyl group, a propionyl group and a butyryl group. In the present specification, “(meth) acryl” means “acryl” or “methacryl”, and, for example, methyl (meth) acrylate includes methyl acrylate and methyl methacrylate. .

Specific examples of such an organosilane (I) include tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane. Silane, n-propyltriethoxysilane, i-propyltrimethoxysilane, i-propyltriethoxysilane, γ-chloropropyltrimethoxysilane, γ-chloropropyltriethoxysilane, 3,3,3-trifluoropropyltrimethoxy Silane, 3,3,3-trifluoropropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane,
γ-methacryloxypropyltrimethoxysilane, γ
-Methacryloxypropyltriethoxysilane, γ-
Mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, 3,4-epoxycyclohexylethyltrimethoxysilane, 3,4-epoxycyclohexylethyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, phenyltrimethoxysilane , Phenyltriethoxysilane,
Dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, di-n-propyldimethoxysilane, di-n-propyldiethoxysilane, di-i-propyldimethoxysilane, di-i-propyldiethoxy Alkoxysilanes such as silane, divinyldimethoxysilane, divinyldiethoxysilane, diphenyldimethoxysilane, and diphenyldiethoxysilane; tetraacetoxysilane, methyltriacetoxysilane, ethyltriacetoxysilane, dimethyldiacetoxysilane, diethyldiacetoxysilane, and the like Acyloxysilanes and the like, preferably methyltrimethoxysilane, methyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, tetramethy Shishiran, tetraethoxysilane. The organosilane (I) can be used alone or in combination of two or more.

The silyl group-containing vinyl resin constituting the surface protective layer is not particularly limited as long as it is a vinyl resin having a silyl group. The vinyl resin may be a known resin.
Although the content of the silyl group is not particularly limited, the content of the silyl group is 1 to 40 per 100 monomers constituting the vinyl resin.
And preferably 2 to 25. If the content of the silyl group is too small, the adhesion and durability between the surface protective layer of the photoreceptor and the photosensitive layer deteriorate. If too large, cracks occur in the surface protective layer.

The method for producing the silyl group-containing vinyl resin is not particularly limited. For example, it may be obtained by once introducing a silyl group after obtaining a vinyl resin, or by polymerizing a vinyl compound having a silyl group with various vinyl compounds. Specifically, the silyl group-containing vinyl resin may be produced, for example, by reacting (a) a hydroxysilane compound with a vinyl resin having a carbon-carbon double bond, and (b) the following general formula (II) );

Embedded image Wherein R ³ is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aralkyl group having 1 to 10 carbon atoms, R ⁴ is an organic group having a polymerizable double bond, X is a halogen atom, an alkoxy group, an acyloxy group. And n represents an integer of 1 to 3), and a vinyl compound may be polymerized with a silane compound represented by the formula:

Here, examples of the hydroxysilane compound used in the production method shown in (a) above include halogenated silanes such as methyldichlorosilane, trichlorosilane and phenyldichlorosilane; methyldiethoxysilane; Alkoxysilanes such as methyldimethoxysilane, phenyldimethoxysilane, trimethoxysilane and triethoxysilane; methyldiacetoxysilane;
Acetoxysilanes such as phenyldiacetoxysilane and triacetoxysilane; methyldiaminoxysilane,
Examples include aminosilanes such as triaminoxysilane, dimethylaminoxysilane, and triaminosilane. These hydroxysilane compounds can be used alone or in combination of two or more.

The vinyl resin used in the production method shown in (a) is not particularly limited, except for the vinyl resin containing a hydroxyl group. For example, methyl (meth) acrylate, (meth) acryl Ethyl acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate,
(Meth) acrylic acid esters such as cyclohexyl (meth) acrylate; (meth) acrylic acid, itaconic acid,
Carboxylic acids such as fumaric acid and acid anhydrides such as maleic anhydride; epoxy compounds such as glycidyl (meth) acrylate; amino compounds such as diethylaminoethyl (meth) acrylate and aminoethyl vinyl ether;
(Meth) acrylamide, itaconic diamide, α-ethylacrylamide, crotonamide, fumaric diamide, maleic diamide, N-butoxymethyl (meth)
Amide compounds such as acrylamide; vinyl resins obtained by polymerizing or copolymerizing one or more vinyl compounds selected from the group consisting of acrylonitrile, styrene, α-methylstyrene, vinyl chloride, vinyl acetate, vinyl propionate and the like are preferable. .

On the other hand, in the manufacturing method shown in (b)
Silane compounds include silyl groups, especially hydrolyzable
Having a silyl group having the following various vinyl compounds and
The compound is not particularly limited as long as it is a polymerizable compound.
H_Two= CHSi (CH_Three) (OCH_Three)_Two, CH_Two= CHS
i (OCH_Three)_Three, CH_Two= CHSi (CH_Three) Cl_Two, C
H_Two= CHSiCl_Three, CH_Two= CHCOO (CH_Two)_TwoS
i (CH_Three) (OCH_Three)_Two, CH_Two= CHCOO (C
H_Two)_TwoSi (OCH_Three)_Three, CH_Two= CHCOO (CH_Two)
_ThreeSi (CH_Three) (OCH_Three)_Two, CH_Two= CHCOO (C
H_Two)_ThreeSi (OCH_Three) _Three, CH_Two= CHCOO (CH_Two)
_TwoSi (CH_Three) Cl_Two, CH_Two= CHCOO (CH_Two)_TwoS
iCl_Three, CH_Two= CHCOO (CH_Two)_ThreeSi (CH_Three)
Cl_Two, CH_Two= CHCOO (CH_Two)_ThreeSiCl_Three, CH_Two
= C (CH_Three) COO (CH_Two)_TwoSi (CH_Three) (OCH
_Three)_Two, CH_Two= C (CH_Three) COO (CH_Two)_TwoSi (OC
H_Three)_Three, CH_Two= C (CH_Three) COO (CH_Two)_ThreeSi (C
H_Three) (OCH_Three)_Two, CH_Two= C (CH_Three) COO (C
H_Two)_ThreeSi (OCH_Three)_Three, CH_Two= C (CH_Three) COO
(CH_Two)_TwoSi (CH_Three) Cl_Two, CH_Two= C (CH_Three) C
OO (CH_Two)_TwoSiCl_Three, CH_Two= C (CH_Three) COO
(CH_Two)_ThreeSi (CH_Three) Cl_Two, CH_Two= C (CH_Three) C
OO (CH_Two)_ThreeSiCl_Three,

[0018]

Embedded image And the like. These silane compounds can be used alone or in combination of two or more.

As the various vinyl compounds used in the production method shown in (b), the vinyl compounds exemplified in the description of the vinyl resin used in the production method (a) can be used. However, besides these examples,
Vinyl compounds containing a hydroxyl group, for example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxyvinyl ether, N-methylolacrylamide, and the like can be given. These vinyl compounds can be used alone or in combination of two or more.

The polymerization degree of the silyl group-containing vinyl resin used in the present invention is not particularly limited, but is preferably from 100 to 500.

In the surface protective layer of the photoreceptor, the mixing ratio of the above polysiloxane to the silyl group-containing vinyl resin (polysiloxane / silyl group-containing vinyl resin) is 20 by weight.
/ 80-80 / 20, preferably 30 / 70-70 / 3
Desirably, it is 0. If the blending ratio of the polysiloxane is small, the film strength decreases, while if it is too large, the adhesiveness to the photosensitive layer deteriorates. In the case where the polysiloxane and the silyl group-containing vinyl resin are chemically bonded in the protective layer, the mixing ratio of the polysiloxane portion and the silyl group-containing vinyl resin portion may be within the above range. .

The thickness of the surface protective layer is not particularly limited.
From the viewpoints of electrostatic characteristics such as sensitivity and residual potential, and adhesion and durability to the photosensitive layer, 0.03 to 5 μm, preferably 0.1 to 5 μm.
It is desirable that the thickness be 1 to 3 μm.

The above-mentioned surface protective layer may contain a fluorine-containing silicone compound. By blending the fluorine-containing silicone compound, the surface energy of the surface protective layer can be reduced and higher transfer efficiency can be achieved. The fluorinated silicone compound is not particularly limited as long as it is a silicone compound having a fluorinated alkyl group. For example, the following general formula (III):

Embedded image(Wherein X is a fluorinated alkyl group having 1 to 10 carbon atoms, R
^Five, R⁶, R⁷, R⁸, R⁹Each independently has 1 to 1 carbon atoms
An alkyl group of 4 and n represents an integer of 1 or more. )
Compounds. In the above general formula (III), carbon
Examples of the fluorine-containing alkyl group of Formulas 1 to 10 include, for example, C
F_Three, CF_ThreeCH_Two, CF_ThreeCF_TwoCH_Two, CF _ThreeC_TwoH_Four, C
F_Three(CF_Two)_TwoC_TwoH_FourAnd the like having 1 to 4 carbon atoms.
As the alkyl group, a methyl group, an ethyl group, n-propyl
Group, i-propyl group, n-butyl group, i-butyl group, s
ec-butyl group, t-butyl group and the like. Also,
n is usually an integer of 2 to 10.

From the viewpoint of the mechanical strength of the surface protective layer to be obtained, the amount of the fluorine-containing silicone compound is not more than 50% by weight, preferably not more than 5% by weight, based on the sum of the polysiloxane and the silyl group-containing vinyl resin. 30% by weight is suitable.

The surface protective layer may contain fine conductive metal particles. By blending the conductive metal fine particles, the electrostatic characteristics of the photoreceptor can be further improved, that is, good sensitivity can be secured and the residual potential can be reduced. As the conductive metal fine particles, for example,
Examples thereof include metal antimony salts that are conductive colloidal fine particles, and alumina sol that is colloidal fine particles.

The size of the conductive metal fine particles may be 0.01 μm as the average volume particle size or the maximum length of the particle projected image.
０．３0.3 μm, preferably 0.01-0.1 μm. The compounding amount is 50% by weight or less, preferably 5 to 5% by weight, based on the sum of the polysiloxane and the silyl group-containing vinyl resin from the viewpoint of preventing noise on the copied image.
30% by weight is suitable.

The surface protective layer may contain an inorganic filler and organic fine particles. By blending these, the hardness and roughness of the surface can be easily adjusted. Examples of the inorganic filler include metal oxides such as silica, titanium oxide, zinc oxide, calcium oxide, aluminum oxide and zirconium oxide, metal sulfides such as barium sulfate and calcium sulfate, and metal nitrides such as nitrogen silicon and nitrogen aluminum. Particularly preferred are silica and titanium oxide. The inorganic filler may be used alone or in combination of two or more. Examples of the organic fine particles include a fluorine resin, a silicone resin, an acrylic resin, and an olefin resin. Particularly preferable examples include a fluorine resin such as polytetrafluoroethylene and polyvinyldene fluoride and an olefin resin such as polyethylene and polypropylene. . One or two organic fine particles
You may mix and use more than one kind.

The size of the inorganic filler and the organic fine particles is 0.01 to 1.0 μm, preferably 0.01 to 1.0 μm, as the average volume particle size or the maximum length of the projected image of the particles.
Desirably, it is 3 μm. The amount of the inorganic filler is 50% by weight or less, preferably 5% by weight, based on the sum of the polysiloxane and the silyl group-containing vinyl resin from the viewpoint of the sensitivity of the photoreceptor and the electrostatic properties such as residual potential during printing. ~ 30
% By weight. The amount of organic fine particles
From the viewpoint of the sensitivity of the photoreceptor and electrostatic characteristics such as residual potential during printing, the amount of the polysiloxane and the silyl group-containing vinyl resin is 1 to 150% by weight, preferably 5 to 100% by weight.
% By weight.

The surface protective layer of the photoreceptor in the electrophotographic apparatus of the present invention may be formed by any method as long as the above-mentioned surface protective layer is formed. For example, the surface protective layer may be obtained by applying a surface protective solution containing at least the above-mentioned polysiloxane and a silyl group-containing vinyl resin on the photosensitive layer and drying the photosensitive layer, or may be formed by drying at least the above-mentioned polysiloxane or the above polysiloxane. A polysiloxane raw material capable of forming siloxane and a surface protective solution containing the silyl group-containing vinyl resin may be applied on the photosensitive layer and cured, but the latter method is preferred. This is because the polysiloxane is made three-dimensional by the curing, and the polysiloxane and the silyl group in the silyl group-containing vinyl resin are chemically bonded, whereby the adhesiveness to the photosensitive layer and the durability are further improved. The polysiloxane raw material, coating method, curing conditions and the like are the same as in the following more preferred embodiments.

In a more preferred embodiment, the surface protective layer comprises a surface protective layer containing a reaction product of the polysiloxane raw material and the silyl group-containing vinyl resin obtained by reacting the polysiloxane raw material and the silyl group-containing vinyl resin once. The solution is applied on the photosensitive layer and cured. By forming a surface protective layer by such a method, a structure in which polysiloxane and a silyl group-containing vinyl resin are chemically bonded, specifically, a structure of polysiloxane in which siloxane bonds are repeated three-dimensionally. A surface protective layer having a structure in which the silyl group of the silyl group-containing vinyl resin is incorporated therein can be easily obtained.

Specifically, first, a polysiloxane raw material is reacted with the silyl group-containing vinyl resin. The polysiloxane raw material may have any structure as long as the above-mentioned polysiloxane having a structure obtained by repeating a siloxane bond three-dimensionally can be formed.
The monomers listed as specific examples of the organosilane (I) and the low-molecular-weight products such as dimers and trimers thereof are exemplified. Among these, the monomers listed as specific examples of the organosilane (I) are preferably used, and more preferably the monomers listed as specific examples of the organosilane (I) are used.

The reaction weight ratio between the polysiloxane raw material and the silyl group-containing vinyl resin is such that the compounding ratio of the polysiloxane portion and the silyl group-containing vinyl resin portion in the obtained surface protective layer is within the above range. If you want, for example,
When the organosilane (I) is used as the polysiloxane raw material, the silyl group-containing vinyl resin is used in an amount of 25 to 400 parts by weight, preferably 45 to 250 parts by weight, based on 100 parts by weight of the organosilane (I).

At this time, it is preferable to add a metal chelate compound. Here, the metal chelate compound is a chelate compound of a metal selected from the group of zirconium, titanium and aluminum (hereinafter, referred to as metal chelate compound (IV)). The metal chelate compound (IV) promotes the hydrolysis and / or partial condensation reaction between the polysiloxane raw material and the silyl group-containing vinyl resin, and acts to promote the formation of a co-condensate of both components. Conceivable.

Examples of such a metal chelate compound (IV) include the general formulas Zr (OR ¹⁰ ) _p (R ¹¹ COCHCOR ¹² ) _4-p and Ti (OR ¹⁰ ) _q (R ¹¹ COCHCOR ¹² ) _4-q Or a compound represented by Al (OR ¹⁰ ) _r (R ¹¹ COCHCOR ¹² ) _3-r or a partial hydrolyzate of these compounds. R ¹⁰ and R ¹¹ in the metal chelate compound (IV) are each independently 1 to 6 carbon atoms.
Valent hydrocarbon group, specifically, ethyl group, n-propyl group, i-propyl group, n-butyl group, sec-butyl group, t-butyl group, n-pentyl group, n-hexyl group,
Cyclohexyl group, a phenyl group, R ¹² is, R ¹⁰
And other monovalent hydrocarbon groups for R ¹¹ the same carbon number 1-6, alkoxy group having 1 to 16 carbon atoms, specifically, methoxy group, ethoxy group, n- propoxy group, i- propoxy , N-butoxy group, sec-butoxy group, t-butoxy group, lauryloxy group, stearyloxy group and the like. Further, p and q are integers of 0 to 3, and r is an integer of 0 to 2.

Specific examples of such a metal chelate compound (IV) include zirconium tri-n-butoxyethylacetoacetate, zirconium di-n-butoxybis (ethylacetoacetate), and zirconium n-butoxytris (ethyl). Acetoacetate) zirconium, tetrakis (n-propylacetoacetate) zirconium, tetrakis (acetylacetoacetate) zirconium,
Zirconium chelate compounds such as tetrakis (ethylacetoacetate) zirconium; di-i-propoxy.
Bis (ethylacetoacetate) titanium, di-i-
Propoxy bis (acetyl acetate) titanium,
Titanium chelate compounds such as di-i-propoxy bis (acetylacetone) titanium; di-i-propoxy.
Ethyl acetoacetate aluminum, di-i-propoxy acetylacetonate aluminum, i-propoxy bis (ethyl acetoacetate) aluminum,
Aluminum such as i-propoxy bis (acetylacetonate) aluminum, tris (ethylacetoacetate) aluminum, tris (ethylacetate) aluminum, tris (acetylacetonato) aluminum, monoacetylacetonatobis (ethylacetoacetate) aluminum Chelate compounds and the like. Among these compounds, tri-n-butoxyethylacetoacetate zirconium, di-i-propoxybis (acetylacetonato) titanium, di-i-
Propoxy ethyl acetoacetate aluminum and tris (ethyl acetoacetate) aluminum are preferred. These metal chelate compounds (IV) can be used alone or in combination of two or more.

The amount of the metal chelate compound (IV) to be added is, for example, when organosilane (I) is used as a polysiloxane raw material, from the viewpoint of three-dimensional formation in the subsequent step and the pot life of the coating solution. ) And a silyl group-containing vinyl resin in an amount of 0.01
The amount is preferably from 50 to 50 parts by weight, preferably from 0.5 to 20 parts by weight.

The reaction conditions depend on the reactivity of the polysiloxane raw material to be used, and are not particularly limited as long as the obtained reactants are mild enough not to have siloxane bonds repeated three-dimensionally. For example, when organosilane (I) is used as a polysiloxane raw material, 60 to 8
The reaction is preferably performed at 0 ° C. for 4 to 6 hours.

An organic solvent is preferably present in the reaction system. As the organic solvent a usable here,
Alcohols, aromatic hydrocarbons, ethers, ketones, esters and the like are preferred. The amount of the organic solvent a used is not limited to the polysiloxane raw material, but is adjusted according to the purpose of use.

In this embodiment, without actually reacting the polysiloxane raw material with the silyl group-containing vinyl resin, a commercially available reactant of the polysiloxane raw material and the silyl group-containing vinyl resin, for example, glassca HPC7
Using 506 (manufactured by JSR), the reaction product may be dispersed in the organic solvent a to prepare a surface protection solution.

Next, a surface protection solution containing a reaction product of the obtained polysiloxane raw material and a silyl group-containing vinyl resin was used.
It is applied on the photosensitive layer and cured. If necessary, the above metal chelate compound (IV) may be further added to the surface protective liquid, or a curing accelerator described later may be added.

As a curing accelerator, naphthenic acid, octy
Alkaline such as luic acid, nitrous acid, sulfurous acid, aluminate, and carbonic acid
Li metal salts; sodium hydroxide, potassium hydroxide, etc.
Lucari compound: alkyl titanic acid, phosphoric acid, p-toluene
Acidic compounds such as enesulfonic acid and phthalic acid; ethylene
Diamine, hexanediamine, diethylenetriamine,
Triethylenetetramine, tetraethylenepentamine,
Piperidine, piperazine, metaphenylenediamine, d
Hardness of tanolamine, triethylamine, epoxy resin
Various modified amines used as an agent, γ-aminopro
Piltriethoxysilane, γ- (2-aminoethyl)-
Aminopropyltrimethoxysilane, γ- (2-amino
Ethyl) -aminopropylmethyldimethoxysilane, γ
-Amines such as anilinopropyltrimethoxysilane
Compound, (C_FourH₉)_TwoSn (OCOC₁₁H_{twenty three})_Two, (C_Four
H₉)_TwoSn (OCOCH = CHCOOCH_Three)_Two, (C_Four
H₉)_TwoSn (OCOCH = CHCOOC_FourH₉)_Two, (C₈
H₁₇)_TwoSn (OCOC₁₁H _{twenty three})_Two, (C₈H₁₇)_TwoSn
(OCOCH = CHCOOCH_Three)_Two, (C₈H₁₇)_TwoSn
(OCOCH = CHCOOC_FourH₉)_Two, (C₈H₁₇)_TwoS
n (OCOCH = CHCOOC₈H₁₇)_Two, Sn (OCO
CC₈H₁₇)_TwoCarboxylic acid type organotin compounds such as
(C_FourH₉)_TwoSn (SCH_TwoCOO)_Two, (C_FourH₉)_TwoSn
(SCH_TwoCOOC₈H₁₇)_Two, (C₈H₁₇)_TwoSn (SC
H_TwoCOO)_Two, (C₈H₁₇)_TwoSn (SCH _TwoCH_TwoCO
O)_Two, (C₈H₁₇)_TwoSn (SCH_TwoCOOCH_TwoCH_TwoO
COCH_TwoS)_Two, (C₈H₁₇)_TwoSn (SCH_TwoCOOC
H_TwoCH_TwoCH_TwoCH_TwoOCOCH_TwoS)_Two, (C₈H₁₇)_TwoS
n (SCH_TwoCOOC₈H₁₇)_Two, (C₈H₁₇)_TwoSn (S
CH_TwoCOOC₁₂H_{twenty five})_Two,

[0042]

Embedded image Mercaptide-type organotin compounds such as;

Embedded image Sulfide-type organotin compounds such as;

(C ₄ H ₉ ) ₂ SnO, (C ₈ H ₁₇ ) ₂ Sn
Reaction of organic tin oxides such as O, (C ₄ H ₉ ) ₂ SnO and (C ₈ H ₁₇ ) ₂ SnO with ester compounds such as ethyl silicate, ethyl silicate 40, dimethyl maleate, diethyl maleate and dioctyl phthalate Organotin compounds such as products are used.

By further adding the above metal chelate compound (IV) or a curing accelerator, the siloxane bond 3
Dimensioning can be reliably achieved. The amount of the metal chelate compound (IV) or the curing accelerator to be added to the surface protective solution depends on the strength of the film and the pot life of the coating solution, and the organosilane (I) used in the above reaction and the silyl group The amount is 0.1 to 80 parts by weight, preferably 0.5 to 60 parts by weight, based on 100 parts by weight of the total with the contained vinyl resin.

When the surface protective layer contains additives such as the above-mentioned fluorine-containing silicone compound, conductive metal fine particles, inorganic filler and organic fine particles, it is preferable to add the additives to the surface protective liquid.

At this time, the addition amount of each of the fluorine-containing silicone compound, conductive metal fine particles, inorganic filler and organic fine particles depends on the sum of the polysiloxane in the surface protective layer and the silyl group-containing vinyl resin as described above. It is sufficient that the compounding amount with respect to is within the above range. For example, when organosilane (I) is used as a polysiloxane raw material, the amount of the fluorine-containing silicone compound added is 5 parts by weight based on 100 parts by weight of the total of organosilane (I) and the silyl group-containing vinyl resin.
0 parts by weight or less, preferably 5 to 30 parts by weight, and the amount of the conductive metal fine particles added is 50 parts by weight or less, preferably 5 parts by weight or less.
To 30 parts by weight, the addition amount of the inorganic filler is 50 parts by weight or less, preferably 5 to 30 parts by weight, and the addition amount of the organic fine particles is 1 to 150 parts by weight, preferably 5 to 100 parts by weight. Is preferred.

The viscosity of the surface protective liquid is such that the thickness of the surface protective layer to be formed can be controlled within the above range and the protective layer can be formed uniformly.

In preparing the surface protective solution, an organic solvent b can be used in order to adjust the total solid concentration of the protective solution and also adjust the viscosity. Such organic solvents b include alcohols, aromatic hydrocarbons,
It is preferable to use organic solvents such as ethers, ketones and esters. Examples of the alcohols include monohydric or dihydric alcohols. Specific examples include methanol, ethanol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, and t-butyl alcohol. N-hexyl alcohol, n-octyl alcohol, ethylene glycol, diethylene glycol, triethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono n-propyl ether, ethylene glycol mono n-butyl ether, ethylene glycol monomethyl acetate Ether and ethylene glycol monoethyl ether acetate. Among them, monovalent saturated aliphatic alcohols having 1 to 8 carbon atoms are preferred. Further, specific examples of the aromatic hydrocarbons include:
Benzene, toluene, xylene and the like can be mentioned,
Specific examples of the ethers include tetrahydrofuran and dioxane. Specific examples of the esters include ethyl acetate, n-propyl acetate, n-butyl acetate, and propylene carbonate. These organic solvents can be used alone or in combination of two or more. The method for adding the organic solvent is not particularly limited, and the organic solvent can be added when preparing the surface protective solution and / or at an appropriate stage after the preparation.

The organic solvent b used here has a weight ratio of alcoholic solvent / other solvent of 80/20 to 100/0, preferably 90/10, so as not to attack the underlying photosensitive layer.
It is desirable to set it to 100/0.

In applying such a surface protective solution to the photosensitive layer, there are particularly restrictions as long as the thickness of the formed surface protective layer can be controlled within the above range and the protective layer can be formed uniformly. Instead, a known method, for example, a brush coating method, a spray coating method, a dipping method, a roll coating method, a flow coating method, a vacuum coating method, an air knife method, a doctor blade method, or the like can be adopted. These coating methods can be performed in a batch system, a semi-continuous system, or a continuous system.

After the surface protective liquid is applied on the photosensitive layer, curing, that is, three-dimensional siloxane bonding is performed. Specifically, the photosensitive layer coated with the solution is heated to a temperature of 60 to
Leave at 125 ° C., preferably 80-120 ° C., for 10-60 minutes, preferably 10-40 minutes. 125 temperature
If the temperature exceeds ℃, the electrostatic properties such as the sensitivity of the photosensitive layer are deteriorated. On the other hand, if the temperature is lower than 60 ° C, the siloxane bond tends to be incompletely three-dimensional, and the film becomes brittle.

As the photosensitive layer on which the surface protective layer as described above can be formed, a charge generating layer and a charge transport layer are sequentially laminated on a conductive support, and a charge transport layer and a charge generation layer are sequentially laminated. Any of a single-layer type including a charge transport material and a charge generation material may be used. Hereinafter, a photosensitive layer in which a charge generation layer and a charge transport layer are sequentially laminated on a conductive support will be described.

As the conductive support, a foil or plate of copper, aluminum, iron, nickel or the like in the form of a drum is used. In addition, these metals are vacuum-deposited, sputtered, or electroless-plated on a plastic film or the like, or a layer of a conductive compound such as a conductive polymer indium oxide or tin oxide is coated on paper or a plastic film, or is deposited or sputtered. Can be used. In general, cylindrical aluminum is used. Specifically, for example, after being extruded, a cold-drawn aluminum pipe (ED pipe), and after extrusion, a drawn aluminum pipe is cut, and the aluminum pipe is cut. The outer surface is cut and finished using a cutting tool such as a diamond tool with a cutting tool of about 0.2 to 0.3 mm (cutting tube). After impact processing of an aluminum disk into a cup shape, the outer surface is finished by ironing (EI
Tube), and an aluminum disk which is deep drawn and then the outer surface is finished by ironing (DI tube). Further, those obtained by further cutting or anodizing these surfaces may be used.

A charge generation layer and a charge transfer layer are sequentially formed on such a conductive support. Prior to this, a subbing layer may be formed for the purpose of preventing charge injection from the conductive support. preferable.

When the undercoat layer is provided, the material may be a polymer such as polyimide, polyamide, nitrocellulose, polyvinyl butyral, polyvinyl alcohol, polyacrylate or the like, or a low resistance compound such as tin oxide or indium oxide dispersed therein. Or a deposited film of aluminum oxide, zinc oxide, silicon oxide, or the like. In this case, the thickness of the undercoat layer is desirably 1 μm or less.

The charge generation layer may be formed by vacuum deposition of the charge generation material, by dissolving the charge generation material in a solvent such as an amine and coating and drying, or by coating the charge generation material with an appropriate solvent or a pigment. If there is, it is formed by applying a coating liquid prepared by dispersing in a solution in which a binder resin is dissolved, and drying the coating liquid.

Examples of the charge generating material include bisazo pigments, triarylmethane dyes, thiazine dyes, oxazine dyes, xanthene dyes, cyanine dyes,
Styryl dyes, pyrylium dyes, azo dyes, chiacdrine dyes, indigo pigments, perylene pigments, polycyclic quinone pigments, bisbenzimidazole pigments, indathrone pigments, squarylium pigments, phthalocyanine pigments, etc. Organic substances. In addition, any material that absorbs light and generates charge carriers with extremely high efficiency can be used.

The charge transport layer is formed by applying a coating solution prepared by dispersing a charge transport material in a solution in which a binder resin is dissolved on the charge generation layer and drying the coating solution.

As the charge transporting material, an organic substance is preferable. For example, hydrazone compounds, pyrazoline compounds, styryl compounds, triphenylmethane compounds, oxadiazole compounds, carbazole compounds, stilbene compounds,
Various materials such as an enamine compound, an oxazole compound, a triphenylamine compound, a tetraphenylbenzidi compound, and an azine compound are exemplified.

The binder resin used in the production of the above-mentioned photoreceptor is electrically insulating, and is measured by 1 × 10 ¹²
It is desirable to have a volume resistance of Ω · cm or more. For example, a binder such as a thermoplastic resin, a thermosetting resin, a photocurable resin, or a photoconductive resin known per se can be used. Specifically, polyester resin, polyamide resin, acrylic resin, ethylene-vinyl acetate resin, ion-crosslinked olefin copolymer (ionomer), styrene-
Thermoplastic resins such as butadiene block copolymer, polycarbonate, butyral resin, phenoxy resin, vinyl chloride-vinyl acetate copolymer, cellulose ester, polyimide, styrene resin; epoxy resin, urethane resin, silicone resin, phenol resin, and melamine resin ,
Thermosetting resins such as xylene resins, alkyd resins, and thermosetting acrylic resins; photocurable resins; photoconductive resins such as polyvinylcarbazole, polyvinylpyrene, polyvinylanthracene, and polyvinylpyrrole; and the like. Used alone or in combination of two or more.

When the charge transporting material is a polymeric charge transporting material that can be used as a binder, it is not necessary to use another binder resin.

In the photosensitive layer, a plasticizer such as halogenated paraffin, polychlorinated biphenyl, dimethylnaphthalene, dibutyl phthalate, O-terphenyl, chloranil, tetracyanoethylene, 2,4,7,
An electron-withdrawing sensitizer such as trinitrofluorenone, 5,6-dicyanobenzoquinone, tetracyanoquinodimethane, tetrachlorophthalic anhydride, 3,5-dinitrobenzoic acid, methyl violet, rhodamine B, cyanine dye, pyrylium salt And sensitizers such as thiapyrylium salts.

The coating of the photosensitive layer can be performed using various coating apparatuses such as known ones. Specifically, for example, using an applicator, a spray coater, a bar coater, a dip coater, a roll coater, a doctor blade or the like. Can be done.

The electrophotographic photoreceptor as described above has excellent electrostatic properties such as adhesion, durability and sensitivity between the surface protective layer and the photosensitive layer, and does not cause problems such as cracks.

The electrophotographic apparatus of the present invention may have any configuration as long as it includes the above-described electrophotographic photosensitive member and an intermediate transfer member for transferring a toner image formed on the photosensitive member. By transferring the toner image on the photosensitive member to the intermediate transfer member using such a photosensitive member, the transfer efficiency to the intermediate transfer member is improved.

A preferred electrophotographic apparatus according to the present invention comprises: a latent image forming means for forming an electrostatic latent image on the electrophotographic photosensitive member; a developing means for developing the electrostatic latent image to form a toner image; First transfer means for transferring the toner image to the intermediate transfer member,
A second transfer unit that transfers the toner image on the intermediate transfer member to a transfer material; A preferred electrophotographic apparatus of the present invention is
Further, if necessary, other means, for example, a light removing means, a fixing means and the like are provided. Hereinafter, each means in the preferred electrophotographic apparatus of the present invention will be described.

The latent image forming means is not particularly limited as long as it has a function of forming an electrostatic latent image on the electrophotographic photosensitive member. For example, a charging means for charging the electrophotographic photosensitive member And a latent image forming means having an image exposing means for imagewise exposing the image and, if necessary, other means.

The charging means is not particularly limited.
For example, a known charger such as a contact-type charger using a conductive or semi-conductive roller, brush, film, rubber blade, or the like, a scorotron charger using a corona discharge, or a corotron charger may be used. The charging unit normally applies a direct current to the electrophotographic photoreceptor, but may apply an alternating current further superimposed.
The electrophotographic photosensitive member is usually charged to -300 to -1000 V by such a charging means, for example.

The image exposure means is not particularly limited. For example, an optical system device capable of exposing a light source such as a semiconductor laser light, an LED light, a liquid crystal shutter light or the like to the surface of the electrophotographic photosensitive member in a desired image. And the like.

The developing means has a function of developing the electrostatic latent image formed on the electrophotographic photosensitive member to form a toner image. Development is a known normal development of a method of attaching toner charged to the opposite polarity to the electrostatic latent image to the latent image,
A well-known reversal development method of attaching toner charged to the same polarity as the electrostatic latent image to the latent image may be used. The development is
The development can be carried out using a general developing means for developing by contacting or non-contacting a magnetic or non-magnetic one-component developer or a two-component developer. Such a developing unit is not particularly limited as long as it has the above-mentioned function, and can be appropriately selected depending on the purpose.For example, the one-component developer or the two-component developer may be used. A known developing device having a function of attaching to the electrophotographic photosensitive member using a brush, a roller, or the like can be used.

The first transfer means has a function of transferring the toner image formed on the electrophotographic photosensitive member by development to an intermediate transfer member. In this specification, the transfer of the toner image to the intermediate transfer member is referred to as “first transfer”.

The first transfer means is not particularly limited as long as it has the above-mentioned functions. For example, a contact-type transfer charger using a belt, a roller, a film, a rubber blade, or the like, or a corona discharge is used. Known transfer chargers such as a scorotron transfer charger and a corotron transfer charger are known. In the present invention, a peeling charger and the like can be used in addition to the transfer charger. In addition, during the first transfer, a direct current is usually used as a transfer current applied from the first transfer unit to the electrophotographic photosensitive member. In the present invention, an alternating current is further superimposed. May be used. The setting conditions in the first transfer unit vary depending on the image area width to be charged, the shape of the transfer charger, the opening width, the process speed (peripheral speed), and the like, and cannot be unconditionally defined. The current is +100 to +400 μA, and the primary transfer voltage is +
500 to +2000 V can be set as the set value.

The structure of the intermediate transfer member is generally a multilayer structure. For example, an at least one elastic layer formed of rubber, elastomer, resin, etc., and at least one coating layer are formed on a chargeable support. And a structure provided with a layer. The shape of the intermediate transfer member is not particularly limited and may be appropriately selected depending on the intended purpose. Examples of the shape include a roller shape and a belt shape.
In the present invention, among these, the endless belt shape is particularly preferable in terms of color misregistration at the time of superimposing images, durability due to repeated use, and ease of arrangement of other subsystems.

As the material of the intermediate transfer member, for example,
Conductive carbon particles and metal powder for polyurethane resin, polyester resin, polystyrene resin, polyolefin resin, polybutadiene resin, polyamide resin, polyvinyl chloride resin, polyethylene resin, fluorine resin, etc. And the like are preferably used. Among these, those obtained by dispersing carbon particles in a polyurethane resin can be suitably used.

The surface volume resistance of the intermediate transfer member is preferably, for example, 10 ⁸ to 10 ¹⁶ Ωcm. If the surface volume resistance value is less than 10 ⁸ Ωcm, bleeding or thickening occurs in the image, and if it exceeds 10 ¹⁶ Ωcm, scattering of the image occurs, and the need for static elimination of the intermediate transfer body sheet occurs.
Either case is not preferred. The thickness of the intermediate transfer member is preferably, for example, about 50 to 200 μm.

The second transfer means has a function of collectively transferring the toner image on the intermediate transfer member to a transfer material. In this specification, the transfer of the toner image to the transfer material is referred to as “second transfer”.

The second transfer means is not particularly limited as long as it has the above-mentioned functions. For example, the contact type transfer charger, scorotron transfer charger, corotron transfer charger exemplified as the first transfer means And the like. In addition, during the second transfer, a direct current is usually used as a transfer current applied from the second transfer means to the intermediate transfer member, but in the present invention, an alternating current is further superimposed and used. May be.

The setting conditions in the second transfer means vary depending on the image area width to be charged, the shape of the transfer charger, the opening width, the process speed (peripheral speed), etc., and cannot be specified unconditionally. The secondary transfer current is +100 to +400 μA, and the secondary transfer voltage is +20.
00 to +5000 V can be set as the set value.

The other means include, for example, a light erasing means for light erasing the electrophotographic photosensitive member, a fixing means for fixing the second transferred toner image on the transfer material, and an electrophotographic photosensitive member. An electrophotographic photosensitive member cleaner for cleaning, an intermediate transfer member cleaner for cleaning the intermediate transfer member, and the like can be given.

The light neutralizing means includes, for example, a tungsten lamp and an LED, and the light quality used in the light neutralizing process includes, for example, white light such as a tungsten lamp and red light such as an LED light. Can be The intensity of the irradiation light in the photostatic process is usually several times to 30 times the amount of light indicating the half-reduction exposure sensitivity of the electrophotographic photosensitive member.
The output is set to be about twice.

The fixing means is not particularly limited.
A fixing device known per se, for example, a hot roll fixing device, an oven fixing device and the like can be mentioned.

An example of the electrophotographic apparatus of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic explanatory view showing a color electrophotographic apparatus according to one embodiment of the electrophotographic apparatus of the present invention. Here, a reversal developing means is used as the developing means.

The electrophotographic apparatus shown in FIG. 1 can be used as a copying machine, a laser beam printer or the like.
The electrophotographic apparatus shown in FIG. 1 includes an electrophotographic photosensitive member 1, a charging unit 2, an image exposure unit 3 (a color separation / imaging exposure optical system for a document image, and a time series electric digital pixel signal for image information. And a multi-color developing device including four developing units of a magenta developing device 41, a cyan developing device 42, a yellow developing device 43, and a black developing device 44. Reversal developing means 4, an electrophotographic photosensitive member cleaner 5,
An intermediate transfer member 6, a first transfer unit 7, an intermediate transfer member cleaner 8, a second transfer unit 9, and a heat roller fixing device as a fixing unit 10 are provided.

The electrophotographic photosensitive member 1 is the above-described electrophotographic photosensitive member of the present invention, and has a drum shape. The electrophotographic photoreceptor 1 may be called a photoreceptor drum. The electrophotographic photosensitive member 1 is rotatably provided in an electrophotographic apparatus at a predetermined peripheral speed (process speed) in a counterclockwise direction indicated by an arrow, and a corona discharge device as a charging unit 2 is provided around the electrophotographic photosensitive member 1. An image exposing device as an image exposing device 3, a reversal developing device 4 as a multicolor developing device,
An electrophotographic photosensitive member cleaner 5 is provided.

An endless belt-shaped intermediate transfer member 6 is arranged between the reversal developing means and the electrophotographic photosensitive member cleaner 5. The intermediate transfer member 6 includes three rollers and a first roller.
The transfer charger as the transfer means 7 is rotatable in the clockwise direction of the arrow at the same peripheral speed as the electrophotographic photosensitive member 1, and the intermediate transfer body 6 located on the transfer charger as the first transfer means 7 Are in contact with the electrophotographic photosensitive member 1. Of the three rollers, the roller located next to the transfer charger as the first transfer means 7 and the transfer roller as the second transfer means 9 are arranged to face each other, and are in contact with these. The recording paper 11 moves on the interface by these rotational driving forces.

In the electrophotographic apparatus shown in FIG. 1, the electrophotographic photosensitive member 1 is driven to rotate. In conjunction with this, the corona discharger as the charging means 2 is driven, and the electrophotographic photosensitive member 1
Is uniformly charged to a predetermined polarity and potential. Next, the electrophotographic photosensitive member 1 whose surface is uniformly charged is imagewise exposed by an image exposing device as an image exposing means 3, and an electrostatic latent image is formed on the surface.

Subsequently, the electrostatic latent image is developed by reversal developing means 4 as a multicolor developing device. More specifically, first, development with magenta toner is performed by the magenta developing device 41 of the four developing units provided in the reversal developing means 4. Next, the reversal developing means 4 rotates, and the cyan developing device 42 moves to a position facing the electrophotographic photosensitive member 1. Then, the development with the cyan toner is performed by the cyan developing device 42. Next, the reversal developing means 4 rotates, and the yellow developing device 43 moves to a position facing the electrophotographic photosensitive member 1. Then, the yellow developing device 43 performs development with yellow toner. Next, the reversal developing unit 4 rotates, and the black developing device 44 moves to a position facing the electrophotographic photosensitive member 1. Then, the black developing device 44 performs development using the black toner. As a result, the superimposed transfer using the four color toners is performed, and a composite color toner image corresponding to the target color image is formed on the electrophotographic photosensitive member 1.

Note that the above-described development with four colors is performed independently for each color, and while the development with one color is not performed, the development with other colors is not performed. Color development is not affected by other color developers. Specifically, an electrostatic latent image corresponding to a first color component image (for example, a magenta component image) of a target image is first formed. Next, the magenta developing device 41 develops the electrostatic latent image with magenta toner. At this time, the cyan developing device 4
2. Since the developing units of the yellow developing unit 43 and the black developing unit 44 are in the OFF state, they do not act on the electrophotographic photoreceptor 1, and the image developed with the magenta toner is
Unaffected by 2-44. As described above, development with the four color toners is sequentially performed on the electrophotographic photosensitive member 1.

This toner image is applied to the intermediate transfer member 6 from a transfer charger serving as first transfer means 7 to be driven in the process of passing through the interface (nip portion) between the electrophotographic photosensitive member 1 and the intermediate transfer member 6. The primary (intermediate) transfer is sequentially performed on the outer peripheral surface of the intermediate transfer body 6 by the electric field formed by the primary transfer bias. Note that a primary transfer bias for sequentially superimposing transfer of four color toner images from the electrophotographic photosensitive member 1 to the intermediate transfer member 6 is applied from a bias power supply with a polarity opposite to that of the toner. In this electrophotographic apparatus, the second transfer means 9 and the intermediate transfer member cleaner 8 are moved from the intermediate transfer member 6 when the four-color toner image is superimposed and transferred from the electrophotographic photosensitive member 1 to the intermediate transfer member 6. Can be separated.

Thereafter, the toner remaining on the electrophotographic photosensitive member 1 is cleaned and removed by the electrophotographic photosensitive member cleaner 5. Then, the electrophotographic photosensitive member 1 is subjected to the next copy cycle.

On the other hand, the composite color toner image superimposedly transferred onto the intermediate transfer member 6 is transferred between the intermediate transfer member 6 and the transfer roller 9 by the contact charging action (transfer bias) of the transfer roller as the second transfer means 9. The recording paper 1 supplied to the contact nip from the paper cassette 12 sequentially at a predetermined timing.
1 is transferred.

Next, the recording paper 11 is transferred into a heat roller fixing device as the fixing means 10, and inside the fixing device,
The toner image on the recording paper 11 is thermally fixed. From the above,
A desired image is formed on the recording paper 11. Then, after the image formation on the recording paper 11 is completed, the residual toner on the intermediate transfer body 6 is cleaned and removed by the intermediate transfer body cleaner 8.

The electrophotographic apparatus of the present invention as described above has excellent toner transfer efficiency from the surface of the photosensitive member to the intermediate transfer member. The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. In the examples, “parts” means “parts by weight” unless otherwise specified.

[0094]

EXAMPLES Synthesis of Silyl Group-Containing Vinyl Resin (A) As monomers, 65 parts of methyl methacrylate, 35 parts of n-butyl acrylate, 20 parts of γ-methacryloxypropyltrimethoxysilane (SZ6030: Dow Corning Toray Silicone) Then, 16 parts of 2-hydroxyethyl methacrylate was mixed and dissolved in 130 parts of isopropyl alcohol, and the mixture was stirred at 80 ° C. A solution obtained by dissolving 4 parts of azobisisobutyronitrile in 10 parts of tetrahydrofuran was added dropwise and reacted for 4 hours to obtain a silyl group-containing vinyl resin (A) having a solid concentration of 50%.

Synthesis of Silyl Group-Containing Vinyl Resin (B) As monomers, 65 parts of methyl methacrylate, 35 parts of n-butyl acrylate, 20 parts of γ-methacryloxypropyltrimethoxysilane (SZ6030: Dow Corning Toray Silicone), 10 parts of N-methylolacrylamide and 6 parts of acrylic acid were mixed and dissolved in 130 parts of isopropyl alcohol, and the mixture was stirred at 80 ° C. A solution obtained by dissolving 4 parts of azobisisobutyronitrile in 10 parts of xylene was added dropwise and reacted for 4 hours to obtain a silyl group-containing vinyl resin (B) having a solid concentration of 50%.

Example 1 JIS 5657 cylindrical aluminum alloy (outer diameter 100
(mm, length 350 mm, thickness 2 mm) was cut with a cutting tool using natural diamond as a cutting blade. Using this as a degreasing agent, surfactant Alclean 161
Degreasing treatment was performed at 60 ± 5 ° C. for 5 minutes using 30 g / l (manufactured by Okuno Pharmaceutical Co., Ltd.) and washed with running water. 100g / l
After immersion in a nitric acid solution for 5 minutes to perform an etching treatment, the substrate was washed with running water. Next, as an electrolytic solution, 150 g / l
Of sulfuric acid, current density 1 (A / dm ² ), liquid temperature 20
Anodizing treatment was performed at 15 ° C. for 15 minutes to form an anodized layer having a thickness of 8 μm. After this was washed with running water with pure water, sealing treatment was performed at 90 ° C. for 30 minutes using an aqueous solution containing a sealing agent containing nickel acetate (Sealing Salt AS: manufactured by Clariant Japan KK) at 8 g / l. . Next, a photosensitive layer was formed on the photoreceptor substrate on which the anodic oxide layer had been sealed as described above, as follows.

4.5 parts of X-type phthalocyanine (8120B: manufactured by Dainippon Ink Industries, Ltd.), 2.5 parts of butyral resin (Eslek BH-3: manufactured by Sekisui Chemical Co., Ltd.) and phenoxy resin (PKHH; manufactured by Union Carbide) 2.5 parts were dispersed with a sand mill together with 500 parts of dichloroethane. The obtained dispersion was applied onto the above-mentioned photoreceptor substrate so that the film thickness after drying was 0.3 μm to form a charge generation layer. Then, the following general formula:

Embedded image A coating solution obtained by dissolving 40 parts of a styryl compound, 60 parts of a polycarbonate resin (TS-2050: manufactured by Teijin Chemicals Ltd.) and 2 parts of a phenolic compound butylhydroxytoluene (special grade: manufactured by Tokyo Chemical Industry Co., Ltd.) in 400 parts of tetrahydrofuran Is applied on the charge generation layer and dried to form a 20 μm
m of the charge transport layer was formed.

Next, a surface protective solution was obtained as follows. 30 parts of dimethyldimethoxysilane (AY43-004: Dow Corning Toray Silicone), 80 parts of methyltrimethoxysilane (SZ6070: Dow Corning Toray Silicone), 50 parts of a silyl group-containing vinyl resin (A) and aluminum tris ( Ethyl acetoacetate)
20 parts were mixed with 40 parts of isopropyl alcohol and 30 parts of ion-exchanged water, and reacted at 60 ° C. for 5 hours. After cooling, 20 parts of acetylacetone was added, and the resin solution (1) was added.
I got To the resin solution (1), 20 parts of a fluorine-containing silicone compound (X-12-2500; manufactured by Shin-Etsu Chemical Co., Ltd.) was further added and mixed. 8 parts of the obtained resin solution, 2 parts of dibutyltin dimaleate as a curing accelerator and 20 parts of isopropyl alcohol were mixed to prepare a surface protective solution. The obtained surface protective solution is coated on the charge transport layer with a thickness of 2 after drying.
μm, and dried at 120 ° C. for 10 minutes to form a surface protective layer to prepare an electrophotographic photosensitive member. No cracks occurred in the surface protective layer.

Example 2 The same procedure was performed as in Example 1 except that the protective layer was formed as described below. Silyl group-containing vinyl resin (A) to (B)
A resin solution (1) was obtained in the same manner as in Example 1 except that the above procedure was replaced. To this resin solution (1), 20 parts of organic fine particles of polytetrafluoroethylene (KD-500AS; manufactured by Kitamura Co., Ltd.) having an average particle diameter of 0.3 μm were further added and dispersed in a sand mill for 60 hours. 8 parts of the obtained resin solution, 2 parts of dibutyltin dimaleate as a curing accelerator and 20 parts of isopropyl alcohol were mixed to prepare a surface protective solution.
The obtained surface protective solution was applied on the above-mentioned charge transport layer so that the film thickness after drying was 2 μm, and dried at 120 ° C. for 10 minutes to form a surface protective layer to prepare an electrophotographic photoreceptor. . No cracks occurred in the surface protective layer.

Example 3 The same procedure was performed as in Example 1 except that the protective layer was formed as described below. Glaska HPC7506 (JSR) which is a reaction product of an organosilane and a silyl group-containing vinyl resin.
1 part of a fluorine-containing silicone compound (X-12-2500; manufactured by Shin-Etsu Chemical Co., Ltd.) together with 20 parts of isopropyl alcohol. Thereafter, 2 parts of a curing agent HPC404 (manufactured by JSR), which is a tin compound, was added to obtain a surface protection liquid. The obtained surface protective liquid was applied on the charge transport layer so that the film thickness after drying was 2 μm.
After drying for a minute, a surface protective layer was formed to prepare an electrophotographic photosensitive member. No cracks occurred in the surface protective layer.

Comparative Example 1 An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the vinyl resin having a silyl group was omitted from the surface protective layer of Example 1.

Comparative Example 2 A polysiloxane, Glasca HPC7003 (JSR
9 parts, curing agent HPC401 (manufactured by JSR) 0.3
Parts, acrylic polyol urethane PG60 (Kansai Paint) 2 parts, polyamide resin CM8000 (Toray)
An electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that 0.6 part was dispersed and dissolved in 20 parts of isopropyl alcohol to prepare a surface protective solution, and the surface protective solution was used.

Comparative Example 3 Without providing a surface protective layer, a resin of the charge transport layer of Example 1 was copolymerized with a structural unit represented by the following general formulas (a) and (b) (where the component of the general formula (a) was An electrophotographic photoreceptor was prepared in the same manner as in Example 1, except that the copolymer was 50% by weight based on the total weight of the polymer; the viscosity average molecular weight was 2.21 × 10 ⁴ ).

[0104]

Embedded image

(Evaluation) Electrostatic Characteristics The obtained photoreceptor was converted to a commercially available electrophotographic copying machine (CF90).
0: manufactured by Minolta Co., Ltd.), charged to -1 KV, initial surface potential (V0 (V)), exposure required for reducing the initial potential to １ ／: sensitivity (E1 / 2 (μJ / cm) ² ))
Decay DD when the surface potential is left in the dark for 5 seconds
R5 (%) was measured.

Transferability The transferability was evaluated. The obtained photoreceptor was mounted on a commercially available electrophotographic copying machine (CF900: manufactured by Minolta Co., Ltd.), and the transferability after 10,000 continuous copies was evaluated. The transferability was indicated by a value (%) calculated according to the following formula.

[0107]

(Equation 1)

The above results are summarized in Table 1.

[Table 1]

[0109]

According to the present invention, an excellent effect that the toner transfer efficiency from the photosensitive member surface to the intermediate transfer member is improved can be obtained. Further, the photoreceptor employed in the apparatus of the present invention has excellent electrostatic properties such as adhesion, durability and sensitivity between the surface protective layer and the photosensitive layer, and does not cause problems such as cracks.

[Brief description of the drawings]

FIG. 1 shows a schematic configuration diagram of an example of an electrophotographic apparatus of the present invention.

[Explanation of symbols]

1: electrophotographic photosensitive member, 2: charging means, 3: image exposure means,
4: developing means, 5: electrophotographic photosensitive member cleaner, 6: intermediate transfer body, 7: first transfer means, 8: intermediate transfer body cleaner,
9: second transfer means, 10: fixing means, 11: recording paper, 1
2: paper feed cassette, 41: magenta developing device, 42: cyan developing device, 43: yellow developing device, 44: black developing device.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H068 AA02 AA03 AA04 BA58 BB07 BB08 BB10 BB17 BB32 BB33 BB57 FC11

Claims (4)

[Claims] 1. A latent image forming means for forming an electrostatic latent image on an electrophotographic photosensitive member having at least a photosensitive layer and a surface protective layer sequentially provided on a conductive support, and developing the electrostatic latent image. An electrophotographic apparatus comprising: developing means for forming a toner image; first transfer means for transferring the toner image to an intermediate transfer member; and second transfer means for transferring the toner image on the intermediate transfer member to a transfer material. An electrophotographic apparatus, wherein the surface protective layer of the electrophotographic photosensitive member comprises at least polysiloxane and a silyl group-containing vinyl resin. 2. The electrophotographic apparatus according to claim 1, wherein the surface protective layer of the electrophotographic photosensitive member is formed by chemically bonding at least polysiloxane and a silyl group-containing vinyl resin. 3. The surface protective layer of the electrophotographic photosensitive member is coated with a surface protective solution containing a reactant obtained by reacting at least a polysiloxane raw material and a silyl group-containing vinyl resin on the photosensitive layer. The electrophotographic apparatus according to claim 1, wherein the electrophotographic apparatus is cured. 4. The electrophotographic apparatus according to claim 3, wherein the surface protective liquid further contains a fluorine-containing silicone compound.