JP2003005532A - Intermediate transfer body for electrophotographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intermediate transfer body for electrophotography which drastically suppresses the fluctuation in resistance by an environment fluctuation, makes high-quality images obtainable without using intricate control and is adequately used for appellations, such as a color laser printer in particular where high image quality is obtainable. SOLUTION: This intermediate transfer body for electrophotography is a semiconductive roller consisting of a metallic supporting member, a semiconductive elastic layer formed on the outer peripheral surface of this supporting member and coating layers consisting of at least one layer formed on its outer peripheral surface. The semiconductive elastic layer described above contains an inorganic metal salt and a polyoxyethylene compound as a conductivity imparting agent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to an intermediate transfer member used in an electrophotographic apparatus such as a printer or a facsimile receiver.

[0002]

2. Description of the Related Art As an intermediate transfer member of a dry electrophotographic apparatus, an intermediate transfer member using a semiconductive elastic body has been attracting attention and is used for an intermediate transfer drum and the like. Here, the intermediate transfer member is a member that temporarily transfers and carries the toner image formed on the photoconductor onto the surface of the member from the photoconductor, and then retransfers the toner image onto a recording material such as paper. Conventionally, the toner image on the photoconductor is directly transferred onto the recording material.
In recent years, color images of electrophotographic devices have been rapidly developed, but in order to form a color image, generally, four color images of cyan, magenta, yellow, and black are formed by separate photosensitive devices and superimposed. Need to match. However, when the four-color image is directly superimposed on a recording material such as paper, the dimensional stability of the recording material is not good, which causes color misregistration and greatly deteriorates the image quality. Therefore, a so-called intermediate transfer method, in which images of four colors are once superposed on an intermediate transfer member and then transferred onto a recording material, has been noticed and used.

For the semiconductive elastic layer of the intermediate transfer member used for these purposes, a polymer elastomer such as rubber or polyurethane or a polymer foam material has been usually used. The properties required for these semiconductive elastic bodies are that they have a rubber hardness capable of forming a stable contact area with the photoconductor, and that the plasticizer does not exude and contaminate the photoconductor. In addition, it is required to stably have a predetermined resistance value in the medium resistance region of 10 ⁵ to 10 ⁹ Ω.
Generally, in order to obtain a member in the medium resistance region as described above using a polymer elastomer or foam, an ion conductive substance such as powder of metal or metal oxide, carbon black, or sodium perchlorate is added. A method is used. However, when the resistance is controlled to a medium resistance region necessary for an intermediate transfer member for electrophotography, etc., by using a powder of metal or metal oxide, carbon black, etc., there is a large variation in the position of the electric resistance, and the electric resistance is large. There was a problem that the voltage dependency of the resistance was large. If the electric resistance of the intermediate transfer member has a large variation in position, the transfer efficiency varies in each transfer process from the photoconductor to the intermediate transfer member and from the intermediate transfer member to the recording material, which causes deterioration of image quality. Since the intermediate transfer member mediates the two transfer processes from the photoconductor to the intermediate transfer member and from the intermediate transfer member to the recording material as described above, it has an optimum resistance value according to the resistance of the photosensitive body and the recording material. There is a need. For this purpose, it is necessary to control the resistance value at each voltage used for transfer within the required resistance range. Therefore, if the voltage dependency of the resistance value of the intermediate transfer member is large, the resistance control range is very narrow. There was a problem saying that.

On the other hand, when a polymer material having polarity is mixed with an ion conductive substance such as sodium perchlorate, variations in resistance and voltage dependence of resistance are substantially achieved in the medium resistance region. It is known that non-polymeric components can be produced. However, such a polymer member
Resistance in high temperature and high humidity environment such as 32.5 ℃, 85%,
There has been a problem that the difference in resistance is large in a low temperature and low humidity environment such as 15 ° C. and 10%, and the resistance greatly varies depending on the environment in which it is used. In order to suppress the effect of resistance fluctuation due to such environmental changes, usually, temperature and humidity are monitored by a temperature sensor and a humidity sensor to correct resistance fluctuation, that is, the resistance value is calculated from the temperature and humidity values. A method of predicting and applying electrical control such as changing the applied voltage was used. However, in general, such environmental changes in resistance of polymer members are not changes that can be replaced by simple functions, and there is also a time delay with respect to environmental changes, so it is impossible to accurately predict resistance, Therefore, it was virtually impossible to completely eliminate these effects.

Further, in recent years, colorization and high speed have been demanded, and the demand for image quality has become more and more strict, and under the present circumstances, more and more complicated control is being performed to correct resistance fluctuation. As means for solving such a problem, JP-A No. 11-293128 describes a conductive composition in which a polar polymer compound contains a quaternary ammonium salt having an amide bond. However, even if such a means is used, the difference between the resistance in a high temperature and high humidity environment such as 32.5 ° C and 85% and the resistance in a low temperature and low humidity environment such as 15 ° C and 10% is about 20 times. The reality is that a control mechanism for compensating for the influence of resistance change due to environmental changes is still needed.

[0006]

The present invention solves the drawbacks of the conventional semiconductive elastic material, significantly suppresses the resistance change due to the environmental change, and obtains a high quality image without using complicated control. In particular, it is an object of the present invention to provide an intermediate transfer member suitable for use in applications requiring high quality image quality such as color laser printers.

[0007]

In order to solve the above problems, the inventors of the present invention have made extensive studies and as a result, as a conductivity imparting agent, a semiconductive composition comprising a reaction product of a conductive curable composition. In the case of using a material as a semiconductive elastic layer, it has been found that the resistance fluctuation due to environmental changes can be suppressed by using a semiconductive composition containing an inorganic metal salt and a polyoxyethylene compound as the semiconductive elastic layer. Came to.

That is, the present invention comprises a metal supporting member, a semiconductive elastic layer formed on the outer peripheral surface of the supporting member, and a coating layer formed on the outer peripheral surface of at least one layer. An electrophotographic intermediate transfer member for electrophotography (claim 1), characterized in that the semiconductive elastic layer contains an inorganic metal salt and a polyoxyethylene compound as a conductivity-imparting agent. The present invention relates to an electrophotographic intermediate transfer member (claim 2), wherein the member has the characteristics (1) to (3). (1) 10 in an environment of 23 ° C. and 55% relative humidity
The roller resistance measured by applying a DC voltage of 00V is 1
It is not less than 0 ⁵ Ω and not more than 10 ⁹ Ω. (2) 50% in an environment of 23 ° C and 55% relative humidity
When the roller resistance measured by applying a DC voltage of 0 V and 1000 V is R ₅₀₀ and R ₁₀₀₀ , the value of R ₅₀₀ / R ₁₀₀₀ is 0.8 or more and 1.2 or less. (3) Roller resistance RLL measured by applying a DC voltage of 1000 V in an environment of 15 ° C. and 10% relative humidity, and 3
Ratio RLL / R of roller resistance RHH measured by applying a DC voltage of 1000 V in an environment of 2.5 ° C. and relative humidity of 85%
HH is 10 or less.

In the present invention, the semiconductive elastic layer has at least one alkenyl group in the molecule (A),
A conductive curable composition containing as a main component a polymer in which the repeating unit constituting the main chain is an oxyalkylene unit, (B) a curing agent having two or more hydrosilyl groups in the molecule, and (C) a hydrosilylation catalyst. A semi-conductive roller comprising a reaction product of a substance (claim 3), wherein the inorganic metal salt is at least one selected from a metal of Group 1 and a metal of Group 2 of the periodic table.
The present invention relates to an intermediate transfer member (claim 4) which is at least one kind of inorganic metal salt.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. FIG. 1 is a configuration diagram of an intermediate transfer type electrophotographic apparatus which is an embodiment of an image recording apparatus of the present invention. A surface of an electrophotographic photosensitive member 101 formed by applying a photosensitive material on an aluminum pipe is uniformly charged by a charging roller 102, and then scanning exposure light 104b emitted from a writing device 104a according to image information. Due to
An electrostatic latent image is formed on the surface of the photoconductor. This electrostatic latent image is
Of the developing devices 105, the developing device 105a corresponding to the color information of the electrostatic latent image formed this time develops and visualizes. The visualized toner image is the electrophotographic photoreceptor 10.
1 and the intermediate transfer roller 110 contact the transfer area P1
In the above, the image is transferred from the electrophotographic photosensitive member 101 to the surface of the intermediate transfer roller 110 by applying a voltage between the intermediate transfer roller and the photosensitive member from a power source (not shown). After the transfer, the surface of the photoconductor is irradiated with light from the static elimination lamp 108 to eliminate the charge, and the toner remaining on the surface of the photoconductor is removed by the cleaning device 103. The above steps are repeated a plurality of times, and each time development and visualization is performed by the developing devices 105b, 105c, 105d having developers having different colors according to the image information, and the intermediate transfer drum 110 is transferred from the surface of the photosensitive member.
Then, a plurality of toner images are laminated and formed on the surface of the intermediate transfer drum. The color toner image formed on the surface of the intermediate transfer drum is printed on the paper transport roll 1
The recording material 112 that is conveyed by the recording medium 112 and is located between the intermediate transfer drum 110 and the roll-shaped transfer member 106.
In the contact area with the transfer member 106, the voltage applied between the intermediate transfer drum 110 and the transfer member 106 causes the transfer member 106 to move.
From the recording medium 112 to the recording material 112, the charge is electrostatically adsorbed on the charged recording material surface and is collectively transferred to the recording material 112 surface. The toner images collectively transferred to the surface of the recording material 112 are conveyed to the fixing device 107 and fixed by the fixing device 107.

FIG. 2 is a block diagram showing another embodiment of the image recording apparatus of the present invention. This image recording device
Drum-shaped photoreceptors 101K, 101Y, 101M, 101 having photosensitive layers on the surfaces corresponding to four colors of black (K), yellow (Y), magenta (M), and cyan (C)
Charging members 102K and 102Y that contact C and these photoconductors at a constant pressure and apply a DC voltage or a DC voltage superimposed on the AC between the photoconductors to uniformly charge the surface of the photoconductor. , 102M, 102C and image writing devices 104K, 104Y, 104 for forming electrostatic latent images by irradiating the uniformly charged photoconductors with image light, respectively.
Four developing units 105K, 105Y, 105M, 10 containing M, 104C and K, Y, M, C developers
5C and the four photoconductors 101K, 101Y, 101
Belt-shaped intermediate transfer member 11 that contacts M and 101C
0, a roller-shaped transfer member 106 for collectively transferring the toner images superposed and transferred onto the intermediate transfer member 110 onto the recording material 112 conveyed by the conveyance roller 109, and the recording material 112. A fixing device 107 for fixing the toner image is provided.

Each of the photoconductors 101K, 101Y, 101M,
An electrostatic latent image corresponding to each color is formed on 101C,
The developing devices 105K, 105Y, 105M, and 105C develop the toners of the respective colors to form toner images of the respective colors. Each photoconductor 101K, 101Y, 101M, 101C
Each of the upper color toner images is composed of two colors of the first intermediate transfer drum 11
0, and then the second intermediate transfer drum 111
The four colors are superimposed on top. Second intermediate transfer drum 11
The toner image on the transfer member 1 is transferred to the transfer member 1 by the voltage applied between the second intermediate transfer drum 111 and the transfer member 106.
The charge is transferred from 06 to the recording material 112, electrostatically adsorbed on the charged recording material surface, transferred to the recording material 112 all together, and then fixed on the recording material 112 by the fixing device 107.

FIG. 3 is a schematic view of an intermediate transfer drum used in the image recording apparatus shown in FIGS. 1 and 2. The intermediate transfer drum 110 according to the present embodiment includes the support member 2
03, a rubber elastic layer 202 is formed, and a surface layer 201 is further formed on the rubber elastic layer 202.

Next, each layer will be described. As the supporting member 203 of the intermediate transfer drum of the present invention, for example, stainless steel, iron plated or an aluminum shaft, a drum made by machining a cylindrical aluminum pipe to finish it, or a stainless plate bent into a cylindrical shape. It is possible to cite a seamless roll in which these joints are welded by laser processing.
The function required of the support member 3 is to support the semiconductive elastic layer 2 and the surface layer 1 and maintain a predetermined shape,
There is no limitation on the material and the processing method as long as the material is a conductive material that can be easily processed by machining such as lathe processing and polishing, and shaping processing such as drawing and drawing. The main function required of the semiconductive elastic layer 202 is to charge the surface layer 20 through the charges supplied through the supporting member 203.
1 required to form a stable contact area, that is, a nip area between the semi-conductive roller and a member that comes into contact with the semi-conductive roller, and a uniform nip width in the entire axial direction. It is the outer diameter uniformity required for forming.
The resistance of the intermediate transfer member of the present invention is 23 ° C. and the relative humidity is 55.
%, When measured by applying a direct current voltage of 1000 V, it is 10 ⁵ Ω or more and 10 ⁹ Ω or less. 10 ⁵
If it is smaller than Ω, an excessive current flows between the photosensitive member and the recording material, which causes deterioration of image quality. 10 ⁹ Ω
If it is larger, the potential difference between the photoconductor or the recording material becomes smaller, the transfer efficiency is lowered, and the image quality is lowered.

Usually, the semiconductive elastic body as described above has the property that the resistance decreases when the applied voltage during resistance measurement is increased. This is not preferable because it requires control. From such a point, 2 of the semiconductive roller is used.
3 ° C., R ₅₀₀ when the under 55% relative humidity environment, the roller resistance was measured by applying a DC voltage of 500V and 1000V and R _{50 0} and R ₁₀₀₀ respectively
When the value of / R ₁₀₀₀ is 0.8 or more and 1.2 or less, there is no problem in handling the member as a resistor having a constant resistance value, which is preferable in designing the control circuit.

Further, in order to obtain uniform image quality in various environments in which the electrophotographic apparatus is used, the roller resistance under the environment of 15 ° C. and 10% relative humidity, which are the lower limit of the temperature and humidity usually used. RLL and the same upper limit of 3
Roller resistance R under the environment of 2.5 ° C and relative humidity of 85%
If the ratio RLL / RHH of HH is 10 or less, it can be used as a constant resistor without using a special control mechanism. Furthermore, RL
When L / RHH is 5 or less, it may be used without using a special control mechanism even in an application such as a color printer in which particularly high quality images are required, which is preferable.

Because of these characteristics, the present invention
The conductive elastic layer is characterized by containing an inorganic metal salt and a polyoxyethylene compound as a conductivity imparting agent. As the inorganic metal salt used in the present invention, lithium,
Examples thereof include Group 1 metal salts of the periodic table such as sodium and potassium, and Group 2 metal salts of the periodic table such as Ca and Ba.

Examples of the above-mentioned Group 1 metal salts of the periodic table include LiCF ₃ SO ₃ , NaClO ₄ , LiClO ₄ , and L.
iAsF ₆ , LiBF ₄ , LiI, LiCl, LiB
Examples thereof include alkali metal salts such as r, NaSCN, KSCN, NaCl, NaI, and KI. Examples of the metal salt of Group 2 of the periodic table include Ca (ClO ₄ ) ₂ and Ba (ClO ₄ ) ₂ .

The polyoxyethylene compound of the present invention refers to one containing 50% or more of ethylene oxide units among the repeating units constituting the main chain, and conventionally known compounds are used without particular limitation. You can The number average molecular weight of the polyoxyethylene compound is 1
It is preferably less than 0000, more preferably less than 3000. When the number average molecular weight is 10,000 or more, it is not preferable from the viewpoints of fluidity and workability, and especially when the content of polyoxyethylene repeating units is high, the crystallinity of the compound becomes high, so that the phase in the semiconductive rubber is increased. There is concern that the melting balance may be lost. Specific examples of the polyoxyethylene compound include polyoxyethylene alkyl ether, polyoxyethylene alkenyl ether, polyoxyethylene alkylphenyl ether, polyoxyethylene polystyryl phenyl ether, polyoxyethylene-oxypropylene glycol, polyoxyethylene- Polyoxyethylene polyhydric alcohol fatty acid partial ester such as oxypropylene alkyl ether, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene glycerin fatty acid ester, polyoxyethylene fatty acid ester, polyoxyethylenated castor oil, polyoxyethylene alkylamine, poly Examples thereof include, but are not limited to, oxyethylene group-containing organopolysiloxane and crown ethers.

The inorganic metal salt and the polyoxyethylene compound may be added in an amount according to the roller resistance value to be set, but in order to improve the environmental stability of the roller, polyoxyethylene is added to the inorganic metal salt. It is preferable to add the ethylene compound in a molar ratio of 5 times or more, more preferably 10 times or more.

The semiconductive elastic layer used in the present invention is
(A) contains at least one alkenyl group in the molecule,
Curing containing a polymer whose main chain-constituting repeating units are mainly oxyalkylene units, (B) a curing agent containing at least two hydrosilyl groups in the molecule, and (C) a hydrosilylation catalyst It is preferable to use the reaction product of the volatile composition in that the inorganic metal salt and the oxyethylene compound are easily dissolved. Further, since this composition has low viscosity before curing and low hardness after curing, it is more preferable from the viewpoint of processability.

The polymer of the component (A) in this curable composition is a component which is cured by a hydrosilylation reaction with the component (B) and has at least one alkenyl group in the molecule, so that the hydrosilylation reaction To give a cured product. At least one alkenyl group in the component (A) is required, but in the case of a linear molecule, two alkenyl groups are present at both ends of the molecule, and in the case of a branched molecule, the molecular end When two or more alkenyl groups are present in, a cured product giving good rubber elasticity can be obtained.

Also from the viewpoint of reducing the hardness of the cured product, an oxyalkylene polymer in which the repeating unit is an oxyalkylene unit is preferable, and an oxypropylene polymer in which the repeating unit is an oxypropylene unit is further preferable. More preferable. That is, the curing composition described above,
It also has an advantage that a composition having an Asker C hardness of 60 degrees or less and a small compression set can be obtained without adding a plasticizer or the like that may adversely affect the photoreceptor.

Here, the oxyalkylene polymer means a polymer in which 30% or more, preferably 50% or more of the units constituting the main chain consist of oxyalkylene units, and it is contained in addition to the oxyalkylene units. Examples of the unit include a unit used as a starting material at the time of polymer production and having a compound having two or more active hydrogens, for example, a unit derived from ethylene glycol, a bisphenol compound, glycerin, trimethylolpropane, pentaerythritol, or the like. . In the case of the oxypropylene polymer, it may be a copolymer (including a graft polymer) with a unit composed of ethylene oxide, butylene oxide or the like.

The molecular weight of the oxyalkylene polymer as the component (A) as described above is a number average molecular weight (Mn) from the viewpoint of improving the balance between reactivity and low hardness.
It is preferably from 5,000 to 40,000. When the number average molecular weight is less than 5,000, it becomes difficult to obtain sufficient mechanical properties (rubber hardness, elongation rate) and the like when the curable composition is cured. On the other hand, if the number average molecular weight is too high, the viscosity tends to be too high and the processability tends to be poor.

One of the characteristics of this curable composition is that
This is because it is easy to produce a product having a low hardness, and in order to exert this characteristic, it is preferable that the number of alkenyl groups is 2 or more at the terminal of the molecule, and the number of alkenyl groups becomes larger than the molecular weight of the component (A). If it is too large, it becomes rigid and it becomes difficult to obtain good rubber elasticity.

The component (B) in the curable composition is not particularly limited as long as it is a compound having at least two hydrosilyl groups in the molecule, but the number of hydrosilyl groups contained in the molecule is too large. And after curing, a large amount of hydrosilyl groups are likely to remain in the cured product, causing voids and cracks. If the number of hydrosilyl groups is too small, there is a problem in curability, so it is 2 to 40. It is preferable. In the present invention, having one hydrosilyl group means having one H bonded to Si, S
In the case of iH ₂ , it has _two hydrosilyl groups, but H bonded to Si is preferably bonded to different Si because the curability is better and rubber elasticity is also preferable. The amount of the curing agent (B) added is such that the silicon atom-bonded hydrogen atoms of the curing agent (B) are 0.8 to 5.0 equivalents based on the total amount of the alkenyl groups of the polymer (A). It is preferable. When the amount of silicon atom-bonded hydrogen atoms in the curing agent (B) is less than 0.8 equivalent to the total amount of alkenyl groups in the polymer (A), the crosslinking becomes insufficient, and when it exceeds 5.0 equivalents, The physical properties tend to change significantly due to the effects of silicon-bonded hydrogen atoms remaining after curing.

As the hydrosilylation catalyst which is the component (C)
Are those that can be used as hydrosilylation catalysts.
As long as there is no limit. For platinum, alumina, etc.
Solid platinum supported, chloroplatinic acid (alcohol
(Including any complex), various platinum complexes, rhodium, rutheni
Chromium of metals such as um, iron, aluminum and titanium
Which can be mentioned. The amount of hydrosilylation catalyst (C) added
Is not particularly limited, but is not limited to 1 alkenyl group of the polymer (A).
10 against Le^-1-10^-8Preferably used in the molar range
Really 10 ^-2-10^-6More preferred to use in the molar range
Good Also, hydroxylation catalysts are generally expensive and corrosive.
It also has the property of generating a large amount of hydrogen gas and producing a cured product.
10 because it may foam^-1Use more than mol
Is not preferable.

In addition to the components (A) to (C) described above, the curable composition also includes a storage stability improving agent such as a compound having an aliphatic unsaturated bond, an organic phosphorus compound, an organic sulfur compound, A nitrogen-containing compound, a tin compound, an organic peroxide, etc. may be added. Specific examples thereof include, for example, benzothiazole, thiazole, dimethylmalate, dimethylacetylene carbochelate,
Examples include, but are not limited to, 2-pentenenitrile, 2,3-dichloropropene, quinoline, and the like. Among these, thiazole and dimethyl maleate are particularly preferable from the viewpoint of compatibility between pot life and rapid curing property. The storage stability improvers may be used alone or in combination of two or more.

Further, a filler, a storage stabilizer, a plasticizer, an ultraviolet absorber, a lubricant, a pigment and the like may be added to the curable composition in order to improve processability and cost.

By injecting a curable composition into a mold having the above-mentioned shaft installed in the center by casting, injection, extrusion molding, or the like, and heating and curing at a suitable temperature and time,
A conductive elastic layer can be formed around the shaft. From the conductive elastic layer, the resin constituting the surface layer is applied to a predetermined thickness by a method such as spray coating, dip coating, or roll coating, and then dried and cured at a predetermined temperature to obtain the present invention. The semi-conductive roller of is obtained. The main component of the surface layer is not particularly limited, but it is preferable to contain a —NHCO— bond from the viewpoint of conductive properties, and in terms of hydrolysis resistance, ozone resistance, environmental stability, etc. Polyurethanes represented by ether urethane or polycarbonate urethane are particularly preferable. The polyether urethane is a compound obtained by reacting a polyether polyol and a polyisocyanate, and the polyether polyol is not particularly limited, but polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and polyethylene oxide-polypropylene. An oxide copolymer etc. are mentioned.

The polycarbonate urethane is
It is a compound obtained by the reaction of a polycarbonate polyol and a polyisocyanate. The polycarbonate polyol is not particularly limited, but it is obtained by condensation of a polyhydric alcohol and phosgene, chloroformate, dialkyl carbonate or diallyl carbonate. Examples of the polyhydric alcohol include 1,6-hexanediol, 1,4-butanediol, 1,3-butanediol, and 1,5-pentanediol.

Examples of the polyisocyanates include tolylene diisocyanate (TDI), 4,4'-diophenylmethane diisocyanate (MDI), xylene diisocyanate (XDI), hexamethylene diisocyanate (HDI), hydrogenated MDI and hydrogenated TDI. Alternatively, isophorone diisocyanate (IPDI) or the like is used. Among these, hydrogenated MDI or IPDI is preferably used in consideration of the balance of properties such as availability, cost, electrical characteristics, and mechanical characteristics.

From the viewpoint of resistance adjustment, surface shape adjustment, adhesion to the conductive elastic layer, etc., the coating layer is
You may add various additives, such as a conductive agent, various fillers, or a silane coupling agent as needed. The method of applying the coating layer is not particularly limited, but for example, a method of dissolving the above resin in a solvent to make the solid content 5 to 15% and spraying or dipping it is convenient. At this time, various additives such as a leveling agent may be added as necessary in order to improve the coating property of the coating layer solution.

The thickness of the surface layer is set to an appropriate value depending on the material, composition and application used and is not particularly limited, but usually 5 μm or more and 50 μm or less is preferable. If the thickness is less than 5 μm, the wear resistance tends to decrease and the long-term durability tends to decrease. When it is thicker than 50 μm, there is a tendency that problems such as wrinkles easily occur and compression strain increases due to the difference in linear expansion coefficient with the elastic layer. The thickness of the semiconductive elastic layer is to be appropriately set according to the intended use and the like, and is not particularly limited, but usually 1 mm or more and 10 mm or less is preferable. If the elastic layer is thinner than 1 mm, it is difficult to secure a sufficient contact width even if the hardness of the semiconductive elastic layer is low, and if it is thicker than 10 mm, undesired deformation such as twisting tends to occur during use. It easily causes image defects.

[0036]

EXAMPLES The present invention will be described below with reference to specific examples. In these examples and comparative examples, the length is 248 m.
An aluminum sleeve having an outer diameter of 32 mm and an outer diameter of 32 mm was subjected to a primer treatment and used as a supporting member. (Example 1) (A) Allyl-terminated polyoxypropylene (trade name: Kaneka Cyryl ACX004-N, manufactured by Kanegafuchi Chemical Industry): 100
Based on parts by weight, (B) polyorganohydrogen siloxane (trade name ACX-004-C, manufactured by Kanebuchi Chemical Industry Co., Ltd.): 6.6 parts by weight, (C) bis (1,3-divinyl-)
1,1,3,3-Tetramethyldisiloxane) platinum complex catalyst (platinum content 3 wt%, xylene solution): 0.06
By weight, and as a conductivity-imparting agent, lithium chloride:
0.05 parts by weight and 5 parts by weight of a nonionic surfactant (trade name Nonion E205S, manufactured by NOF CORPORATION) as an oxyethylene-based compound were mixed and degassed under reduced pressure (10 mmHg or less, 120 minutes). After pouring the obtained composition into the mold in which the shaft is installed, the mold is heated to 140 ° C.
By heating for 30 minutes at 30 ° C. to cure the composition, a semiconductive elastic body layer having a thickness of about 5 mm was formed on the outer circumference of the shaft. Next, on the surface of the semiconductive elastic layer, polyether urethane (trade name Y258, manufactured by Dainichiseika) was diluted with methyl ethyl ketone / dimethylformamide = 1/1 to a solid content of 5%, and carbon black was used as a conductive agent. (MA220, manufactured by Mitsubishi Kagaku Co., Ltd.) is 10 with
A solution in which parts by weight are dispersed is prepared, and the surface of the semiconductive elastic layer is sprayed and dried (160 ° C., 30 minutes) to form a coating layer of 10 μm on the outer peripheral surface of the semiconductive elastic layer. A sex roller was produced.

The semiconductive roller produced as described above was left standing for 24 hours in an environment of 23 ° C. and 55% relative humidity (hereinafter also referred to as 55% Rh), and then the following measurements were performed in this environment. In order to investigate the resistance change due to the applied voltage of this roller, put the roller on an aluminum plate for 1 kg.
Under a load of 1 (that is, a state where a load of 1 kg was applied to the entire roller), DC voltages of 500 V and 1000 V were applied between the aluminum plate and the shaft, and R ₅₀₀ and R ₁₀₀₀ were measured. As a result, R ₅₀₀ is 2.5 × 10 ⁷ Ω, R
₁₀₀₀ was 2.4 × 10 ⁷ Ω and R ₅₀₀ / R ₁₀₀₀ was 1.04.

Next, in order to measure the environmental dependence of the roller resistance, the roller was placed in an environment of 15 ° C. and a relative humidity of 15% (LL) and 24 in an environment of 32.5 ° C. and a relative humidity of 85% (HH). After leaving for a while, continue to put the roller on the aluminum plate in each environment for 1K
1000 g between the aluminum plate and the shaft under a load of g
Roller resistance RLL and RHH while applying DC voltage of V
Was measured. As a result, RLL and RHH are 5.0 × 10 ⁷ Ω
(RLL) and 1.0 × 10 ⁷ Ω (RHH),
/ RHH was 5.0. (Example 2) (A) Allyl-terminated polyoxypropylene (trade name: Kaneka Cyryl ACX004-N, manufactured by Kanegafuchi Chemical Industry): 100
Based on parts by weight, (B) polyorganohydrogen siloxane (trade name ACX-004-C, manufactured by Kanebuchi Chemical Industry Co., Ltd.): 6.6 parts by weight, (C) bis (1,3-divinyl-)
1,1,3,3-Tetramethyldisiloxane) platinum complex catalyst (platinum content 3 wt%, xylene solution): 0.06
Parts by weight, and lithium perchlorate as a conductivity-imparting agent:
0.07 parts by weight and 5 parts by weight of a nonionic surfactant (trade name: Uniox MM500, manufactured by NOF CORPORATION) as an oxyethylene compound were mixed, and decompression (10 mmHg or less,
It was degassed for 120 minutes. After pouring the obtained composition into the mold having the shaft, the whole mold is heated at 140 ° C. for 3 hours.
By heating for 0 minutes to cure the composition, a rubber elastic body layer having a thickness of about 5 mm was formed on the outer circumference of the shaft.
Next, on the surface of the semiconductive elastic layer, polyether urethane (trade name Y258, manufactured by Dainichiseika) was diluted with methyl ethyl ketone / dimethylformamide = 1/1 to a solid content of 5%, and carbon black was used as a conductive agent. (MA
220, manufactured by Mitsubishi Chemical Co., Ltd.) was prepared by dispersing 10 parts by weight of the resin solid content in a solution, and the solution was applied to the surface of the semiconductive elastic layer by spraying and dried (160 ° C., 30 minutes) to obtain a semiconductive elastic layer. A 10 μm-thick coating layer was formed on the outer peripheral surface to prepare a semiconductive roller. Next, when the R ₅₀₀ and R ₁₀₀₀ of this roller were measured by the same method as in Example 1,
R ₅₀₀ is 2.0 × 10 ⁷ Ω, R ₁₀₀₀ is 1.9 × 10 ⁷ Ω,
R ₅₀₀ / R ₁₀₀₀ was 1.05. Next, the roller resistances RLL and RHH were measured in the same manner as in Example 1, and were 3.6 × 10 ⁷ Ω (RLL) and 8.0 × 10 ⁶ Ω.
(RHH), and RLL / RHH was 4.5. (Comparative Example) (A) Allyl-terminated polyoxypropylene (trade name: Kaneka Cyryl ACX004-N, manufactured by Kaneka Corporation): 100
Based on parts by weight, (B) polyorganohydrogen siloxane (trade name ACX-004-C, manufactured by Kanebuchi Chemical Industry Co., Ltd.): 6.6 parts by weight, (C) bis (1,3-divinyl-)
1,1,3,3-Tetramethyldisiloxane) platinum complex catalyst (platinum content 3 wt%, xylene solution): 0.06
Parts by weight, and lithium chloride as a conductivity-imparting agent 0.0
5 parts by weight were mixed and defoamed under reduced pressure (10 mmHg or less, 120 minutes). After pouring the obtained composition into the mold in which the shaft is installed, and heating the mold together at 140 ° C. for 30 minutes to cure the composition, the rubber elasticity of about 5 mm on the outer circumference of the shaft is obtained. A body layer was formed. Next, on the surface of the semi-conductive elastic layer, polyether urethane (trade name Y
258, manufactured by Dainichi Seika) was diluted with methyl ethyl ketone / dimethylformamide = 1/1 to a solid content of 5%, and carbon black (MA220, manufactured by Mitsubishi Chemical) as a conductive agent was added to the resin solid content in an amount of 10 parts by weight. A dispersed solution is prepared, and applied to the surface of the semiconductive elastic layer by spraying and dried (160 ° C., 30 minutes) to form a coating layer of 10 μm on the outer peripheral surface of the semiconductive elastic layer. Was produced. Next, R ₅₀₀ and R ₁₀₀₀ of this roller were measured by the same method as in Example 1. As a result, R ₅₀₀ was 3.0 × 10 ⁷ Ω, R ₁₀₀₀ was 2.8 × 10 ⁷ Ω, R ₅₀₀
/ R ₁₀₀₀ was 1.07. Next, RL of roller resistance
When L and RHH were measured by the same method as in Example 1,
5.0 × 10 ⁸ Ω (RLL) and 1.0 × 10 ⁷ Ω (RH
H) and RLL / RHH was 50. Next, in order to evaluate the transfer characteristics (residual toner amount, transfer unevenness, and image voids) of the intermediate transfer drums manufactured in Examples 1 and 2, and Comparative Example, the intermediate transfer type laser beam printer shown in FIG. It was mounted as an intermediate transfer drum, and an image was output under each environment using spherical toners of four colors of cyan (C), magenta (M), yellow (Y), and black (K) having an average particle size of 6 μm, and evaluated. For the evaluation, line drawing, halftone image, and character image were used with toners of four colors of C, M, Y, and K, LL (15 ° C., 10% Rh), NN (23 ° C.,
It was performed by outputting under each environment of 55% Rh) and HH (32.5 ° C., 85% Rh) and comparing the image quality such as color unevenness and image blurring. As a result, when the intermediate transfer drums produced in Examples 1 and 2 were used, good image quality was obtained for all line images, halftone images, and character images, and no difference was observed between the four color toners. Also, L
A good image was obtained with very little difference in image quality between the L, NN, and HH environments. On the other hand, when the intermediate transfer drum manufactured in the comparative example was used, color unevenness was observed in the halftone image, and a difference in hue was observed in each environment of LL, NN, and HH.

[0039]

As described above, in the image recording apparatus using the intermediate transfer member for electrophotography according to the present invention, the fluctuation of the image quality due to the environment in which it is used is extremely small and a high quality image can be obtained.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of an image recording apparatus using an electrophotographic intermediate transfer member of the present invention.

FIG. 2 is a configuration diagram of another embodiment of an image recording apparatus using the electrophotographic intermediate transfer member of the present invention.

FIG. 3 is a schematic view of an intermediate transfer drum of the present invention used in the image recording apparatus shown in FIGS.

[Explanation of symbols]

101, 101K, 101Y, 101M, 101C Photoconductors 1, 102K, 102Y, 102M, 102C Charging roller 103 Cleaning devices 104a, 104K, 104, 104M, 104C Writing device 104b Writing exposure light 105a, 105b, 105c, 105d, 105K,
105, 105M, 105C Developing device 106 Transfer member 107 Fixing device 108 Eliminating lamp 109 Conveying rolls 110, 111 Intermediate transfer drum 112 Recording material 201 Surface layer 202 Rubber elastic layer 203 Supporting member

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 2H200 FA01 GA23 JC02 JC13 JC15                       JC16 LC04 MA01 MA03 MA13                       MA20 MB02 MB06 MC01

Claims (4)

[Claims] 1. A semiconductive roller comprising a metal supporting member, a semiconductive elastic layer formed on the outer peripheral surface of the supporting member, and a coating layer formed on the outer peripheral surface of at least one layer. Wherein the semiconductive elastic layer contains an inorganic metal salt and a polyoxyethylene compound as a conductivity-imparting agent. 2. The semiconductive roller is (1) to (3).
The electrophotographic intermediate transfer member according to claim 1, having the following characteristics. (1) 10 in an environment of 23 ° C. and 55% relative humidity
The roller resistance measured by applying a DC voltage of 00V is 1
It is not less than 0 ⁵ Ω and not more than 10 ⁹ Ω. (2) 50% in an environment of 23 ° C and 55% relative humidity
When the roller resistance measured by applying a DC voltage of 0 V and 1000 V is R ₅₀₀ and R ₁₀₀₀ , the value of R ₅₀₀ / R ₁₀₀₀ is 0.8 or more and 1.2 or less. (3) Roller resistance RLL measured by applying a DC voltage of 1000 V in an environment of 15 ° C. and 10% relative humidity, and 3
Ratio RLL / R of roller resistance RHH measured by applying a DC voltage of 1000 V in an environment of 2.5 ° C. and relative humidity of 85%
HH is 10 or less. 3. The semiconductive elastic layer has at least one alkenyl group in the molecule (A),
Polymer (B) whose repeating unit constituting the main chain is an oxyalkylene unit (C) Curing agent having two or more hydrosilyl groups in the molecule (C) Reaction of electrically conductive curable composition containing hydrosilylation catalyst as a main component The electrophotographic intermediate transfer member according to claim 1 or 2, wherein the intermediate transfer member comprises an object. 4. The inorganic metal salt comprises an inorganic salt of at least one metal selected from the metals of Group 1 and the metals of Group 2 of the Periodic Table. 1
The intermediate transfer member for electrophotography according to any one of items 1 to 3.