JPH05107794A - Semiconductive transfer roller and production thereof - Google Patents

Abstract

PURPOSE:To obtain the semiconductive transfer roller which has a large electrostatic capacity and good transfer efficiency, exhibits uniform volumetric resistance, has excellent characteristics, such as freedom from generation of leak currents, and is adequate for the reduction of weight and speeding up of electrophotographic copying machines and electrostatic recorders, such as laser printers and facsimiles. CONSTITUTION:This semiconductive transfer roller is constituted by successively laminating a conductive elastic material layer (A) having <=10<7>OMEGAcm specific volume resistance, a conductive resin layer (B) having <=10<5>OMEGAcm specific volume resistance and <=100 deg.C m.p., and a semiconductive resin layer (C) which has 10<8> to 10<12>OMEGAcm specific volume resistance and >=50mum thickness and is constituted of a mixture composed of 15 to 70wt.% polyvinylidene fluoride, 30 to 95wt.% fluororubber, and 3 to 15wt.% charge control material on the outer periphery of a revolving shaft. This roller is constituted by fitting a cylindrical tube consisting of the (B) layer as the inner layer and the (C) layer as the outer layer onto the revolving shaft coated with the (A) layer and heating the roller to <=150 deg.C.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductive transfer roller suitable for reducing the weight and increasing the speed of electrostatic recording devices such as electrophotographic copying machines, laser printers and facsimiles, and a method for manufacturing the same.

[0002]

2. Description of the Related Art Electrostatic recording devices such as electrophotographic copying machines, laser printers and facsimiles normally form an electrostatic latent image on the surface of a charged photoreceptor by light or other means and attach it to the electrostatic latent image. A mechanism for transferring and fixing the formed toner image onto recording paper by using electrostatic force is employed. The electrostatic transfer method includes corona transfer method, belt transfer method, roller transfer method, etc.
Among them, the most commonly used corona transfer method is one in which a recording paper is superposed on a toner image and a charge having a polarity opposite to that of the toner is applied from a back side of the recording paper by a corona charger to transfer. This method has an advantage that the recording paper is easy to convey because the recording paper and the corona charger are not in contact with each other, but harmful ozone is generated, and the adhesion between the photoconductor and the recording paper is poor. Then, there was a defect that spot-like white spots sometimes occurred. Further, when the electric resistance of the recording paper becomes less than 10 ⁸ Ωcm at high humidity, the charge on the recording paper leaks to the ground side to cause transfer failure, or conversely, when the electric resistance of the recording paper becomes 10 ¹³ Ωcm or more. There is a problem that toner is likely to be scattered when the recording paper is separated.

The belt transfer method includes a conductive belt transfer method and a dielectric belt transfer method. Among them, the dielectric belt transfer method uses a belt in which the back surface of an endless dielectric film is conductively treated, the surface of this dielectric film is charged by a corona charger, etc., and the recording paper is electrostatically adsorbed by this electrostatic charge, In this method, the recording paper is conveyed to the transfer area, and in the transfer area, the toner is transferred to the recording paper by this charged electric charge to perform the transfer. This method has advantages such as transfer and paper conveyance with a simple structure, but has a problem that there is a limit to downsizing the apparatus.

In the roller transfer method, the transfer is performed by directly pressing the recording paper and the photoconductor with a roller, so that the recording paper and the surface of the photoconductor are in close contact with each other and a transfer image of higher quality can be obtained as compared with the corona transfer method. It has the features that it can be transferred, and that it is less affected by the decrease in the electrical resistance of the recording paper under high humidity than the corona transfer method. Among the roller transfer methods, a conductive roller using conductive rubber or the like is generally used because of its simple device configuration. However,
In this case, there are problems that it is difficult to obtain a conductive roller having a smooth surface, and a short circuit easily occurs between the photoconductor and the conductive roller. On the other hand, the transfer roller provided with a dielectric layer on the conductive rubber is not only effective in preventing a short circuit between the photoconductor and the transfer roller, but the dielectric layer made of synthetic resin also uses a rubber surface for smoothness. It has the advantage that it is superior to the case where it has a specific volume resistance of 10 ⁸ to 10 ¹² Ω on the conductive rubber.
In addition to the above advantages, the semiconductive transfer roller provided with the semiconductive layer in the range of cm has an excellent performance that the charging time is short and there is no need for static elimination after transfer.

However, the semiconductive transfer roller having such excellent performance has various problems for industrial use. That is, a charge having a polarity opposite to that of the charged toner is applied to the semiconductive layer, and this charge generates an electric field between the recording paper and the toner layer to transfer the charged toner from the surface of the photoconductor to the recording paper. It is said that the higher the electric field is increased or the electrostatic capacity of the semiconductive layer is increased, the higher the electric field and the higher the transfer efficiency and the better the transferred image can be obtained. However, if the applied voltage is too high, there is a problem that discharge occurs. In order to increase the capacitance of the semiconductive layer, there are methods such as reducing the thickness of the semiconductive layer and using a resin having a high dielectric constant for the semiconductive layer. Moreover, it is not only difficult to form a semi-conductive synthetic resin film having a uniform thickness, but there is also a problem that if the thickness is made too thin, electric charges leak to the ground side.

Polyvinylidene fluoride resin is known as a resin having a high dielectric constant. When a conductive film is mixed with this polyvinylidene fluoride resin to form a cylindrical film and it is used as the semiconductive layer of a semiconductive roller, the hardness of the polyvinylidene fluoride resin is high and the obtained roller is There is a problem that the surface hardness becomes too high and a good transferred image cannot be obtained. In addition, when an ordinary conductive material is used to impart semiconductivity, the volume resistivity decreases significantly with an increase in the added amount, and it is difficult to finely adjust the volume resistivity value to the target value. Met. Further, since such a conductive material is difficult to mix uniformly in the polyvinylidene fluoride resin, some parts may have a low volume resistivity and short-circuit may occur between that part and the photoconductor.

Therefore, when the transfer using the semi-conductive roller is practically used, the electrostatic capacity is 150 p.
Provided is a semiconductive synthetic resin film having a uniform thickness of more than F / cm ² , particularly a cylindrical semiconductive film having a uniform inner diameter. The volume resistivity does not vary and can be accurately controlled, the transfer roller has appropriate elasticity and surface hardness in order to maintain a uniform transfer pressure and obtain a good transferred image, and adheres to the surface of the transfer roller. It has been demanded to solve the problem that the toner has good cleaning property.

[0008]

The present invention is suitable for reducing the weight and increasing the speed of electrostatic recording devices such as electrophotographic copying machines, laser printers, and facsimiles, which solve the above problems and give good transferred images. It is an object of the present invention to provide a semiconductive transfer roller having excellent properties and a method for manufacturing the same.

[0009]

According to the present invention, in a transfer roller for transferring a toner image adhered to an electrostatic latent image on a photoconductor to a recording sheet by electrostatic force, the transfer roller is a rotary shaft. A conductive elastic layer (A) having a volume resistivity of 10 ⁷ Ωcm or less on the outer periphery of the, and a volume resistivity of 10 ⁵ Ωc
a conductive resin layer (B) having a melting point of 100 ° C. or less,
And a semiconductive resin layer (C) having a volume resistivity in the range of 10 ⁸ to 10 ¹² Ωcm, and the semiconductive resin layer (C) has a thickness of 50 μm or more and 100 μm or less. A semiconductive transfer roller comprising a mixture of 15 to 67 wt% of polyvinylidene fluoride resin, 30 to 82 wt% of fluororubber, and 3 to 15 wt% of antistatic substance is provided. The semiconductive transfer roller is provided in which the electrically conductive material is polyether ester amide or polyether amide, and the conductive resin layer (B) is a vinyl chloride graft ethylene / vinyl acetate copolymer. The semiconductive transfer roller is provided, and the semiconductive transfer layer is characterized in that the conductive elastic layer (A) has a JIS-A surface hardness of 25 to 35. B Is provided, and the inner layer has a volume resistivity of 1 on the rotating shaft coated with the conductive elastic layer (A) and having a volume resistivity of 10 ⁷ Ωcm or less.
0 ⁵ [Omega] cm or less, a melting point of 100 ° C. or less of the conductive resin layer (B), a semi-conductive resin layer ranging volume resistivity 10 ⁸ ~10 ¹² Ωcm (C) is cylindrical is the outer layer The tube is fitted and heated to a temperature of 150 ° C. or lower to melt the conductive resin layer (B), and thus the conductive elastic body layer (A), the conductive resin layer (B) and the semi-conductive layer. A method for manufacturing the semiconductive transfer roller is provided, which comprises adhering a conductive resin layer (C).

That is, in the semiconductive transfer roller of the present invention, since the semiconductive resin layer on the roller surface is composed of polyvinylidene fluoride resin and fluorine rubber having a high dielectric constant and good workability, a high electrostatic property is obtained. A cylindrical film having a uniform inner diameter and thickness that forms a semiconductive resin layer having a capacity can be easily obtained. The surface hardness of the obtained transfer roller is not too high, and the transfer roller can be transferred with an appropriate transfer pressure and can be easily removed and cleaned even if the transfer roller is soiled due to toner scattering. When a polyether amide or a polyether ester amide is used as the antistatic substance, the semiconductive layer having a uniform electric resistance can be obtained because the miscibility and compatibility of the antistatic substance with the resin are good. Not only can the volume resistivity value be accurately controlled.

Further, when the semiconductive transfer roller is manufactured by the manufacturing method of the present invention, the conductive elastic body layer (A), the conductive resin layer (B) and the semiconductive resin layer (C) adhere to each other. The resulting semiconductive transfer roller can be prevented from slipping due to delamination during rotation, and the temperature required for bonding can be low, so that the shape of the transfer roller is not deformed.

The present invention will be specifically described below. First,
The volume resistivity which is the innermost layer of the transfer roller of the present invention is 10
^The conductive elastic layer (A) having a resistance of ⁷ Ωcm or less is obtained by adding and mixing known conductive materials such as carbon black and metal fine particles to elastic materials such as polyurethane resin, silicone resin, chloroprene rubber, nitrile rubber, and EPDM. A material having a volume resistivity of 10 ⁷ Ωcm or less is used. In particular, in order to obtain a proper transfer pressure, the hardness of the conductive elastic layer (A) is preferably about 25 to 35 (JIS-A hardness), and the hardness of the semiconductive resin layer (C) on the surface is Since it is considerably higher than that, it is usually preferable to use a foamed polyurethane resin or the like obtained by further foaming the elastic material.

The conductive resin layer (B) having a volume resistivity of 10 ⁵ Ωcm or less and a melting point of 100 ° C. or less, which is an intermediate layer of the transfer roller of the present invention, is, for example, a vinyl chloride graft ethylene / vinyl acetate copolymer, A thermoplastic resin composed of one or more selected from the group consisting of chlorinated polyethylene, polyurethane resin, polyetheramide copolymer, polyetherester copolymer, etc., and carbon black and metal fine particles, which are known conductive materials. A material whose volume resistivity is adjusted to 10 ⁵ Ωcm or less by adding and mixing the above is used, but in particular, its melting point is low at around 50 ° C., its adhesiveness and compatibility with conductive materials are good, and it is extruded. Most preferably, a conductive material is mixed with vinyl chloride-grafted ethylene / vinyl acetate copolymer, which can easily obtain a film of uniform thickness by molding. Yes.

Conductive resin layer (B) having a melting point of 100 ° C. or less
When the semiconductive resin layer (C) is directly laminated on the conductive elastic body layer (A) directly on the rotating shaft without thermal contact, the semiconductive resin layer (C) has a considerably high melting point. Since it is expensive and contains a fluorine-based synthetic resin as a main component, the adhesiveness is poor and it is difficult. Further, the transfer roller obtained when the conductive elastic layer (A) and the semiconductive resin layer (C) are bonded together by using a liquid or semisolid conductive adhesive has a constant roller diameter. Can't get In the present invention, the conductive resin layer (B)
In addition, since a resin having a melting point of 100 ° C. or less is used, the conductive elastic body layer (A), the conductive resin layer (B), and the semi-conductive resin are used even if the ambient temperature is a relatively low temperature of 150 ° C. or less. The layers (C) are in close contact with each other, and a transfer roller can be obtained without slipping due to delamination during rotation or deformation during heat fusion.

The semiconductive resin layer (C) is made of polyvinylidene fluoride resin 15 to 67 wt% and fluororubber 30 to 82 wt%.
And a mixture of 3 to 15 wt% of antistatic material.
Since polyvinylidene fluoride resin has a high dielectric constant, a transfer roller having a large electrostatic capacity and a high transfer efficiency can be obtained, and the surface releasability is good, so that it can be adhered by scattering and the toner can be completely removed. Has a Young's modulus of 6,000
It is as high as around kg / cm ^2, and if used alone as it is, the hardness of the entire transfer roller becomes too high, which is not preferable.
Therefore, in the present invention, a fluororubber having a good compatibility with the polyvinylidene fluoride resin and a high dielectric constant is mixed and used. The amount of polyvinylidene fluoride resin is 67 wt%
If the amount exceeds 80%, the hardness of the semiconductive resin layer (C) increases, and the hardness of the entire transfer roller increases accordingly, which is not preferable. .. Examples of the type of fluororubber used include vinylidene fluoride-hexafluoropropene copolymer and vinylidene fluoride-propylene copolymer. The semiconductive resin layer (C) obtained with the above composition has a characteristic that the surface has good smoothness.

In the present invention, the volume resistivity of the semiconductive resin layer (C) is adjusted within the range of 10 ⁸ to 10 ¹² Ωcm. The volume resistivity of the semiconductive resin layer (C) is 1
If it is less than 0 ⁸ Ωcm, the electric charge may leak, which is not preferable. On the contrary, if the volume resistivity exceeds 10 ¹² Ωcm, it is difficult to remove the toner by adhering to the transfer roller due to scattering. This is not preferable because it requires static elimination.

In order to impart semiconductivity to such a mixture of polyvinylidene fluoride resin and fluororubber, 3 to 15 wt% of an antistatic substance is further used. A known conductive material may be used as the antistatic substance, but the volume resistivity of the semiconductive resin layer (C) can be accurately controlled within the range of 10 ⁸ to 10 ¹² Ωcm, and the above resin composition can be used. It is preferable to use a polyether amide or a polyether ester amide which is excellent in compatibility with and dispersibility and is capable of obtaining a uniform semiconductive resin layer (C). Furthermore, an organic electrolyte is added to these as an antistatic substance. It is preferable to add 0.1 to 1.0 wt% of the total composition. The transfer roller of the present invention made of such a resin composition has a small range of change in resistance due to a change in humidity,
Compared with the conventional corona discharge method of directly charging the recording paper, there are few transfer defects such as white spots, and it is easy to remove the charges.

In the present invention, the polyether ester amide is a block copolymer composed of a polyamide block unit such as nylon 6, 66, 11 or 12 and a polyether ester unit, and is a lactam having 6 or more carbon atoms or an aminocarboxylic acid. It means a copolymer derived from an acid salt (a), polyethylene glycol (b) and a dicarboxylic acid having 4 to 20 carbon atoms, for example, dicarboxylic acid (c) such as terephthalic acid, isophthalic acid and adipic acid.

The polyether amide is a block copolymer composed of a polyamide block unit such as nylon 6, 66, 11 or 12 and a polyether unit,
It essentially means a copolymer containing polyethylene glycol diamine, a dicarboxylic acid, an aliphatic diamine, and ε-caprolactam as main components.

The organic electrolyte is formed from dodecylbenzenesulfonic acid, tridecylbenzenesulfonic acid, nonylbenzenesulfonic acid, hexadecylbenzenesulfonic acid, dodecylsulfonic acid, or another sulfonic acid and an alkali metal such as sodium, potassium or lithium. There are alkali metal salts of sulfonic acid, alkali metal salts of phosphoric acid such as sodium distearylphosphate, and other alkali metal salts of organic carboxylic acid, and metal salts of sulfonic acid such as sodium dodecyl sulfonate are particularly preferable.

Further, in the present invention, it is necessary that the thickness of the semiconductive resin layer (C) is 50 μm or more and 100 μm or less. Generally, in order to improve the transfer efficiency, the thickness of the semi-conductive resin layer should be reduced so that the capacitance is at least 150p.
Although it is required to be F / cm ² or more, in the present invention, since polyvinylidene fluoride resin having a high dielectric constant and fluororubber are used, the thickness can be reduced to less than 50 μ to reduce the capacitance. No need to increase. Therefore, the thickness of the semi-conductive resin layer (C) is thin, so that there is no fear of leakage of electric charges. Further, if the thickness exceeds 100 μ, the surface hardness of the roller becomes too high and a good transferred image cannot be obtained even if the hardness of the conductive elastic layer (A) is lowered, which is not preferable.

As an example of the method for producing the semiconductive transfer roller of the present invention, polyvinylidene fluoride resin, fluororubber, antistatic substance and organic electrolyte are melted by an extruder and extruded into a cylindrical shape from an annular die, A tube used as the semiconductive resin layer (C) is obtained. Also, a composition obtained by adding carbon black as a conductive material to a vinyl chloride graft ethylene / vinyl acetate copolymer is extrusion-molded to obtain a film used as the conductive resin layer (B). This conductive film may be formed into a cylindrical shape by heat-sealing the film, or may be formed into a cylindrical shape from the beginning by an inflation extrusion molding method. Then, a cylindrical metal drum is covered with a cylindrical film used as the conductive resin layer (B) and a tube used as the semiconductive resin layer (C) in this order, and the melting point of the vinyl chloride graft ethylene / vinyl acetate copolymer is covered. The above is heat-fused to form a laminated tube. Subsequently, the obtained laminated tube was fitted onto a conductive elastic roller having a foamed polyurethane elastic body having a volume resistivity value of 10 ⁷ Ωcm or less formed on the outer side of a metal rotating shaft, and heat fusion was again performed at 150 ° C. or less. Thus, the transfer roller of the present invention is obtained.

[0023]

EXAMPLES The present invention will be described in detail below with reference to examples. Production Example 1 Stainless steel metal core (diameter 6 mm, length 30 c
After applying a urethane-based adhesive to m), a sheet of conductive polyurethane foam having carbon black added at 20 wt% and having different hardnesses is wound around the outer periphery of the metal core body, put into a metal mold and pressurized. Molded into rollers.
The outer circumference of the obtained roll is ground to a diameter of 18.55 m.
A conductive roller having a m and a surface length of 26 cm was obtained. The JIS-A hardness of the obtained conductive roller was 30 and 40, respectively, and the volume resistivity was 10 ⁴ Ωcm.

Production Example 2 Polyvinylidene fluoride resin (manufactured by Mitsubishi Yuka Co., Ltd., KYNA)
R2812) 22.75 wt%, fluororubber (manufactured by Central Glass Co., Ltd., Cefral Soft G180) 71.0 wt
%, Polyether ester amide (PAS40T manufactured by Toray Industries, Inc.) 6.0 wt% as an antistatic substance, and sodium dodecylbenzenesulfonate as an organic electrolyte 0.
A 25 wt% mixture was supplied to an extruder and a film was formed by an inflation extrusion molding method to obtain semiconductive tubes having an inner diameter of 18.6 mm and various thicknesses.

Production Example 3 A mixture of 100 parts by weight of vinyl chloride-grafted ethylene / vinyl acetate copolymer (Smedica N5142E, manufactured by Sekisui Chemical Co., Ltd.) and 15.9 parts by weight of carbon black as a conductive material was extruded. And the film has a volume resistivity of 5.1 × 10 ² Ω.
A cm conductive film was obtained.

Examples 1 to 3 and Comparative Examples 1 and 2 A cylindrical metal mold having an outer diameter of 18.55 mm was coated with the conductive film obtained in Production Example 3 and further obtained in Production Example 2. The obtained semiconductive tube is covered and heated in a hot air dryer at 210 ° C. for 20 minutes to obtain a laminated tube having a conductive resin layer (B) as an inner layer and a semiconductive resin layer (C) as an outer layer. It was Then, the laminated tube was fitted onto the conductive rollers of various hardnesses obtained in Production Example 1 and heated in a hot air dryer at 120 ° C. for 10 minutes to form the conductive resin layer (B) of the laminated tube. The conductive elastic layer (A) of the roller was adhered to obtain a semiconductive roller.

[0027]

[Table 1] (1) Hardness is represented by JIS-A hardness. (2) The state of the transferred image is good (◯), there is some defective portion (Δ), and bad (×).

Semi-conductive resin layer (C) as in Comparative Example 1
When the thickness of the semi-conductive resin layer (A) exceeds 100 μ as in Comparative Example 2, on the contrary, when the thickness is less than 50 μ, the electric charge leaks. The surface hardness was so high that good transfer could not be performed. In the case of Example 3 in which the hardness of the conductive elastic layer (A) exceeds 35, the surface hardness of the obtained roller is high and the transfer state is a little bad even though the hardness is the same as that of Example 1. It was

Comparative Example 3 The conductive roller of JIS-A hardness 30 obtained in Production Example 1 was covered with the semiconductive tube having a thickness of 60 μm obtained in Production Example 2 and placed in a hot air dryer at 120 ° C. A semiconductive transfer roller was manufactured by leaving it for 10 minutes, but the adhesiveness between the semiconductive resin layer (C) and the conductive elastic body layer (A) was poor, and the semiconductive resin layer ( C) slipped due to delamination and could not be used as a transfer roller.

Comparative Example 4 A semiconductive transfer roller was manufactured in the same manner as in Comparative Example 3 except that the temperature of the hot air dryer was 220 ° C., but the conductive elastic layer (A) was deformed by heat during heating. As a result, the shape became distorted and it could not be used as a transfer roller.

Examples 4 to 7 and Comparative Example 5 A semiconductive tube having a composition shown in Table 2 and having a thickness of 60 μm was obtained in the same manner as in Production Example 2. After the obtained tube and the conductive film obtained in Production Example 3 were laminated in the same manner as in Examples 1 and 2, the JIS-obtained in Production Example 1 was used.
A transfer roller was obtained by covering the conductive roller with A hardness of 30 and heating in a hot air dryer at 120 ° C. for 10 minutes. The performance of the obtained transfer roller is shown in Table 2.

[0032]

[Table 2] (1) Hardness is represented by JIS-A hardness. (2) The state of the transferred image is shown as good (◯), slightly defective (Δ), and bad (×).

As is clear from Table 2, when polyetheramide is used as the antistatic substance, the change in volume resistivity with the change in the amount used is extremely small, and the semiconductivity can be easily controlled. .. Further, in the case of Comparative Example 5 in which no fluorine rubber was used, the hardness of the obtained transfer roller was too high, and good transfer could not be performed.

[0034]

The transfer roller of the present invention uses a polyvinylidene fluoride resin having a high dielectric constant and fluororubber as the main components in the semiconductive resin layer (C) on the surface thereof, and therefore has a large capacitance. Not only the transfer efficiency is good, but also the releasability is good, so that even if scattered toner adheres, it can be easily removed.
Moreover, since fluorine rubber is used as a component, the surface hardness of the entire transfer roller is low and the transfer can be performed with an appropriate transfer pressure. When polyetheramide or polyetheresteramide is used as the antistatic substance, the semiconductive resin layer (C) obtained is uniform because the antistatic substance has good compatibility and dispersibility. It exhibits volume resistivity and can prevent troubles such as leak current. Further, since the conductive resin layer (B) having a melting point of 100 ° C. or lower is produced by heating and fusing, the conductive elastic body layer (A) and the semiconductive resin layer (C) are the conductive resin layers. It adheres through (B). Therefore, the electric conduction between layers is smooth, and there is no problem such as slipping due to delamination during rotation. Since the semiconductive transfer roller of the present invention has such good properties, it is possible to further reduce the weight, size and speed of electrostatic recording devices such as electrophotographic copying machines, laser printers and facsimiles. Is possible. Further, according to the present invention, the semiconductive transfer roller can be manufactured.

Claims (5)

[Claims] 1. A transfer roller for transferring a toner image adhered to an electrostatic latent image on a photoconductor to a recording sheet by electrostatic force, wherein the transfer roller has a volume resistivity of 10 ⁷ Ωcm on the outer circumference of a rotating shaft. The following conductive elastic material layer (A), volume specific resistance is 10 ⁵ Ωcm or less, melting point is 100 ° C. or less conductive resin layer (B), and volume specific resistance is 10 ⁸ to 10
^A semiconductive resin layer (C) in the range of ¹² Ωcm is laminated in this order, and the semiconductive resin layer (C) is 50 μm or more, 10
Polyvinylidene fluoride resin having a thickness of 0 μm or less
A semi-conductive transfer roller comprising a mixture of 67 wt%, fluororubber 30 to 82 wt% and antistatic substance 3 to 15 wt%. 2. The semiconductive transfer roller according to claim 1, wherein the antistatic substance is a polyether ester amide or a polyether amide. 3. The semiconductive transfer roller according to claim 1, wherein the conductive resin layer (B) is composed of a vinyl chloride graft ethylene / vinyl acetate copolymer. 4. The JIS-A of the conductive elastic layer (A).
The surface hardness is 25 to 35.
The semiconductive transfer roller described. 5. A rotating shaft having a volume resistivity of 10 ⁷ Ωcm or less and a conductive elastic layer (A) coated on the inner layer has a volume resistivity of 10 ⁵ Ωcm or less and a melting point of 100 ° C. or less. Resin layer (B) having a volume resistivity of 10 ⁸ to
A semi-conductive resin layer (C) in the range of 10 ¹² Ωcm is an outer layer, and a cylindrical tube is externally fitted and heated to a temperature of 150 ° C. or lower to melt the conductive resin layer (B). The method for producing a semiconductive transfer roller according to claim 1, wherein the conductive elastic layer (A), the conductive resin layer (B) and the semiconductive resin layer (C) are bonded together.