JPH09211933A - Semiconductor roller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductive roller which is decreased in the variations of resistance values and is low in rubber hardness as a semiconductive roller which is used for electrophotographic machines and is used by bringing this roller into contact with a photoreceptor directly or via paper. SOLUTION: The outer peripheral surface of the conductive elastic layer 3 of the semiconductive roller 1 constituted by providing the surface of a metallic shaft 2 with the conductive elastic layer 3 is provided with a resistance control layer 4 consisting of a curable compsn. contg. (A) a polymer which has at least one piece of alkenyl groups in the molecule and of which the repeating unit constituting the main chin is an oxyalkylene unit, (B) a hardener which has >=2 pieces of hydrosillyl groups in the molecule and (C) a hydrosillylating catalyst.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to various rollers and paper feeding for use in contact with a photoconductor, which are included in an electrophotographic machine such as an electronic copying machine or a printer for copying or printing by utilizing electrostatic force. The present invention relates to a semi-conductive roller used as a roller for automobiles.

[0002]

2. Description of the Related Art In an electrophotographic machine, toner is electrostatically attracted and attracted to a photosensitive member on which an electrostatic latent image corresponding to an original image is formed, and the toner is transferred to a fed sheet,
Then, the toner image carried on the paper is fused by heat so that the original image is fixed on the paper. Specifically, first, the surface of the photoconductor is charged (charging) by a charging member such as a charging roller, and then the surface of the photoconductor is imagewise exposed to form an electrostatic latent image (exposure). The electrostatic latent image is used to attract and adsorb toner from the developing roller using electrostatic force (development), and the fed sheet is charged from the back side by the transfer roller to transfer the toner on the surface of the photoconductor onto the sheet. Then, the toner transferred onto this paper is fused by heat to be fixed (fixed) on the paper. After that, the surface of the photosensitive member is charged again by the charging member, and copying is repeated by the same process as described above. In the above case, since a small amount of toner remains on the surface of the photoconductor during the transfer from the photoconductor to the paper, the surface of the photoconductor after the transfer is cleaned (cleaning). In addition, since there is residual charge on the surface of the photoconductor after cleaning, in order to prevent uneven density during the next image formation, the residual charge is uniformly applied to the photoconductor surface by a pre-exposure lamp. Remove (static elimination).

That is, in the electrophotographic machine, the photoconductor is subjected to the processes of charging, exposure, development, transfer, cleaning and charge removal, and the toner transferred onto the paper (transfer paper) undergoes the fixing process. After that, the document image is fixed on the transfer paper. In order to perform each of the above processes, each position around the photoconductor is brought into contact with the photoconductor such as a charging roller or a developing roller, or is brought into contact with the photoconductor via a paper like a transfer roller. Various rollers to be used are provided.

The various rollers around the photosensitive member are generally semiconductive, that is, the resistance value of the roller is 10 ³ to 1 1.
It is required to be about 0 ⁸ Ω. Roller resistance is 1
If it is smaller than 0 ³ Ω, there is a risk of dielectric breakdown of the roller when a defect such as a pinhole occurs in the photoconductor.
If the roller resistance value is larger than 10 ⁸ Ω, for example, in the case of a charging roller, the photosensitive member is not uniformly charged, and defects such as white spots appear on the image. Further, in the case of a developing roller, there often occurs a problem that a sufficient image density cannot be obtained.

The roller is generally made of an elastic base material such as urethane rubber, chloroprene rubber, EP rubber or silicone rubber, and conductive particles such as conductive particles such as carbon black or metal powder or conductive fibers such as carbon fiber. A mixture of substances that impart the properties is often used.

The roller is required to have uniform conductivity over the entire roller. However, when the conductivity is controlled by controlling the distance between the particles such as carbon black, the conductive particles are dispersed. Note that the roller resistance value varies greatly depending on the condition.

For this reason, the roller is constituted by a plurality of layers, the elastic layer is made of a low resistance to reduce the variation of the resistance value, and the surface of the elastic layer having a low resistance is comparatively tens to hundreds of μm. By forming a coating layer having a large resistance value, a semi-conductive roller is obtained as a whole.

[0008]

Conventionally, epichlorohydrin-based rubbers such as epichlorohydrin and epichlorohydrin-ethylene oxide copolymer rubber have been used as the coating layer. However, these rubber materials have large rubber hardness, and when used as a coating layer, the hardness of the entire roller increases, so that a uniform nip width cannot be obtained between the rubber material and the photosensitive member. When used as a charging roller, there arises a problem that the photoconductor cannot be uniformly charged.

If a plasticizer is added to reduce the rubber hardness of the coating layer, the plasticizer may migrate to the surface of the photoconductor and contaminate the photoconductor.

Further, since it is generally necessary to vulcanize the epichlorohydrin type rubber material with a vulcanization accelerator such as a metal oxide, it takes a long time to form a coating layer and the man-hours increase from the viewpoint of productivity. There was a problem.

In view of the above points, the present invention is used in electrophotographic machines such as electronic copying machines and printers, as various semi-conductive rollers provided around the photoconductor, and having a uniform nip width when contacting the photoconductor. The present invention provides a semi-conductive roller which has an appropriate hardness that does not contaminate the photoconductor by contact, and has good productivity.

[0012]

The present invention has been made to solve the above problems, and is a semiconductive roller used in an electrophotographic machine, in which a conductive elastic layer is provided on a metal shaft. In the semiconductive roller provided, a polymer having (A) at least one alkenyl group in the molecule on the outer peripheral surface of the conductive elastic layer, and 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 resistance adjusting layer comprising a curable composition containing a hydrosilylation catalyst is provided. A semiconductive roller (claim 1), wherein the resistance adjusting layer has a thickness of 5 to 300 μm. A semi-conductive roller (claim 2), and in the semi-conductive roller, in addition to (A), (B), and (C) as the conductive elastic layer,
A semiconductive roller (claim 3) using a curable composition comprising (D) a conductivity-imparting agent, and
A semiconductive roller having a resistance adjusting layer provided on the outer peripheral surface of a conductive elastic layer and a protective layer further provided on the surface of the semiconductive roller (claim 4).

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The semiconductive roller of the present invention is
For example, as shown in FIG. 1, a SU having a diameter of about 1 to 12 mm
Metal shuffs such as S (stainless steel) and aluminum
Around the toe 2 with JIS A hardness of about 5 to 40 °,
Preferably, the thickness is about 10 to 30 ° and the thickness is about 1 to 15 mm.
After the conductive elastic layer 3 is provided, the outer surface of the conductive elastic layer 3 is electrically charged by the roller 1.
A resistance adjusting layer 4 is provided to adjust the air characteristics, and
The surface of the resistance adjusting layer 4 is covered with a protective layer 5.
You. The surface hardness of this roller is JIS A hardness.
And is preferably 30 ° or less. Also this semi-conductive
The conductivity of the elastic roller 1 depends on the application of the roller 1.
Although different, for example, when using it as a charging roller
Has a roller resistance of 10^Four-10⁸Ω,
And 10^Five-10 ⁷Ω is preferable, and development
10 when used as a roller^Three-10⁸Ω,
And 10^Four-10⁷Ω is preferable, and generally
10^Three-10⁸About Ω, and even 10^Four-10⁷Ω
belongs to.

The resistance adjusting layer 4 in the semi-conductive roller 1 smoothes the resistance variation of the conductive elastic layer 3,
Since the roller 1 has a function of making the resistance value of the entire roller 1 uniform and a function of adjusting the resistance of the roller 1 as a whole, the volume resistivity is larger than that of the conductive elastic layer 3, and the variation in the volume resistivity is small. Required.

In the present invention, the resistance adjusting layer 4 is a polymer having at least one alkenyl group in the molecule and the repeating unit constituting the main chain is an oxyalkylene unit, (component (A)), A layer comprising a curable composition (I) containing a curing agent (component (B)) having two or more hydrosilyl groups in the molecule and a hydrosilylation catalyst (component (C)) is provided.

The component (A) in the curable composition (I) which constitutes the resistance adjusting layer 4 is a component which reacts with the component (B), which is a curing agent, and cures to become a cured product having rubber elasticity. is there.

The repeating unit constituting the main chain of the component (A) is an oxyalkylene unit, and the main chain has a compound having two or more active hydrogens as a starting material, such as ethylene glycol, propylene glycol, a bisphenol compound and glycerin. , Trimethylolpropane, pentaerythritol, etc., to polymerize a C ₂ -C ₄ alkylene oxide. Specific examples of the polymer constituting the main chain thus produced include, for example, polyethylene oxide, polypropylene oxide, polybutylene oxide, and further two or more kinds selected from ethylene oxide, propylene oxide and butylene oxide. Examples thereof include random or block copolymers, and it is preferable that an alkenyl group is introduced at the terminal from the viewpoint of rubber elasticity.

Specific examples of the polymer (component (A)) having at least one alkenyl group in the molecule and having a repeating unit constituting the main chain as an oxyalkylene unit include a cured product having a low hardness. From the viewpoint of, the repeating unit of the main chain is preferably an oxypropylene unit, and in the case where water absorption is required, a copolymer in which a part of the oxypropylene unit is changed to an oxyethylene unit is preferable. .

The number of alkenyl groups contained in the component (A) is required to be at least one from the viewpoint of reacting with the component (B), but is preferably 2 to 6.

The molecular weight of the component (A) is a number average molecular weight (Mn) from the viewpoint of the balance between reactivity and low hardness.
500-50,000, and 1,000-20,
000 is preferable, and those having an alkenyl group at the molecular terminal are preferable in terms of low hardness and the like.

Next, the curing agent having at least two hydrosilyl groups in the molecule which is the component (B) in the curable composition (I) is at least one in the molecule which is the above-mentioned component (A). Is a component that acts as a curing agent for a polymer in which the repeating unit having an alkenyl group and constituting the main chain is an oxyalkylene unit.

Since the component (B) has at least two hydrosilyl groups in the molecule, each hydrosilyl group reacts with the alkenyl group present in the molecule of the component (A) to cure. The number of said hydrosilyl groups is preferably 2
-50, more preferably 2-30, and even 2-2
0 is preferable, and 3 to 12 is particularly preferable. When the number of hydrosilyl groups is less than two, the curing rate when the curable composition (I) is cured by a hydrosilylation reaction becomes slow, and curing failure often occurs. When the number of hydrosilyl groups is more than 50, the stability of the curing agent as the component (B), and thus the stability of the curable composition (I), deteriorates, and a large amount of hydrosilyl groups remains after curing. It is likely to remain in the cured product, causing voids and cracks.

Having one hydrosilyl group means S
It means having 1 iH, that is, 1 H that bonds to Si, and in the case of SiH ₂ , it has 2 hydrosilyl groups. However, H bonded to Si is more likely to bond to different Si. It is preferable in terms of good curability and rubber elasticity.

The number average molecular weight (Mn) of the component (B) is preferably 30,000 or less, more preferably 20,000 or less, and particularly preferably 15,000 or less from the viewpoint of roller processability. preferable. Considering the reactivity and compatibility with the component (A), 300 to 15,000 is more preferable.

The structure of the component (B) as described above is not particularly limited. For example, the general formula (1): R ¹ X _a (1) (wherein, X is a group containing at least one hydrosilyl group). , R ¹ is a monovalent to tetravalent hydrocarbon group having 2 to 150 carbon atoms,
a is an integer selected from 1 to 4, provided that when X contains only one hydrosilyl group, a is 2 or more) and has a number average molecular weight of 30,000 or less. A specific example is a hydrocarbon-based curing agent contained therein.

In the general formula (1), X represents a group containing at least one hydrosilyl group, and specific examples thereof include --SiH _n (CH ₃ ) _3-n (n = 1 to 1).
_{3), - SiH n (C} 2 H 5) 3-n (n = 1~3), -
_{SiH n (C 6 H 5)} 3-n (n = 1~3), - SiH 2
A hydrosilyl group containing only one silicon atom, such as (C ₆ H ₁₃ ),

[0027]

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A hydrosilyl group containing two or more silicon atoms, such as

[0029]

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[0030]

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[0031]

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Examples thereof include hydrosilyl groups derived from various chain-like, branched-like, and cyclic polyvalent hydrogen siloxanes. In the formula, m units and p units, n units and q units, m units and p units and x units, n units and q units, It is described that y units, m units and n units, and further, m units, n units, p units, and q units are connected by block bonding. However, these may be block bonds or random bonds. The same applies to the following description.

Of the above various hydrosilyl groups,
Since the hydrosilyl group-containing hydrocarbon curing agent as the component (B) is less likely to impair the compatibility with other organic polymers, the molecular weight of the part constituting the hydrosilyl group is 5
It is preferably at most 00, and in consideration of the reactivity of the hydrosilyl group, the following is preferred.

[0034]

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Hereinafter, these groups will be referred to as "groups represented by (Chemical Formula 5)".

Further, in the above general formula (1), R ¹ represents a monovalent to tetravalent hydrocarbon group having 2 to 150 carbon atoms and may be a group composed of a polymer. As a specific example,

[0037]

[Chemical 6]

[0038]

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(Note that these are disclosed in JP-A-3-9526.
No. 6, etc.), and specific examples of the group in which R ¹ is a polymer include ethylene, propylene,
A polymer obtained by polymerizing an olefinic compound having 2 to 6 carbon atoms such as 1-butene, isobutylene or the like as a main monomer, having 1 to 4 bonds, or a diene-based compound such as butadiene or isoprene alone. Polymerizing,
Examples thereof include those obtained by copolymerizing the olefin compound and the diene compound and then hydrogenating the compound and having 1 to 4 bonds.

Among the hydrocarbon type curing agents represented by the general formula (1) having R ¹ and X as described above, R ¹ is a hydrocarbon group having 5 to 20 carbon atoms and X is the above-mentioned (formula 5). The combination in the case of the groups shown is preferable from the viewpoint of increasing the reactivity and forming a good network structure, and the compatibility with the component (A). Among these, it is preferable that R ¹ is a hydrocarbon group having 5 to 12 carbon atoms in that the raw material can be easily obtained, and X is a cyclic polysiloxane compound among the groups represented by the above formula (5). This is preferred because compatibility with the component (A) is further improved. The compound obtained by this combination is preferable as the hydrocarbon-based curing agent. For example, for example,

[0041]

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And the like.

The method for producing the hydrosilyl group-containing hydrocarbon curing agent which is the component (B) as described above is not particularly limited, and it may be produced by any method.

For example, (1) a SiCl group may be included in the molecule.
Hydrocarbon curing agent, LiAlH _Four, NaBH_FourSuch
To reduce the SiCl groups in the curing agent to SiH groups
(2) a functional group X in the molecule¹Have
The hydrocarbon compound and the functional group X in the molecule¹React with
Functional group Y¹Having both amino and hydrosilyl groups
(3) Charcoal containing alkenyl group
At least two hydrosilyl groups per hydride compound
Hydrosilylation of Polyhydrosilane Compounds Having Groups
After the reaction, the hydrosilyl group is
Method of leaving in the molecule of the system compound, and the like.
You.

Of the above methods, the method (3) can be preferably used because the manufacturing process is generally simple. In this case, two or more of the hydrosilyl groups of some of the polyhydrosilane compounds may react with the alkenyl group of the hydrocarbon-based compound to increase the molecular weight. Even if it is used as a component (B), there is no problem.

Further, a polysiloxane-based curing agent can be used as the component (B). Specific examples thereof include chain-like and cyclic polyorganohydrogen siloxanes (including polyoxyalkylene modified products, styrene modified products, olefin modified products, etc.) as described below.

[0047]

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(M and n are integers, 10≤m + n≤50, 2
≦ m, 0 ≦ n, R is a methyl group, and the molecular weight is 100 to 10,
000 polyoxyalkylene group or 2-20 carbon atoms
And may contain one or more phenyl groups. When a plurality of Rs are included, they need not be the same. )

[0049]

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(M and n are integers, 10≤m + n≤50, 2
≦ m, 0 ≦ n, R is a methyl group, and the molecular weight is 100 to 10,
000 polyoxyalkylene group or 2-20 carbon atoms
And may contain one or more phenyl groups. When a plurality of Rs are included, they need not be the same. )

[0051]

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(M and n are integers, 3≤m + n≤20, 2≤
m ≦ 19, 0 ≦ n ≦ 18, R is methyl group, molecular weight is 10
The polyoxyalkylene group may have 0 to 10,000 or a hydrocarbon group having 2 to 20 carbon atoms and may contain one or more phenyl groups. When a plurality of Rs are included, they need not be the same. ) In order to improve the compatibility with the component (A),
It is preferred that R contains a phenyl group. Furthermore, because of easy availability, —CH ₂ —CH ₂ —C
₆ H _5, is _{-CH 2 -CH (CH 3) -C} 6 H 5, also from the viewpoint of storage _{stability, -CH 2 -CH (CH 3)} -
C ₆ H ₅ are preferred.

The curable composition (I) constituting the resistance adjusting layer 4 contains the above-mentioned components (A) and (B) together with
The hydrosilylation catalyst as the component (C) is used.

The hydrosilylation catalyst which is the component (C) is not particularly limited, and specific examples thereof include solid platinum supported on a carrier such as platinum, alumina, silica, carbon black, chloroplatinic acid, Examples include complexes of chloroplatinic acid with alcohols, aldehydes, ketones, platinum / olefin complexes, platinum / phosphite complexes, and the like.

The curable composition (I) comprises the above (A) to
It is adjusted from the component (C). The proportion of the component (A) and the component (B) used is such that the hydrosilyl group in the component (B) is 0.2 to 5.0 moles, and more preferably 0.4 to 1 mole, per 1 mole of the alkenyl group in the component (A). It is preferable to use 2.5 mol from the viewpoint of rubber elasticity. The amount of the hydrosilylation catalyst as the component (C) used is within the range of 10 ^-1 to 10 ^-6 mol with respect to 1 mol of the alkenyl group in the component (A).

The resistance adjusting layer 4 made of the curable composition (I) as described above may have a volume resistivity higher than that of the conductive elastic layer 3, and has a volume resistivity of about 10 ⁸ to 10 ¹² Ω · cm. And In order to obtain a predetermined roller resistance value, a conductivity imparting agent which is the component (D) may be added to the curable composition (I). Specific examples of the conductivity-imparting agent as the component (D) include carbon black, fine metal powder, and
Organic compounds or polymers containing primary ammonium base, carboxylic acid group, sulfonic acid group, sulfuric acid ester group, phosphoric acid ester group, etc., ether ester amide or ether amide imide polymer, ethylene oxide-epihalohydrin copolymer, methoxy polyethylene An organic antistatic agent such as a compound having a conductive unit represented by a glycol acrylate polymer or a polymer compound can be used, and a plurality of them may be used.

The resistance adjusting layer 4 usually has a thickness of 5
It is a layer of about 300 μm, preferably about 20 to 200 μm. When the thickness of the resistance adjusting layer 4 is less than 5 μm, the function of smoothing the resistance value variation of the conductive elastic layer 3 is often insufficient, and the withstand voltage of the roller tends to decrease. If it exceeds 300 μm, the roller resistance value tends to be too high.

The method of forming the resistance adjusting layer 4 is not particularly limited, and it may be formed on the outer peripheral surface of the conductive elastic layer 3 by a roll coater, dipping, spraying, brush coating or the like.

Next, specific examples of the conductive elastic layer 3 in the semiconductive roller 1 include urethane rubber, chloroprene rubber, EPDM, NBR, etc., and the above (A), (B), (C). By using the curable composition (II) containing the component (D) in addition to the component (2), a conductive elastic layer having characteristics such as low hardness and low compression set can be obtained.

With the component (D) in the conductive elastic layer 3,
The amount of the certain conductivity-imparting agent used is the above-mentioned components (A) to (C).
0.1 for every 100 parts (including parts by weight)
To 50 parts, and further 0.3 to 30 parts, the conductive elastic layer 3
Has a volume resistivity of 10^Three-10 ⁸Ω · cm, preferably
Is 10^Four-10⁷Used to be Ω · cm.

If necessary, silica, non-conductive fillers such as magnesium carbonate, and antioxidants may be added to the curable composition (II). The amount to be added is usually about 50 parts or less, preferably about 20 parts or less, based on 100 parts of the total amount of the components (A) to (D), from the viewpoint of not impairing good rubber elasticity.

Further, the protective layer 5 provided on the surface of the resistance adjusting layer 4 needs to have excellent abrasion resistance when it comes into contact with the photoconductor, and is made of a substance which does not contaminate the photoconductor. is necessary.

Specific examples of this protective layer include nylon,
An acrylic resin, a fluororesin, or the like can be used, and like the resistance adjusting layer 4, it is formed by a roll coater, dipping, spraying, brush coating, or the like.

The roller thus formed is brought into contact with the photosensitive member of an electrophotographic machine such as an electronic copying machine or a printer such as a charging roller, a developing roller and a transfer roller,
Alternatively, it is used as various rollers that are brought into contact with each other via paper or a roller for feeding paper.

[0065]

EXAMPLES Next, the semiconductive roller of the present invention will be explained based on examples.

Example 1 Number average molecular weight (Mn) 8,000, molecular weight distribution (Mw /
Mn) 2.0 (measured by GPC), viscosity 130P (20
100 ° C.) polyoxypropylene polymer (polyoxypropylene in which 90% of OH at both ends is allyl etherified), formula:

[0067]

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A polysiloxane curing agent (Si
A composition (a) was prepared by blending 6.9 g of H value of 0.358 mol / 100 g) and 0.06 g of 10% isopropyl alcohol solution of chloroplatinic acid (H ₂ PtCl ₆ ).

This composition (a) was further mixed with 0.5 g of Ketjen Black EC, and then 10 mmHg
The mixture was degassed with stirring for 120 minutes under reduced pressure conditions to obtain a composition (b).

The composition (b) thus obtained was coated around a stainless steel shaft having a diameter of 6 mm and cured in a mold at 120 ° C. for 30 minutes to give a conductive elastic layer having a thickness of 3 mm around the stainless steel shaft. Layers were provided.

Next, the composition (a) prepared in the same manner as above was degassed by stirring under a reduced pressure of 10 mmHg for 120 minutes, and then applied on the conductive elastic layer by using a roll coater, and 120 ° C. Then, the roller (c) having the resistance adjusting layer formed thereon was prepared by curing for 30 minutes inside the oven.

When the thickness of the resistance adjusting layer was measured by an outer shape measuring machine (manufactured by Keyence Corporation), it was 30 μm.

The obtained roller (c) was placed on a copper plate, a load of 500 g was applied to both ends of a stainless steel shaft, and the roller resistance value when DC 100 V was applied was measured four times at different measurement points. The roller resistance value was 4 × 10 ⁵ Ω on average. Moreover, when the ratio of the maximum value and the minimum value of the resistance value was taken as the variation of the roller resistance value,
It became 1.3 times.

The roller (c) thus obtained had a resistance value in the semiconductive region, and the variation in roller resistance value was small.

Next, alcohol-soluble nylon (CM; Toray Industries, Inc.) was applied as a protective layer on the surface of the roller (c) by spraying to a thickness of 50 μm, and then used for copying machine FC310 manufactured by Canon Inc. When the cartridge was incorporated as a charging roller and image formation was performed, a good image was obtained. The JISA hardness of this roller (c) was 27 °.

Examples 2 to 5 The thickness of the resistance adjusting layer is 10 μm, 50 μm, 100 μm,
Rollers (d) to (g) were produced in the same manner as in Example 1 except that the thickness was 200 μm, and the roller resistance value was measured in the same manner as described above. The results are shown in Table 1.

[0077]

[Table 1]

Each of the obtained rollers had a resistance value in the semiconductive region, and the variation in the roller resistance value was small.

Next, after forming a protective layer on the surfaces of the rollers (d) to (g) in the same manner as in Example 1, it was incorporated into a cartridge for a copying machine FC310 manufactured by Canon Inc. as a charging roller, and an image was formed. As a result of performing the bleaching, good images were obtained in all cases.

Example 6 The polysiloxane of Example 1 is of the formula:

[0081]

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The polysiloxane curing agent (Si
A roller (h) was produced in the same manner as in Example 1 except that the H value was 0.97 mol / 100 g) was changed to 2.7 g, and the roller resistance value was measured 4 times by changing the measurement points. The average value was 5 × 10 ⁵ Ω. In addition, the variation of the roller resistance value is 1.2 times, and the obtained roller (h) is
The resistance value was in the semiconductive region, and the variation in roller resistance value was small.

Comparative Example 1 The same as Example 1 was prepared until the conductive elastic layer was provided. Next, a methyl ethyl ketone solution of a copolymer of epichlorohydrin and ethylene oxide (Epichromer C: Daiso Co., Ltd.) was applied onto the conductive elastic layer by spraying, and the solution was heated in an oven at 150 ° C. to 60 ° C.
It was vulcanized for a minute to prepare a roller having a resistance adjusting layer.

When the thickness of the resistance adjusting layer was measured with an outer shape measuring machine (manufactured by Keyence Corp.), it was 60 μm.

The resistance value of the obtained roller was measured 4 times at different measurement points, and the average value was 2 × 10 ⁶ Ω.
The variation in roller resistance value was 1.5 times.

Next, alcohol-soluble nylon (CM: Toray Industries, Inc.) was spray-coated on this roller as a protective layer to a film thickness of 50 μm, and then a cartridge for copying machine FC310 manufactured by Canon Inc. was charged. As a result of incorporating it as a roller and forming an image, white spots due to poor charging were observed on the image, and a good image could not be obtained. The JIS A hardness of this roller is 40 °.
Met.

[0087]

As described above, according to the present invention, various rollers, which are used by being brought into contact with a photoconductor or through paper, which are included in an electronic copying machine, rollers for feeding paper, and the like are used. As the semiconductive roller to be used, it is possible to obtain a roller having a small variation in roller resistance value and a small rubber hardness.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a semi-conductive roller according to the present invention. 1 roller, 2 metal shaft, 3 conductive elastic layer, 4 resistance adjusting layer, 5 protective layer.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Ogoshi 2-1-1 Hiei Tsuji, Otsu City, Shiga Prefecture Kanebuchi Chemical Industry Co., Ltd. (72) Kazuyoshi Mimura 2-1-1 Hiei Tsuji, Otsu City Shiga Prefecture Kanebuchi Chemical Industry Co., Ltd.

Claims (4)

[Claims] 1. A semi-conductive roller used in an electrophotographic machine, comprising a metal shaft and a conductive elastic layer provided on the shaft, wherein (A) is provided on the outer peripheral surface of the conductive elastic layer. ) A polymer having at least one alkenyl group in the molecule and a repeating unit constituting the main chain being an oxyalkylene unit, (B) a curing agent having two or more hydrosilyl groups in the molecule, and ( A semiconductive roller provided with a resistance adjusting layer made of a curable composition containing C) a hydrosilylation catalyst. 2. The thickness of the resistance adjusting layer is 5 to 300 μm.
The semiconductive roller according to claim 1, wherein 3. The (A), as the conductive elastic layer,
The semiconductive roller according to claim 1, wherein a curable composition comprising (D) a conductivity-imparting agent in addition to (B) and (C) is used. 4. A semiconductive roller having a protective layer further provided on the surface of the semiconductive roller having the resistance adjusting layer according to claim 1.