WO2009096096A1 - Electroconductive molded product and process for producing the electroconductive molded product - Google Patents

Abstract

Disclosed is an electroconductive molded product that can reduce surface tackiness while maintaining low hardness, can simultaneously have good moldability and recycle properties, and, even with the addition of a small amount of a salt, can realize a satisfactorily low level of electric resistance. The electroconductive molded product is a sheet- or roll-shaped molded product formed of a dynamically crosslinked thermoplastic elastomer composition produced by mixing an ethylene oxide-propylene oxide-allyl glycidyl ether copolymer and a salt having an anion containing a fluoro group and a sulfonyl group to an elastomer composition comprisingrubber component, produced by mixing an ethylene-propylene-diene copolymer rubber (EPDM) and an acrylonitrile-butadiene rubber (NBR) at a mixing ratio of EPDM : NBR = 100 : 0 to 5 : 95, which has been dynamically crosslinked and dispersed in any one of or a mixture of both a thermoplastic resin and a thermoplastic elastomer to render the elastomer composition electrically conductive. The electroconductive molded product is characterized in that the surface of the electroconductive molded product has been irradiated with ultraviolet light.

Description

Conductive molded article and method for producing the same

The present invention relates to a conductive molded article, and more specifically, a conductive molded article suitably used in an OA apparatus such as an ink jet printer, a laser printer, an electrostatic copying machine or a facsimile machine, and an image forming apparatus such as an automatic deposit dispenser (ATM). About.

The conductive member in the image forming apparatus needs to have a suitable stable electrical resistance value.
Conventionally, as a method of imparting conductivity to this kind of conductive member, a method of using an electronic conductive polymer composition in which a conductive filler such as metal oxide powder or carbon black is blended in a polymer, and urethane There is a method using an ion conductive polymer composition such as rubber, acrylonitrile butadiene rubber, epichlorohydrin rubber and the like.

When an electronically conductive polymer composition is used for the conductive member, control of the electrical resistance becomes very difficult because there is a region where the electrical resistance changes rapidly due to a slight change in the amount of the conductive filler added. There's a problem. In addition, the conductive filler is difficult to uniformly disperse in the polymer, and there is also a problem that the electrical resistance value varies in the conductive member.
In addition, the electric resistance value of the conductive member using the electron conductive polymer composition has a problem depending on the applied voltage. This tendency is particularly noticeable when carbon black is used as the conductive filler. Furthermore, if too much a conductive filler such as carbon black is compounded, it becomes difficult to carry out molding processing.

Since the conductive member using the electronically conductive polymer composition has the above problems, the recent progress in image quality improvement technology such as digitization and colorization is not remarkable for the electronically conductive polymer composition. Ion conductive polymer compositions tend to be particularly preferred.

Most of the ion conductive polymer compositions that have been put to practical use for conductive members are vulcanized rubber compositions, but the vulcanized rubber compositions have the disadvantage that they are not thermoplastic and can not be recycled.
Moreover, when using the conventional ion conductive agent, there existed a problem that an electrical resistance could not be reduced efficiently. Therefore, when a large amount of ion conductive agent is added, problems such as bleeding may occur and mechanical properties such as compression set and hardness may be deteriorated.

Therefore, the present applicants have developed a conductive polymer composition that has both durability such as rubber, elasticity, flexibility and moldability such as resin and is excellent in recyclability and has low electrical resistance.
Specifically, in Japanese Patent Application Laid-Open Nos. 2004-51829 (Patent Document 1) and 2004-269854 (Patent Document 2), a rubber or / and / or crosslinkable into a thermoplastic resin and / or a thermoplastic elastomer is provided. Dynamically conducted by blending a polymer having an ether or ester structure and a salt having an anion having a fluoro group and a sulfonyl group into an elastomer composition in which a thermoplastic elastomer is dynamically crosslinked and dispersed. Provided are a crosslinked thermoplastic elastomer composition and a conductive member using the composition.

The present inventors have conducted further studies to put into practical use the product produced using the above-mentioned dynamically cross-linked thermoplastic elastomer composition in accordance with the demand of the market becoming more advanced, and the hardness We found that there is room to improve the surface and surface properties.
Specifically, when the product is used in contact with another member as, for example, a transfer roller, a certain degree of nip is required, and a demand for low hardness can not be avoided. However, if a large amount of softener is blended for the purpose of lowering hardness, the softness may bleed to other members in contact due to the increase in surface adhesive force, and the friction resistance is high. Problems such as getting worse may occur. In addition, when the hardness is lowered, the adhesion on the surface becomes high, which may cause a defect due to the adhesion of the toner. Thus, there have been frequent cases where it is necessary to overcome the antinomy.

JP 2004-51829 A JP 2004-269854 A

The present invention can reduce the surface tackiness while maintaining low hardness and has good formability and recyclability, and can realize sufficiently low electrical resistance even with the addition of a small amount of salt, hence It is an object of the present invention to provide a conductive molded article capable of preventing migration contamination and deterioration in physical properties caused by a large amount of salt.

In order to solve the above-mentioned subject, the present invention is
The rubber component prepared by blending ethylene-propylene-diene copolymer rubber (EPDM) and acrylonitrile butadiene rubber (NBR) at EPDM: NBR = 100: 0 to 5:95 is either one of thermoplastic resin and thermoplastic elastomer or In the elastomer composition which is dynamically crosslinked and dispersed in both mixtures,
A conductive, dynamically crosslinked thermoplastic elastomer composition obtained by blending an ethylene oxide-propylene oxide-allyl glycidyl ether (EO-PO-AGE) copolymer and a salt having an anion having a fluoro group and a sulfonyl group. ,
The conductive molded article is characterized in that the surface of the sheet-like or roll-like molded article of the dynamically crosslinked thermoplastic elastomer composition is subjected to UV irradiation treatment.

As a result of intensive studies to solve the above problems, the present inventors conducted ultraviolet irradiation treatment on the surface of a molded article made of a dynamically cross-linked thermoplastic elastomer composition having a specific composition, thereby achieving low hardness and adhesion of the surface. It succeeded in making reduction compatible and came to this invention.

The EPDM used in the present invention includes non-oil spread type EPDM consisting only of a rubber component and oil spread type EPDM containing a parent oil as well as a rubber component, but any type can be used in the present invention . Examples of diene monomers in EPDM include dicyclopentadiene, methylene norbornene, ethylidene norbornene, 1,4-hexadiene or cyclooctadiene and the like.

As the NBR used in the present invention, a low nitrile NBR having an acrylonitrile content of 25% or less, a middle nitrile NBR having an acrylonitrile content of 25 to 31%, a middle and high nitrile NBR having an acrylonitrile content of 31 to 36%, and an acrylonitrile content of 36 You may use any high nitrile NBR which is% or more.
Above all, in order to reduce the specific gravity of rubber, it is preferable to use low-nitrile NBR having a small specific gravity. More specifically, it is suitable to use an NBR having an acrylonitrile content of 15 to 25%, preferably 15 to 20%.

The blend ratio of EPDM and NBR is such that EPDM: NBR = 100: 0-5: 95. If NBR / (EPDM + NBR)> 0.95, a dispersion failure of the NBR will occur when the rubber component is dispersed in the mixture of one or both of the thermoplastic resin and the thermoplastic elastomer.

The rubber component is dynamically crosslinked and dispersed in a mixture of one or both of a thermoplastic resin and a thermoplastic elastomer. Among them, it is preferable that the rubber component is dynamically crosslinked and dispersed in a thermoplastic resin or in a mixture of a thermoplastic resin and a thermoplastic elastomer.

A well-known thing can be used as said thermoplastic resin. For example, olefin resin, polystyrene (PS), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), nylon and the like can be mentioned. Among them, it is preferable to use an olefin resin. As the olefin resin, for example, polyethylene, polypropylene, ethylene ethyl acrylate resin, ethylene vinyl acetate resin, ethylene-methacrylic acid resin, ionomer resin, etc. may be mentioned, but it is preferable to use polypropylene or polyethylene, and it is more preferable to use polypropylene .

As the thermoplastic elastomer, known thermoplastic elastomers can be used. Specific examples thereof include styrene-based elastomers, chlorinated polyethylene, vinyl chloride-based elastomers, olefin-based elastomers, urethane-based elastomers, ester-based elastomers, and amide-based elastomers.

Among the thermoplastic elastomers, it is preferable to use a styrenic elastomer.
As a styrene-based elastomer, a block copolymer of a polymer block (A) mainly composed of a styrene-based monomer and a block (B) mainly composed of a conjugated diene compound and a conjugated diene polymerization unit of the block copolymer hydrogenated Can be illustrated. Examples of the styrene-based monomer include styrene, α-methylstyrene, vinyl toluene and t-butylstyrene. These monomers may be used alone or in combination of two or more. Among them, styrene is preferable as the styrene-based monomer. Further, as the conjugated diene compound, butadiene, isoprene, chloroprene, 2,3-dimethyl butadiene and the like can be exemplified. These may be used alone or in combination of two or more.

Specific examples of styrene elastomers include styrene-butadiene-styrene copolymer (SBS), styrene-isoprene-styrene copolymer (SIS), styrene-ethylene / butylene-styrene copolymer (SEBS), styrene- Examples thereof include ethylene / propylene-styrene copolymer (SEPS) and styrene-ethylene-ethylene / propylene-styrene copolymer (SEEPS). Among them, it is more preferable to use a hydrogenated styrene-based thermoplastic elastomer, and it is particularly preferable to use a styrene-ethylene-ethylene / propylene-styrene copolymer (SEEPS).

The thermoplastic resin and / or the mixture of either or both of the thermoplastic elastomer and the thermoplastic resin are preferably contained in a ratio of 2 to 150 parts by mass with respect to 100 parts by mass of the rubber component.
When the compounding amount is less than 2 parts by mass, the rubber component can not be dispersed in the resin matrix, and processing becomes difficult, and the strength and the abrasion resistance of the conductive molded article of the present invention decrease. On the other hand, when the compounding amount exceeds 150 parts by mass, the hardness becomes high, which may cause problems such as poor transfer and poor transport when used as a member for an image forming apparatus.

When using a mixture of a thermoplastic elastomer and a thermoplastic resin, it is desirable that the mixture of the thermoplastic elastomer and the thermoplastic resin be an elastomer even after mixing. The reason is that the hardness of the elastomer composition finally obtained by dispersing the rubber component is lower.
The mixing ratio of the thermoplastic elastomer and the thermoplastic resin in the mixture can be determined according to the type of the elastomer and resin used, but 1 mass of the thermoplastic resin is based on 100 parts by mass of the thermoplastic elastomer. It is preferable that it is part or more and 100 parts by mass or less. If the mixing amount of the thermoplastic resin is less than 1 part by mass, the effect of mixing the thermoplastic resin can not be observed, and if the mixing amount of the thermoplastic resin is more than 100 parts by mass, the mixture becomes an elastomer. . The mixing amount of the thermoplastic resin is more preferably 20 to 80 parts by mass with respect to 100 parts by mass of the thermoplastic elastomer.

A crosslinking agent is usually used to dynamically crosslink the rubber component. As the crosslinking agent, for example, a known crosslinking agent such as a resin crosslinking agent or a peroxide can be used. Among them, it is preferable to use a resin crosslinking agent.
A resin crosslinking agent is a synthetic resin that causes a crosslinking reaction to occur in the rubber component by heating etc., compared to the case where sulfur and a vulcanization accelerator are used in combination, it is difficult to produce a bloom and has a small compression set and a small deterioration in physical properties. It is preferable at the point which is excellent in maintenance and durability. Furthermore, since the crosslinking time is shorter than that of the sulfur crosslinking system, dynamic crosslinking can be progressed within a short time staying in the extruder.

An elastomer composition in which a rubber component containing at least EPDM and NBR in a specific ratio as described above is dynamically crosslinked and dispersed in a mixture of one or both of a thermoplastic resin and a thermoplastic elastomer. By blending a PO-AGE copolymer and a salt having an anion having a fluoro group and a sulfonyl group, a conductive, dynamically crosslinked thermoplastic elastomer composition is obtained.
By blending the EO-PO-AGE copolymer with the above-mentioned salt, the copolymer stabilizes the ions derived from the salt, and there is an advantage that a significant effect can be obtained for the reduction of the electric resistance value.

The ethylene oxide ratio in the EO-PO-AGE copolymer is preferably 55 mol% or more and 95 mol% or less, more preferably 65 mol% or more and 95 mol% or less. The cation derived from the salt is stabilized with an ethylene oxide unit or a propylene oxide unit, and in general, the ethylene oxide unit has higher stabilization ability than the propylene oxide unit. Therefore, the higher the ratio of ethylene oxide units, the more ions can be stabilized. On the other hand, when the ratio of ethylene oxide units exceeds 95 mol%, the ethylene oxide units are crystallized.
In the EO-PO-AGE copolymer, the copolymerization ratio of allyl glycidyl ether is preferably 1 mol% or more and 10 mol% or less. If it is less than 1 mol%, bleeding and contamination of other members are likely to occur, while if it exceeds 10 mol%, tensile strength, fatigue characteristics, flex resistance and the like are apt to deteriorate.
The number average molecular weight of the EO-PO-AGE copolymer is preferably 10,000 or more, and more preferably 30,000 or more. The reason for this is to prevent bleed bloom and photoreceptor contamination.

The EO-PO-AGE copolymer may be dynamically crosslinked. The EO-PO-AGE copolymer may be simultaneously crosslinked when dynamically crosslinking the rubber component in the elastomeric composition, or separately from the dynamic crosslinking of the rubber component in the elastomeric composition. The copolymer may be crosslinked. As a crosslinking agent to be used, for example, a known crosslinking agent such as a resin crosslinking agent or a peroxide can be mentioned, but it is preferable to use a peroxide.

As a salt provided with an anion having a fluoro group and a sulfonyl group, a salt provided with at least one anion selected from the following chemical formulas 1, 2 and 3 is preferable.

(Wherein, X ₁ and X ₂ may be the same or different, and represent a functional group having 1 to 8 carbon atoms including a carbon atom, a fluorine atom and a sulfonyl group (—SO ₂ —).)

(Wherein, X ₃ represents a carbon atom, a fluorine atom and a functional group having 1 to 8 carbon atoms including a sulfonyl group (—SO ₂ —).)

(Wherein, X ₄ , X ₅ and X ₆ may be the same or different, and have a C 1-8 functional group containing a carbon atom, a fluorine atom and a sulfonyl group (—SO ₂ —) Represent)

Salts with the anions fluoro group (-F) and sulfonyl group (-SO ₂ -) is stabilized anion to delocalized charge by a strong electron-withdrawing effect, in the composition It exhibits a high degree of dissociation and can achieve high ion conductivity. For this reason, the salt provided with these anions can greatly reduce the electrical resistance value with a small amount of addition, and the decrease in various physical property values in that case is also small. Furthermore, unlike carbon black and the like, since it does not become black and the like even when blended, it can be used for applications requiring transparency and coloring.

The carbon number of the functional group represented by X ₁ to X ₆ in the chemical formula 1, the chemical formula 2 and the chemical formula 3 is 1 to 8, but it is preferably 1 to 4 from the viewpoint of obtaining a higher degree of dissociation It is more preferable that it is -2.
Examples of the functions X ₁ to X ₆ include groups represented by R—SO ₂ — (wherein R represents a hydrocarbon group having 1 to 8 carbon atoms which is substituted by a fluorine atom). Here, examples of the hydrocarbon group having 1 to 8 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, n-pentyl group and isopentyl group, alkyl groups such as tert-pentyl, n-hexyl and 1,1-dimethylpropyl; eg vinyl, allyl, 1-propenyl, isopropenyl, 2-butenyl and 1,3-butadienyl Or alkenyl groups such as 2-pentenyl group; and alkynyl groups such as ethynyl group, 2-propynyl group, 1-butynyl group and 2-butynyl group. The number of fluorine atoms as a substituent and the substitution position are not particularly limited as long as they are in a chemically acceptable range.
Among them, C _n H _m F _{(2 n-m + 1)} -SO _2- (n represents an integer of 1 or more and 8 or less ₎ as the functional groups X ₁ to X ₆ in terms of stability, cost, and handleability; Preferably represents an integer of 0 or more and 16 or less).

It is preferable that the cation which makes a pair with the anion which has the said fluoro group and a sulfonyl group, and comprises a salt is a cation of an alkali metal, group 2A, a transition metal, or an amphoteric metal. Among them, alkali metals are more preferable because they have small ionization energy and easily form stable cations. Furthermore, lithium ions having high conductivity among alkali metals are particularly preferable.

In addition to the metal cations, cations such as those represented by the following Chemical Formula 4 and Chemical Formula 5 can also be used.

(Wherein, R ₁₁ to R ₁₄ each represent an alkyl group having 1 to 20 carbon atoms which may have a substituent, and may be the same or different).

(Wherein, R ₁₅ and R ₁₆ each represent an alkyl group having 1 to 20 carbon atoms which may have a substituent, and may be the same or different).

Examples of the alkyl group having 1 to 20 carbon atoms in the “optionally substituted alkyl group having 1 to 20 carbon atoms” represented by R ₁₁ to R ₁₆ include, for example, methyl, ethyl, n-propyl, Examples include i-propyl, n-butyl, i-butyl, t-butyl, n-pentyl, n-hexyl, n-decyl and the like. As a substituent, for example, halogen (preferably fluorine, chlorine, bromine), oxo group, alkylene oxide group, alkanoyl group (preferably C _1-8 ), alkanoyloxy group (preferably C _1-8 ), alkanoylamino groups (preferably _{C 1 ~} 8), a carboxyl group, an alkoxycarbonyl group (preferably _{C 2 ~} 8), haloalkylcarbonyl groups (preferably _{C 2 ~} 8), alkoxy groups (preferably _{C 1 ~} 8), haloalkoxy groups (preferably _{C 1 ~} 8), an amino group, an alkylamino group (preferably _{C 1 ~} 8), dialkylamino group (preferably _{C 2 ~ 16),} cyclic amino group, alkylaminocarbonyl group (preferably _{C 2 1-8),} a carbamoyl group, a hydroxyl group, a nitro group, a cyano group, a mercapto group, an alkylthio group (preferably _1-8), alkylsulfonyloxy group (preferably _{C 1-8),} alkylsulfonylamino group (preferably include _{C 1-8)} or phenyl group.

As a cation as shown by said Chemical formula 4, three of R ₁₁ to R ₁₄ are methyl groups among others, and the other is an alkyl group having 4 to 20 carbon atoms which may have a substituent. Particularly preferred is a trimethyl type quaternary ammonium cation consisting of Such a trimethyl type quaternary ammonium cation can stabilize a positive charge on a nitrogen atom by three strong electron donating methyl groups, and may have other substituents such as alkyl having 4 to 20 carbon atoms. This is because the groups can improve the compatibility with other components.
Further, in the cation represented by the chemical formula 5, the stronger electron donating property of R ₁₅ or R ₁₆ enhances the stability as a cation by stabilizing the positive charge on the nitrogen atom, and the dissociation degree is further increased. As a result, it is possible to make the salt excellent in conductivity imparting performance. Thus, R ₁₅ or R ₁₆ is preferably an electron donating group, and more preferably a methyl group or an ethyl group.

Among the salts provided with the anion having a fluoro group and a sulfonyl group, bis (trifluoromethanesulfonyl) imidolithium ((CF ₃ SO ₂ ) ₂ NLi), potassium bis (trifluoromethanesulfonyl) imide ((CF ₃ ), among others SO ₂ ) ₂ NK) or lithium trifluorosulfonate (CF ₃ SO ₃ Li) is preferred. These salts are stable even at very high temperatures, and unlike perchlorates conventionally used as ion conductive agents, no treatment such as explosion proof specifications is required, and other physical properties are particularly improved. It is difficult to make it worse, and it is also excellent in reducing the rise in resistance under low temperature and low humidity. From these points, it is possible to further improve the performance as the ion conductive agent by reducing the manufacturing cost and securing the safety.

In addition, as salts provided with anions having a fluoro group and a sulfonyl group, (C ₂ F ₅ SO ₂ ) ₂ NLi, (C ₄ F ₉ SO ₂ ) (CF ₃ SO ₂ ) NLi, (FSO ₂ C ₆₎ F ₄ ) (CF ₃ SO ₂ ) NLi, (C ₈ F ₁₇ SO ₂ ) (CF ₃ SO ₂ ) NLi, (CF ₃ CH ₂ OSO ₂ ) ₂ NLi, (CF ₃ CF ₂ CH ₂ OSO ₂ ) ₂ NLi , (HCF ₂ CF ₂ CH ₂ OSO ₂ ) ₂ NLi, ((CF ₃ ) ₂ CHOSO ₂ ) ₂ NLi, (CF ₃ SO ₂ ) ₃ CLi, (CF ₃ CH ₂ OSO ₂ ) ₃ CLi, C ₄ F ₉ SO ₃ Li, (C ₂ F ₅ SO ₂ ) ₂ NK, (C ₄ F ₉ SO ₂ ) (CF ₃ SO ₂ ) NK, (FSO ₂ C ₆ F ₄ ) (CF ₃ SO ₂ ) NK, (C ₈ F _{1 SO 2) (CF 3 SO 2} ) NK, (CF 3 CH 2 OSO 2) 2 NK, (CF 3 CF 2 CH 2 OSO 2) 2 NK, (HCF 2 CF 2 CH 2 OSO 2) 2 NK, (( CF ₃ ) ₂ CHOSO ₂ ) ₂ NK, (CF ₃ SO ₂ ) ₃ CK, (CF ₃ CH ₂ OSO ₂ ) ₃ CK, C ₄ F ₉ SO ₃ K, etc. are also mentioned as suitable examples.
In the present invention, as the salt provided with the anion having the fluoro group and the sulfonyl group, one kind of compounds as exemplified above may be used alone, or plural kinds may be used in combination.

The salt provided with the anion having a fluoro group and a sulfonyl group is preferably blended in a ratio of 0.5 to 20 parts by mass with respect to 100 parts by mass of the EO-PO-AGE copolymer. If the blending amount of the salt is less than 0.5 parts by mass, sufficient conductivity can not be obtained. On the other hand, the conductivity hardly changes even if the salt is added at a certain level or more. Therefore, when the blending amount of the salt is more than 20 parts by mass, the disadvantage that the cost increases compared to the effect of conductivity improvement It is for.

In the present invention, a part of the ions generated from the salt to be added can be single-ionized using an anion adsorbent or the like to stabilize the conductivity and improve the conductivity when a small amount is added.
As the anion adsorbent, synthetic hydrotalcite mainly composed of Mg and Al, an inorganic ion exchanger such as Mg-Al-based, Sb-based, Ca-based or the like, and an ion seat for fixing anions in the chain (co ) Known compounds such as polymers are useful. Specifically, synthetic hydrotalcite (Kyowa Chemical Industry Co., Ltd. “Kyoward-2000”, “Kyoward-1000”), anion exchange ion exchange resin (Nippon Shimizu Co., Ltd. “Dionone DCA11” Etc.).

In the present invention, it is preferable to further add a compatibilizer to the dynamically crosslinked thermoplastic elastomer composition described above. By blending the compatibilizer, the dispersibility of each component in the dynamically cross-linked thermoplastic elastomer composition, in particular, the rubber component and the thermoplastic resin and / or the thermoplastic elastomer is improved, and thus excellent moldability is obtained. be able to.
As the compatibilizer, known compatibilizers used in the relevant field may be used, but ethylene-acrylic acid ester-glycidyl methacrylate copolymer or ethylene-acrylic acid ester-maleic anhydride copolymer is blended. Is preferred.

As acrylic acid ester in ethylene-acrylic acid ester-glycidyl methacrylate copolymer or ethylene-acrylic acid ester-maleic anhydride copolymer, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, acrylic acid 2 And esters of acrylic acid and alcohol such as ethylhexyl and the like, and among them, methyl acrylate and ethyl acrylate are preferable.
The content of the acrylic ester component is preferably 0.1 to 30% by mass, more preferably 1 to 20% by mass, and still more preferably 5 to 15% by mass. The content of glycidyl methacrylate or maleic anhydride is preferably 0.05 to 20% by mass, more preferably 0.1 to 15% by mass, and still more preferably 0.5 to 10% by mass. Preferably, it is 1 to 10% by mass.

The blending amount of the above-mentioned compatibilizer is preferably 1 to 20 parts by mass with respect to 100 parts by mass of the rubber component in the elastomer composition.
If the blending amount of the compatibilizer is less than 1 part by mass, the effect as the compatibilizer is not sufficient, and the rubber component, the thermoplastic resin and / or the thermoplastic elastomer, the EO-PO-AGE copolymer, the salt Is not well mixed, and the uniformity of the composition is impaired, so that the processability is deteriorated. On the other hand, if the compounding amount of the compatibilizer exceeds 20 parts by mass, the compatibilization effect is saturated, so the improvement is not further improved, and conversely, the demerit such as the increase in hardness is increased.

In the present invention, the above-mentioned dynamically crosslinked thermoplastic elastomer composition is molded into various shapes to obtain a conductive molded article. Among them, forming into a roll, a sheet or a seamless belt is preferable.
As a molding method, extrusion molding is used. This is because, if extrusion molding is used, the surface can be processed smoothly and continuous molding can be performed, so that mass productivity is excellent.

The conductive molded article of the present invention is simple in structure having only one conductive layer comprising the above-mentioned dynamically crosslinked thermoplastic elastomer composition, and is preferable from the viewpoint of industrial production. However, in addition to the conductive layer, a multilayer structure of two or three layers may be used to adjust the electrical resistance, etc. According to the required performance, the type of each layer, the lamination order, the lamination thickness, etc. should be set appropriately. Can. Among them, the conductive layer is preferably the outermost layer.

The present invention is characterized in that the surface of the conductive molded article is subjected to an ultraviolet irradiation treatment.
As described above, by forming the oxide film by irradiating the surface portion of the conductive molded article with ultraviolet light, the oxide film becomes a dielectric layer, and the dielectric loss tangent of the conductive molded article can be reduced. When used as a member, the chargeability can be added to the toner, and the added chargeability can be maintained. Then, it is preferable to form the oxide film by ultraviolet irradiation because the processing time is short and the cost is low.
The said ultraviolet irradiation process can be performed according to a well-known method. For example, although it changes with the distance of the surface of an electroconductive molded article, and an ultraviolet lamp, the kind of rubber component, etc., the wavelength is 100-400 nm, More preferably, ultraviolet light of 100-300 nm is 30 seconds-30 minutes, Preferably 1 minute-10 Irradiation for about a minute is preferable. Then, in the case of a roll, irradiation is performed while rotating, so that the entire surface of the conductive molded article is irradiated with ultraviolet rays uniformly.

The conductive molded article of the present invention thus obtained has properties of low hardness and reduced surface adhesion. As an index thereof, the conductive molded article of the present invention has a Shore A hardness of 80 or less and 40 or more according to JIS K6253 under conditions of a temperature of 23 ° C. and a humidity of 55%, and for a sheet made of polybutylene terephthalate (PBT). The friction coefficient is preferably 1.0 or less and 0.3 or more.
When the Shore A hardness is more than 80, it is too hard, and when it is less than 40, it is too soft, and the range of application of the conductive molded article of the present invention is narrowed. When the coefficient of friction with respect to a sheet produced by PBT exceeds 1.0, the surface is highly adhesive, and problems such as toner adhesion and deterioration in durability tend to occur.

The electroconductive molded article of the present invention can be used in various applications as long as the application requires conductivity. In particular, it can be very suitably used as a conductive member of an image forming apparatus such as a printer, an electrostatic copying machine, a facsimile machine, an ATM or the like.
Specifically, for example, in the case of a roll-shaped conductive molded product, a charging roller for charging the photosensitive drum uniformly, a developing roller for adhering the toner to the photosensitive member, a toner image from the photosensitive member etc. A transfer roller for transferring to a transfer belt or the like, a toner supply roller for conveying toner, a drive roller for driving the transfer belt from the inside, a paper feed roller contributing to conveyance of paper (more specifically, paper feed It is used as a sheet feeding roller, a conveying roller, a sheet discharging roller, etc. constituting the mechanism, and a cleaning roller for removing the remaining toner.
The sheet-like conductive molded article is preferably used as, for example, a conductive sheet or an antistatic film attached to an image forming apparatus.
The seamless belt-like conductive molded product is used as a conveying belt, a transfer belt, an intermediate transfer belt, a fixing belt, a developing belt, a belt for a photosensitive substrate, and the like.

In the conductive molded article of the present invention, the surface is subjected to an ultraviolet irradiation treatment to reduce the surface tackiness while maintaining the hardness low. As a result, there is no concern of bleeding such as a softener, the occurrence of defects due to toner adhesion is suppressed, and the abrasion resistance is also improved.

In the conductive molded article of the present invention, the electric resistance is effectively reduced by blending a salt having an anion having a fluoro group and a sulfonyl group as an ion conductive agent together with the EO-PO-AGE copolymer. can do. Therefore, since the compounding amount of the ion conductive agent can be smaller than the conventional one, the variation of the electric resistance is also small, and problems such as occurrence of bleeding or deterioration of mechanical properties such as compression set and hardness can be prevented. Furthermore, the cost of raw materials can be reduced.

In the conductive molded article of the present invention, since the rubber component in which EPDM and NBR are blended is dynamically crosslinked and dispersed in the mixture of one or both of the thermoplastic resin and the thermoplastic elastomer, it is like rubber. Durability, elasticity, flexibility and moldability such as resin. Furthermore, the conductive moldings of the invention are thermoplastic and recyclable.

The preferred embodiments of the dynamically crosslinked thermoplastic elastomer composition constituting the conductive molded article of the present invention will be described below.
The rubber components include EPDM and NBR. The compounding amount is EPDM: NBR = 100: 0 to 10:90. If the proportion of EPDM is 50% by mass or more, preferably 80% by mass or more, more preferably 95 to 100% by mass in the entire rubber component, the weatherability of the conductive molded article of the present invention can be enhanced. In some cases it is effective to increase the proportion of EPDM. The reason is that EPDM rubber has a saturated hydrocarbon main chain and does not contain a double bond in the main chain, so molecular backbone cleavage occurs even when exposed to a high concentration ozone atmosphere or environment such as light irradiation for a long time It is difficult.

The rubber component is dynamically crosslinked and dispersed in the thermoplastic resin. As a thermoplastic resin, it is preferable to use an olefin resin, and it is more preferable to use a polypropylene.
The thermoplastic resin is preferably contained in a proportion of 2 to 100 parts by mass, more preferably 5 to 50 parts by mass, and more preferably 10 to 40 parts by mass with respect to 100 parts by mass of the rubber component. More preferably, it is contained in the ratio of

The rubber component may be dynamically crosslinked and dispersed in a mixture of thermoplastic resin and thermoplastic elastomer.
As a thermoplastic resin, it is preferable to use an olefin resin, and it is more preferable to use a polypropylene.
As the thermoplastic elastomer, a styrene-based thermoplastic elastomer is preferably used, and a styrene-ethylene-ethylene / propylene-styrene copolymer (SEEPS) is more preferably used.
The mixing ratio of the styrene-based thermoplastic elastomer and the olefin-based resin is 30 to 50 parts by mass of the olefin-based resin with respect to 100 parts by mass of the styrene-based thermoplastic elastomer.
The mixture of the thermoplastic elastomer and the thermoplastic resin is preferably contained in a proportion of 20 to 120 parts by mass with respect to 100 parts by mass of the EPDM rubber, and more preferably in a proportion of 40 to 100 parts by mass. Preferably, the content is further preferably 50 to 90 parts by mass.

The rubber component is dynamically crosslinked by the crosslinking agent. As a crosslinking agent, a resin crosslinking agent or a peroxide etc. are mentioned, for example. Among them, it is preferable to use a resin crosslinking agent.

As a resin crosslinking agent, a phenol resin, a melamine formaldehyde resin, a triazine formaldehyde condensate, a hexamethoxymethyl melamine resin etc. are mentioned, for example. Among them, it is preferable to use a phenol resin.
Specific examples of the phenol resin include various phenol resins synthesized by the reaction of a phenol such as phenol, alkylphenol, cresol, xylenol or resorcin and an aldehyde such as formaldehyde, acetaldehyde or furfural. It is also possible to use a halogenated phenol resin in which at least one halogen atom is bonded to an aldehyde unit of the phenol resin.
In particular, an alkylphenol-formaldehyde resin obtained by the reaction of an alkylphenol having an alkyl group bonded to the ortho position or para position of benzene and formaldehyde is excellent in compatibility with rubber and is rich in reactivity, and the crosslinking reaction start time is It is preferable because it can be done relatively quickly. The alkyl group of the alkylphenol-formaldehyde resin is usually an alkyl group having 1 to 10 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, a propyl group and a butyl group. In addition, halides of this alkylphenol-formaldehyde resin are also suitably used.
Furthermore, a modified alkylphenol resin obtained by addition condensation of sulfurized-p-tert-butylphenol and an aldehyde, or an alkylphenol-sulfide resin can also be used as a resin crosslinking agent.

The compounding amount of the resin crosslinking agent is preferably 2 to 20 parts by mass with respect to 100 parts by mass of the rubber component. This is because if the compounding amount of the resin crosslinking agent is less than 2 parts by mass, the crosslinking becomes insufficient and the abrasion resistance and the like become poor, while if the compounding amount of the resin crosslinking agent exceeds 20 parts by mass, the conductivity of the present invention This is because the hardness of the molded article may be too high. The blending amount is more preferably 5 to 20 parts by mass, further preferably 5 to 15 parts by mass.

A coagent may be used to appropriately carry out the dynamic crosslinking reaction. As the coagent, metal oxides are used, and zinc oxide and zinc carbonate are particularly preferred.
The blending amount of the crosslinking aid is preferably 0.5 to 10 parts by mass, and more preferably 1 to 10 parts by mass with respect to 100 parts by mass of the rubber component.

The peroxide is not particularly limited as long as it is a compound capable of crosslinking the rubber component, and examples thereof include benzoyl peroxide, 1,1-bis (tert-butylperoxy) -3,3,5-trimethylcyclohexane, 2,5 -Dimethyl-2,5-di (benzoylperoxy) hexane, di (tert-butylperoxy) diisopropylbenzene, 1,4-bis [(tert-butyl) peroxyisopropyl] benzene, di (tert-butylperoxy) ) Benzoate, tert-butyl peroxybenzoate, dicumyl peroxide, tert-butyl cumyl peroxide, 2,5-dimethyl-2,5-di (tert-butyl peroxy) hexane, di tert-butyl peroxide or 2 5, 5-Dimethyl-2, 5-di (tert-butyl) Peroxy) -3-hexene, and the like. One of these may be used alone, or two or more of these may be used in combination.

The compounding amount of the peroxide is preferably 0.2 to 3.0 parts by mass with respect to 100 parts by mass of the rubber component. This is because if the compounding amount of the peroxide is less than 0.2 parts by mass, the crosslinking of the rubber component becomes insufficient and the abrasion resistance etc. is inferior, while the compounding amount of the peroxide is 3.0 parts by mass In addition to the decrease in physical properties due to molecular scission, dispersion failure etc. occur and processing becomes difficult.
The lower limit of the peroxide content is more preferably 0.5 parts by mass or more and particularly preferably 1.0 parts by mass or more with respect to 100 parts by mass of the rubber component. Moreover, 2.5 mass parts or less are preferable with respect to 100 mass parts of rubber components, and, as for an upper limit, 2.0 mass parts or less are especially preferable.

A co-crosslinking agent may be blended with the peroxide. The co-crosslinking agent acts to crosslink itself as well as to react with the rubber molecules to crosslink and polymerize the whole. By co-crosslinking with this co-crosslinking agent, the molecular weight of the cross-linked molecule can be increased to improve the abrasion resistance and the like.
As the co-crosslinking agent, for example, functional groups of polyfunctional monomers, metal salts of methacrylic acid or acrylic acid, methacrylic esters, aromatic vinyl compounds, heterocyclic vinyl compounds, allyl compounds, and 1,2-polybutadiene are used. Polyfunctional polymers, dioximes and the like can be mentioned.
When the co-crosslinking agent is blended with the peroxide, the blending amount of the co-crosslinking agent can be appropriately selected in relation to the type of co-crosslinking agent or other components to be used, but based on 100 parts by mass of the rubber component Preferably, it is 5 parts by mass or more and 20 parts by mass or less, more preferably 10 parts by mass or more and 15 parts by mass or less.

An elastomer composition in which a rubber component containing EPDM and NBR in a specific ratio described above is dynamically crosslinked and dispersed in a thermoplastic resin or a mixture of a thermoplastic resin and a thermoplastic elastomer, EO-PO- By blending an AGE copolymer and a salt having an anion having a fluoro group and a sulfonyl group, a conductive, dynamically crosslinked thermoplastic elastomer composition is obtained.

As an EO-PO-AGE copolymer, EO-PO-AGE co-weight in which the content ratio of ethylene oxide: propylene oxide: allyl glycidyl ether is 80 to 95 mol%: 1 to 10 mol%: 1 to 10 mol% It uses union. It is particularly preferable that the number average molecular weight Mn of the copolymer is 50,000 or more.
The blending amount of the EO-PO-AGE copolymer is preferably 3 to 20 parts by mass, and more preferably 5 to 15 parts by mass with respect to 100 parts by mass of the rubber component.

As a salt provided with an anion having a fluoro group and a sulfonyl group, a salt provided with an anion represented by the above-mentioned chemical formula 1 or 2 is preferable, and in particular, it is represented by X ₁ to X ₃ in the chemical formula 1 or 2. More preferred are salts with anions where the functional group is CF ₃ SO _2- .
It is preferable that the cation which makes a pair with the anion in the said salt and comprises a salt is an alkali metal, and lithium ion is more preferable among them. Specifically, bis (trifluoromethanesulfonyl) imide lithium is particularly preferable as the salt.
The salt provided with the anion having a fluoro group and a sulfonyl group is blended in a ratio of 1 to 20 parts by mass with respect to 100 parts by mass of the EO-PO-AGE copolymer. Preferably, the proportion is 5 to 15 parts by mass.

The dynamically crosslinked thermoplastic elastomer composition constituting the conductive molded article of the present invention preferably further contains a compatibilizer. The compounding amount of the compatibilizer is preferably 3 to 15 parts by mass, and more preferably 5 to 10 parts by mass with respect to 100 parts by mass of the EPDM rubber.

As the compatibilizer, it is preferable to use ethylene-acrylic acid ester-glycidyl methacrylate copolymer or ethylene-acrylic acid ester-maleic anhydride copolymer, and use ethylene-acrylic acid ester-maleic anhydride copolymer Is more preferred.
In the ethylene-acrylic acid ester-maleic anhydride copolymer, methyl acrylate or ethyl acrylate is used as the acrylic acid ester, and in particular, it is preferable to use ethyl acrylate. The proportions of the constituent monomers are such that the acrylic ester content is 3 to 10% by mass, and the maleic anhydride content is 1 to 5% by mass. In the copolymer, the melt flow rate is preferably 0.5 to 100 g / 10 min, and more preferably 1 to 50 g / 10 min.

As the compatibilizer, one or two or more of the terpolymers falling under the following definition may be used together with any of the above-mentioned two types of copolymers.
The terpolymer as a compatibilizer is a terpolymer comprising an olefin component (c1), an acrylic ester or methacrylic ester (c2) and an unsaturated carboxylic acid unit (c3).
Examples of the olefin component (c1) include ethylene-based hydrocarbons having 2 to 6 carbon atoms such as ethylene, propylene, isobutylene, 1-butene, 1-pentene and 1-hexene.
Specific examples of the acrylic ester or methacrylic ester (c2) component include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, butyl methacrylate, acrylic Mention may be made of esters of acrylic acid or methacrylic acid with alcohols, such as 2-ethylhexyl acid, 2-ethylhexyl methacrylate and the like, among which methyl acrylate, methyl methacrylate, ethyl acrylate and ethyl methacrylate are preferred.
The unsaturated carboxylic acid unit (c3) is introduced by unsaturated carboxylic acid or its anhydride, and specifically, acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic acid, fumaric acid, croton Besides acids and the like, half esters of unsaturated dicarboxylic acids, half amides and the like can be mentioned. Among them, acrylic acid, methacrylic acid, maleic acid and maleic anhydride are preferable, and in particular, maleic anhydride is preferable. The form of the unsaturated carboxylic acid unit is not limited as long as it is copolymerized in the terpolymer, and examples thereof include random copolymerization, block copolymerization, graft copolymerization and the like.
The content of the acrylic ester or methacrylic ester (c2) component is preferably 0.1 to 30% by mass, more preferably 1 to 20% by mass, and still more preferably 5 to 15% by mass. . The content of unsaturated carboxylic acid unit (c3) is preferably 0.05 to 20% by mass, more preferably 0.1 to 15% by mass, and still more preferably 0.5 to 10% by mass. It is more preferable, and 1 to 10% by mass is particularly preferable.

The dynamically crosslinked thermoplastic elastomer composition constituting the conductive molded article of the present invention may be blended with other components in addition to the above components as long as the object of the present invention is not violated.
For example, a softener may be blended to provide adequate flexibility and elasticity.
The softeners include oils and plasticizers. As the oil, it is possible to use, for example, mineral oils such as paraffinic, naphthenic and aromatic oils, synthetic oils per se known per se comprising hydrocarbon oligomers, or process oils. As a synthetic oil, for example, an oligomer with α-olefin, an oligomer of butene, and an amorphous oligomer of ethylene and α-olefin are preferable. Examples of the plasticizer include phthalate type, adipate type, sepacate type, phosphate type, polyether type and polyester type plasticizers, and more specifically, for example, dioctyl phthalate (DOP), dibutyl phthalate (DBP), dioctyl Sepacate (DOS), dioctyl adipate (DOA) and the like. Among them, paraffinic oil is preferable as the softener, and paraffin process oil is more preferable.

When the softener is blended, the blending amount is 50 to 250 parts by mass with respect to 100 parts by mass of the rubber component in the dynamically crosslinked thermoplastic elastomer composition. The amount is preferably 50 to 200 parts by mass, and particularly preferably 70 to 150 parts by mass.
When the blending amount of the softener is less than the above range, the effect of adding the softener, that is, the effect of further improving the dispersibility of the rubber component at the time of dynamic crosslinking is hardly obtained, and the hardness also tends to be high. On the other hand, when the amount of the softener is more than the above range, the softener causes crosslinking inhibition and the dynamic crosslinking is not sufficiently performed, so that the physical properties are easily deteriorated and the softener is easily bled. In addition, the amount of the extender oil at the time of using oil extended rubber as a rubber component is contained in the compounding quantity of the said softener.

In addition, a filler or the like may be blended to improve the mechanical strength.
Examples of the filler include powders of silica, carbon black, clay, talc, calcium carbonate, dibasic phosphite (DLP), basic magnesium carbonate, alumina and the like.
The filler is preferably compounded in an amount of 15% by mass or less based on the total mass of the dynamically crosslinked thermoplastic elastomer composition. Although this is effective in improving the tensile strength, tear strength and the like of the composition, the addition of the filler tends to lower the flexibility of the composition if it is incorporated too much.

In addition, additives such as an antioxidant, an antioxidant, an ultraviolet light absorber, a lubricant, a pigment, an antistatic agent, a flame retardant, a neutralizing agent, a nucleating agent, and an antifoaming agent may be appropriately blended.

The conductive molded article of the present invention can be manufactured by a known method, and specifically, for example, the following manufacturing method is mentioned as a preferred embodiment.
First, a dynamically crosslinked thermoplastic elastomer composition constituting the conductive molded article of the present invention is produced.
It does not specifically limit as a preparation method of the said composition, A well-known method can be used. All of the components contained in the composition may be kneaded at once, or some of the components may be kneaded beforehand and then the remaining components may be kneaded in two or more stages, such as in stages. It is also good. However, it is preferable to produce by the following method.

First, the rubber component, a mixture of one or both of a thermoplastic resin and a thermoplastic elastomer, and a crosslinking agent are kneaded, and the rubber component is dynamically crosslinked with the crosslinking agent to obtain thermoplastic resin and thermoplastic elastomer Disperse in one or both mixtures.
The heating temperature for dynamic crosslinking is preferably 160 to 250 ° C., and the heating time is preferably 1 to 20 minutes. For dynamic crosslinking, a twin-screw extruder, a Banbury mixer, a kneader or the like can be used.
The dynamic crosslinking may be performed in the presence of a halogen such as chlorine, bromine, fluorine or iodine. In order to cause a halogen to be present at the time of dynamic crosslinking, the above-described halogenated resin crosslinking agent may be used, or a halogen donating substance may be blended. Examples of the halogen donating substance include tin chloride such as stannic chloride, ferric chloride, cupric chloride and the like. As the halogen donating substance, one substance may be used alone, or two or more substances may be used in combination.

Separately, the EO-PO-AGE copolymer is kneaded with a salt having an anion having a fluoro group and a sulfonyl group. The heating temperature during mixing is preferably 50 to 150 ° C., and the heating time is preferably 1 to 20 minutes. A twin-screw extruder, a Banbury mixer, a kneader, etc. can be used for kneading | mixing.

The obtained elastomer composition, the obtained conductive composition, and optionally the compatibilizer and other additives may be added and kneaded to produce a conductive, dynamically crosslinked thermoplastic elastomer composition. . The heating temperature at the time of kneading is preferably 160 to 250 ° C., and the heating time is preferably 1 to 20 minutes. A twin-screw extruder, a Banbury mixer, a kneader, etc. can be used for kneading | mixing.
The resulting composition may be pelletized for later processing. Thereby, good moldability can be obtained.

The conductive composition is characterized in that it does not easily enter the dynamically crosslinked domain phase, and is selectively mixed in the matrix phase. For this reason, according to the manufacturing method, the conductive composition is selectively disposed in the matrix of the elastomer composition, and the thermoplastic resin and / or the thermoplastic elastomer in which the conductive composition is a matrix It can be unevenly distributed. As a result, even when the conductive composition is blended, the degree of crosslinking of the rubber is not affected, and therefore, the increase in compression set can be suppressed. At the same time, the amount of salt used is not unnecessarily increased, so that the increase in hardness can be suppressed, and the cost of raw materials can also be suppressed.

The obtained dynamically crosslinked thermoplastic elastomer composition is introduced into a resin extruder and extruded into a seamless belt, sheet or roll, preferably a sheet or roll. The extrusion method is preferably used in that it can be manufactured continuously and that the productivity can be considerably improved without the need for a polishing step.

Specifically, when the conductive molded article of the present invention is in the form of a roll, the dynamically crosslinked thermoplastic elastomer composition is extruded into a tubular form using a single screw extruder under the conditions of 150 to 250 ° C. A roll-shaped conductive molded article can be obtained by press-fitting the core metal or by bonding and fixing both with an adhesive. The core metal may be made of metal such as aluminum, aluminum alloy, SUS or iron, ceramic, or the like. A substantially D-shaped rubber roller can also be obtained by press-fitting a substantially D-shaped core material into the hollow portion of the roll portion formed into a cylindrical shape.
When the electroconductive molded article of the present invention is in the form of a sheet, the electroconductive molded article in the form of a sheet can be obtained by extruding the dynamically crosslinked thermoplastic elastomer composition into a sheet using a resin extruder under the conditions of 150 to 250 ° C. can get.

After molding, processing such as polishing may be applied if desired.
The conductive molded article of the present invention can be obtained by irradiating the surface of the obtained molded article with ultraviolet light.
Specifically, when the conductive molded article of the present invention is in the form of a roll, an ultraviolet irradiator is used, and the distance between the roll and the ultraviolet lamp is 10 cm. Is irradiated for 5 minutes and the roll is rotated four times so that ultraviolet rays can be irradiated on the entire circumference (360 degrees) of the roll to form an oxide film.
When the conductive molded article of the present invention is in the form of a sheet, an oxide film is formed by irradiating ultraviolet rays (wavelengths 184.9 nm and 253.7 nm) for 10 minutes using an ultraviolet irradiator and setting the distance between the sheet and the ultraviolet lamp to 30 cm. be able to.

The conductive molded article of the present invention thus obtained has low hardness and low surface adhesion. Specifically, the conductive molded article of the present invention preferably has a Shore A hardness of 40 or more and 70 or less, and 45 or more and 60 or less under JIS K6253 under conditions of a temperature of 23 ° C. and a humidity of 55%. The coefficient of friction with respect to a sheet made of polybutylene terephthalate (PBT) is preferably 0.3 or more and 1.0 or less, and more preferably 0.3 or more and 0.8 or less.

"Example"
Examples and comparative examples are shown to describe the present invention in detail.
A sheet-like conductive molded article is produced using the composition shown in Table 1 below, and evaluation of extrusion processability, hardness and coefficient of friction is carried out by the method described later for the obtained conductive molded article. went. The evaluation results are shown in Tables 1 and 2.

The following products were used for each component in the table.
・ EPDM rubber; "Esprene 505A" manufactured by Sumitomo Chemical Co., Ltd.
・ NBR; Nippon Zeon Co., Ltd. “Nipol DN401LL”
-Thermoplastic resin; polypropylene ("Novatec PP" manufactured by Japan Polypropylene Corp.)
-Thermoplastic elastomer; styrenic thermoplastic elastomer ("Septon 4077" manufactured by Kuraray Co., Ltd.)
・ Softening agent: Paraffinic process oil (Idemitsu Kosan Co., Ltd. “Diana Process Oil PW-380”)
Crosslinker; Phenolic resin crosslinker (Takashiru 250-III, manufactured by Taoka Chemical Industry Co., Ltd.)
-Crosslinking auxiliary agent: Zinc flower ("Zinc flower No. 1" manufactured by Mitsui Mining & Smelting Co., Ltd.)
・ EO-PO-AGE copolymer; Nippon Zeon Co., Ltd. “Zeospan 8100”
Salt: bis (trifluoromethanesulfonyl) imide lithium ethylene-acrylic acid ester-maleic anhydride copolymer; "bondine LX 4110" manufactured by Arkema Co., Ltd.

A conductive molded article was produced in the following steps.
Pelletized EPDM, NBR, thermoplastic resin, thermoplastic elastomer, softener, crosslinking agent, and crosslinking aid in the proportions described in the above table, dry-blended with a tumbler, and then using a twin-screw extruder (IPEC The rubber component was dynamically crosslinked by kneading at a rotation speed of 200 rpm and a temperature of 200 ° C., and a pellet of an elastomer composition dispersed in a thermoplastic resin and / or a thermoplastic elastomer was produced.
Separately, a pellet-like EO-PO-AGE copolymer, and a salt provided with an anion having a fluoro group and a sulfonyl group are dry-blended with a tumbler, and then a twin screw single screw extruder (type 2TR-75 made by Moriyama) And extruded at a temperature of 70 ° C. and pelletized.

Pellets of the obtained elastomer composition, pellets of the separately obtained conductive composition, and in Example 7 and Comparative Examples 5 and 6, ethylene-acrylic acid ester-maleic anhydride copolymer in the proportions described in the above Table And dry blending in a tumbler, followed by kneading at a rotation speed of 200 rpm and a temperature of 200 ° C. with a twin screw extruder (“HTM38” manufactured by I-PAC) to obtain pellets of a dynamically crosslinked thermoplastic elastomer composition .

The pellets of the dynamically crosslinked thermoplastic elastomer composition thus obtained were charged into a resin extruder and extruded into a sheet of 2 mm in thickness to obtain a conductive molded article.
Furthermore, in Examples 1 to 7, the surface of the conductive molded article obtained was irradiated with ultraviolet light. Specifically, ultraviolet rays (wavelengths 184.9 nm and 253.7 nm) are irradiated for 10 minutes using an ultraviolet irradiator (“PL21-200” manufactured by Sen Special Light Source Co., Ltd.) with a distance of 30 cm between the sheet and the ultraviolet lamp. did.

The test method of a conductive molded article is shown.
(Extrusion processability)
The shape of the sheet (rubber surface) when the pellets of the dynamically crosslinked thermoplastic elastomer composition were extruded into a sheet by a resin extruder was visually evaluated.
凹凸; The surface asperities are very fine and visually appear to be glossy. The surface is smooth and there is no problem at all.
○: There are small irregularities on the surface, the surface is smooth and no problem.
X: Unevenness of the surface is very large and the sheet can not be produced because it is cut off during extrusion.

(hardness)
According to JIS K6253, it measured on the constant temperature and humidity conditions of 23 degreeC of atmospheric temperature, and 55% of relative humidity.

(Coefficient of friction)
The extruded sheet-like conductive molded product was cut into a strip having a width of 15 mm and a length of 50 mm in the extrusion direction to prepare a sample.
The coefficient of friction of the above sample and polybutylene terephthalate (PBT) sheet was measured using a surface property measuring machine ("HEIDON-14 type" manufactured by Shinto Scientific Co., Ltd.) under a load of 200 gf and a speed of 3,000 mm / min. .
The measurement was performed 5 times, and the average value was made into the coefficient of friction.

In Comparative Examples 1 to 3 in which the surface was not irradiated with ultraviolet light, it was found that the coefficient of friction against the sheet made of PBT was 1.22 to 1.35, and the adhesive force of the surface was high.
In Comparative Example 4 in which only NBR is contained as a rubber component, the extrusion processability is inferior so that a sheet can not be formed, and it can be seen that NBR as a rubber component causes a dispersion failure in a thermoplastic resin. And as shown to the comparative example 5, even if it mix | blends a compatibilizer, it is understood that the dispersion | distribution defect of NBR is not eliminated but it is still inferior to extrusion processability. Further, as shown in Comparative Example 6, even when EPDM: NBR = 3: 97 is blended slightly, the dispersion failure of NBR is not resolved and it is understood that the extrusion processability is still inferior.

On the other hand, Examples 1 to 7 are excellent in extrusion processability and hardness is sufficiently low, and in addition, it is understood that the surface adhesive force is reduced to 1.0 or less with the coefficient of friction to the sheet made of PBT. .

Claims (5)

1. The rubber component prepared by blending ethylene-propylene-diene copolymer rubber (EPDM) and acrylonitrile butadiene rubber (NBR) at EPDM: NBR = 100: 0 to 5:95 is either one of thermoplastic resin and thermoplastic elastomer or In the elastomer composition which is dynamically crosslinked and dispersed in both mixtures,
   A conductive, dynamically crosslinked thermoplastic elastomer composition obtained by blending an ethylene oxide-propylene oxide-allyl glycidyl ether (EO-PO-AGE) copolymer and a salt having an anion having a fluoro group and a sulfonyl group. ,
   A conductive molded article, wherein the surface of the sheet-like or roll-like molded article of the dynamically crosslinked thermoplastic elastomer composition is subjected to ultraviolet irradiation treatment.
2. The dynamically crosslinked thermoplastic elastomer composition further contains an ethylene-acrylic acid ester-glycidyl methacrylate copolymer or an ethylene-acrylic acid ester-maleic anhydride copolymer as a compatibilizing agent. The electroconductive molded article according to
3. Shore A hardness of JIS K6253 under conditions of temperature 23 ° C. and humidity 55% is 80 or less and 40 or more,
   The conductive molded article according to claim 1 or 2, wherein the friction coefficient with respect to a sheet made of polybutylene terephthalate (PBT) is 1.0 or less and 0.3 or more.
4. The electroconductive molded article according to any one of claims 1 to 3, comprising an electroconductive sheet or an electroconductive roller attached to the image forming apparatus.
5. It is a manufacturing method of the electroconductive molded article of any one of Claim 1 thru | or 4, Comprising:
   The rubber component, a mixture of one or both of a thermoplastic resin and a thermoplastic elastomer, and a crosslinking agent are kneaded, and the rubber component is dynamically crosslinked by the crosslinking agent to form one or both of the thermoplastic resin and the thermoplastic elastomer. Dispersed in a mixture of the above to make the thermoplastic elastomer composition,
   Providing a mixture of the EO-PO-AGE copolymer and the salt,
   The kneaded product is kneaded with the thermoplastic elastomer composition to form the conductive, dynamically crosslinked thermoplastic elastomer composition,
   The dynamically crosslinked thermoplastic elastomer composition is charged into a resin extruder to obtain the sheet-like or roll-like shaped article,
   A method of producing a conductive molded article, characterized in that the surface of the molded article is irradiated with ultraviolet light.