JP6913302B2 - Semi-conductive rubber composition - Google Patents

Description

The semi-conductive rubber composition of the present invention and the semi-conductive rubber material using the semi-conductive rubber composition are capable of developing, charging, transferring, etc. in electrophotographic processes in copiers, printers, etc. due to their semi-conductive properties. It is used for members used for semi-conductive rollers or belts.

In recent years, in the charging rolls, transfer rolls, and developing rolls used in the contact charging method, there is a demand for further improvement of the physical properties of the rubber material in the base material portion due to the demand for higher image quality and higher speed. Hereinafter, the use of the electrophotographic equipment will be described as an example of the semi-conductive member, but the present invention is not limited to the use of the electrophotographic equipment.

Due to the demand for high image quality and high speed, semi-conductive rubber materials such as rubber charging rolls and transfer rolls of electrophotographic copying machines are required to satisfy the following conditions.
(1) The measurement environment has semi-conductive characteristics under low temperature and low humidity and high temperature and high humidity.
(2) Since it is preferable that the printing characteristics do not change even under low temperature and low humidity and high temperature and high humidity, the environmental resistivity of the volume resistivity is small.
(3) The contaminants of the photoconductor are smaller for the members, charging rolls, transfer rolls, etc. that come into direct contact with the photoconductor.

Further, in the case of the method in which the developing roll is brought into direct contact with the surface of the photoconductor drum to form a toner image on the surface of the photoconductor drum, low hardness is required as a characteristic of the developing roll. It is known that even if the contact portion is deformed by increasing the rebound resilience of the rubber layer, it can be quickly restored to the original shape because there is a problem that the pressure contact portion with the photoconductor drum is settled. Patent Document 1).

Further, in the case of a semi-conductive rubber material using a polyether polymer obtained by polymerizing an oxylan compound, the semi-conductive rubber material crosslinked with an organic peroxide is semi-conductive by vulcanization with sulfur. It is generally known that the photoconductor is less contaminated than the sex rubber material (Patent Document 2). However, the volume resistivity is higher than that of the semi-conductive rubber material crosslinked with sulfur.

The applicant is studying a formulation using a copper compound in a study on a semi-conductive rubber material crosslinked with an organic peroxide (Patent Document 3).

Japanese Patent No. 3489384 Japanese Unexamined Patent Publication No. 6-208289 International Publication No. 2013/05/1689

However, in the study conducted by the applicant using organic peroxides and copper compounds, the volume resistivity of the semi-conductive rubber material is low and the volume resistivity environment is high due to the excessive blending of the filler. There is a problem that the effect of combining the organic peroxide and the copper compound described in Patent Document 3 for reducing the dependence is lowered, and a solution thereof has been sought.

The present invention has been made against the background of such circumstances, and in a semi-conductive rubber material using a composition containing a combination of an organic peroxide, a copper compound, and a filler, the volume resistivity is reduced and the volume resistivity is reduced. It is an object of the present invention to provide a semi-conductive rubber composition and a semi-conductive rubber material using the semi-conductive rubber composition, which can maintain the effect of reducing the environment-dependentness of volume resistivity. ..

The present inventors contain (a) a polyether polymer, (b) a copper compound, (c) an organic peroxide, and (d) a filler as a rubber component, and (b) a blending amount of the copper compound. The present invention has been completed by finding that the above-mentioned problems can be solved by a semi-conductive rubber composition obtained by examining the above and a semi-conductive rubber material made by using the semi-conductive rubber composition.

That is, the present invention relates to the following.
Item 1 (a) Contains a polyether polymer, (b) a copper compound, (c) an organic peroxide, and (d) a filler as a rubber component.
A semi-conductive rubber composition comprising (b) 0.2 parts by mass or more of a copper compound and (d) 15 to 80 parts by mass of a filler with respect to 100 parts by mass of the rubber component (a). ..
Item 2 The semi-conductive property according to Item 1, wherein the polyether-based polymer contains at least two units selected from ethylene oxide, propylene oxide, epichlorohydrin, and allyl glycidyl ether as a constituent unit. Rubber composition.
Item 3 The copper compound (b) is selected from an inorganic copper compound selected from copper oxide, copper hydroxide, copper carbonate, copper chloride, copper sulfide, and copper sulfate, a copper salt of carboxylic acid, and a copper salt of dithiocarbamic acid. Item 3. The semi-conductive rubber composition according to Item 1 or 2, wherein the semi-conductive rubber composition is at least one kind.
Item 4
Item 3. The semi-conductive rubber according to any one of Items 1 to 3, wherein the copper compound (b) contains at least one copper compound selected from copper oxide, copper stearate, and copper dimethyldithiocarbamate. Composition.
Item 5. The semi-conductive rubber composition according to any one of Items 1 to 4, further comprising (e) a cross-linking aid.
Item 6 The cross-linking aid (e) is at least one selected from trimethylolpropane trimethacrylate, triallyl isocyanate, o, o`-dibenzoyl, p-quinone dioxime, and m-phenylenedi maleimide. Item 5. The semi-conductive rubber composition according to Item 5.
Item 7. The item according to any one of Items 1 to 6, wherein the blending amount of the (b) copper compound is 0.2 to 20 parts by mass with respect to 100 parts by mass of the rubber component (a). Semi-conductive rubber composition.
Item 8 When the content of the (c) organic peroxide with respect to 100 parts by mass of the (a) rubber component is X parts by mass and the amount of active oxygen of the (c) organic peroxide is Y (%).
0.4 ≤ X x Y ≤ 200
Item 2. The semi-conductive rubber composition according to any one of Items 1 to 7.
Item 9. The semi-conductive rubber composition according to any one of Items 1 to 8, further comprising (f) a conductive agent.
Item 10 The filler (d) is selected from calcium carbonate, talc, silica, clay, carbon fiber, glass fiber, carbon black, titanium oxide, magnesium oxide, hydrotalcite, magnesium hydroxide, antimony oxide, and zinc oxide. Item 2. The semi-conductive rubber composition according to any one of Items 1 to 9, wherein the semi-conductive rubber composition is at least one kind.
Item 11 A semi-conductive rubber material using the semi-conductive rubber composition according to any one of Items 1 to 10.
Item 12 A semi-conductive rubber roll or a semi-conductive endless rubber belt using the semi-conductive rubber material according to Item 11.
Item 13 An electrophotographic apparatus using the semi-conductive rubber roll or semi-conductive endless rubber belt according to Item 12.

The semi-conductive rubber material obtained by the semi-conductive rubber composition of the present invention has low contamination because it uses an organic peroxide as a cross-linking agent. Therefore, such a semi-conductive rubber material is very useful for semi-conductive rubber rolls and belts of copiers, printers and the like.

In Patent Document 3, when the (d) filler is excessively contained in the semi-conductive rubber composition of the present invention, the volume resistivity of the semi-conductive rubber material is lowered and the environment dependence of the volume resistivity is reduced. The effect of combining the described organic peroxide and copper compound is reduced, but (b) the blending amount of the copper compound should be 0.2 parts by mass or more with respect to 100 parts by mass of the rubber component (a). Therefore, a good effect can be maintained.

Hereinafter, the present invention will be described in detail.

The semi-conductive rubber composition of the present invention is characterized by containing (a) a polyether polymer, (b) a copper compound, (c) an organic peroxide, and (d) a filler as a rubber component. It is a semi-conductive rubber composition.

Examples of the polyether-based polymer (rubber) used in the present invention include alkylene oxides such as ethylene oxide, propylene oxide, and n-butylene oxide, methyl glycidyl ether, ethyl glycidyl ether, n-glycidyl ether, and allyl glycidyl ether. , A homopolymer or copolymer of a compound selected from glycidyls such as phenylglycidyl ether, epihalohydrins such as epichlorohydrin and epibromhydrin, styrene oxide and the like, and these homopolymers or copolymers. The coalescence can be used alone or in combination of two or more.

The polyether polymer preferably contains two units selected from epichlorohydrin, propylene oxide, ethylene oxide, and allyl glycidyl ether as a constituent unit, and the unit of ethylene oxide and allyl glycidyl ether is used as a constituent unit. It is more preferable to include a unit of epichlorohydrin, ethylene oxide and allylglycidyl ether as a constituent unit.

As the polyether-based polymer, the composition unit based on ethylene oxide is preferably 50 to 85 mol%, more preferably 58 to 80 mol%, and 65 to 75 mol% with respect to the total polymerization units. Is particularly preferable.
As the polyether-based polymer, the structural unit based on allyl glycidyl ether is preferably 1 to 15 mol%, more preferably 2 to 12 mol%, and 3 to 10 mol% with respect to the total polymerization units. % Is particularly preferable.
As the polyether-based polymer, the constitutional unit based on epichlorohydrin is preferably 10 to 45 mol%, more preferably 15 to 35 mol%, and 20 to 30 mol% with respect to the total polymerization units. It is particularly preferably mol%.

The semi-conductive rubber composition of the present invention preferably contains 10% by mass or more of the polyether polymer, and 30% by mass or more, when the total amount of the rubber component (a) is 100 parts by mass. Is more preferable, 70% by mass or more is particularly preferable, and 90% by mass or more is most preferable.

Specific examples of the polyether polymer of the present invention include epichlorohydrin homopolymer, epichlorohydrin-ethylene oxide copolymer, epichlorohydrin-propylene oxide copolymer, and epichlorohydrin-. Ethyleneoxide-allyl glycidyl ether ternary copolymer, epichlorohydrin-propylene oxide-allyl glycidyl ether ternary copolymer, ethylene oxide-propylene oxide-allyl glycidyl ether ternary copolymer, epichlorohydrin-ethylene It is an oxide-propylene oxide-allyl glycidyl ether quaternary copolymer or the like, and may be composed by blending a plurality of polymers. The molecular weight of the polyether polymer is not particularly limited, but _{it may be any molecular weight such that ML 1 + 4} (100 ° C.) = 20 to 150 in the Mooney viscosity display.

The polyether-based polymer can be produced by a solution polymerization method, a slurry polymerization method or the like in a temperature range of 20 to 100 ° C. using a catalyst capable of ring-opening polymerization of an oxylane compound. Examples of such a catalyst include a catalyst system in which organic aluminum is mainly used and reacted with an oxo acid compound of water or phosphorus, acetylacetone, etc., a catalyst system in which organic zinc is mainly used and water is reacted with the catalyst system, and organic tin-. Examples thereof include a phosphoric acid ester condensate catalyst system. For example, the polyether-based polymer of the present invention can be produced using the organotin-phosphate ester condensate catalyst system described in US Pat. No. 3,773,694 by the applicant. When copolymerizing by such a production method, it is preferable to copolymerize these components substantially randomly.

In the semi-conductive rubber composition of the present invention, as the rubber component (a), only the polyether-based polymer may be contained, or a rubber type other than the polyether-based polymer may be further contained. Examples of rubber other than the polyether polymer obtained by polymerizing an oxylan compound include natural rubber and synthetic rubber, and examples of synthetic rubber include isoprene rubber (IR), 1,2-polybutadiene (VBR), and styrene butadiene rubber. (SBR), Butyl Rubber (IIR), Ethylene Propropylene Rubber (EPM), Ethylene Propropylene Diene Rubber (EPDM), Chloroprene Rubber (CR), Chlorosulfonated Polyethylene (CSM), Chlorinated Polyethylene (CPE), Acrylic Rubber (ACM) , Acrylonitrile butadiene rubber (NBR), hydride acrylonitrile butadiene rubber (H-NBR), and be at least one selected from ethylene propylene rubber (EPDM), chloroprene rubber (CR), and acrylonitrile butadiene rubber (NBR). Is preferable.

When the rubber component of the semi-conductive rubber composition of the present invention contains a rubber type other than the polyether polymer, the polyether polymer is 10 to 90% by mass in the rubber component, and the poly It preferably contains 90 to 10% by mass of a rubber type other than the ether-based polymer, 30 to 90% by mass of the polyether polymer, and 70 to 10% by mass of a rubber type other than the polyether polymer. More preferably, it contains 70 to 90% by mass of the polyether polymer, and particularly preferably 30 to 10% by mass of a rubber type other than the polyether polymer.

The copper compound (b) in the present invention can be used without limitation of the inorganic copper compound and the organic copper compound, and specific examples thereof include copper thiocyanate (rodane copper) and copper cyanide as the inorganic copper compound. (Copper Bronze), Soda Copper Bronze, Potassium Bronze, Copper Sulfate, Copper Nitrate, Copper Carbonate, Copper Iodine, Copper Acetate Hydrate, Copper Pyrophosphate, Copper Borofide, Copper Oxide, Copper Hydroxide, Examples include copper peroxide, copper chloride, copper iodide, copper bromide, copper fluoride, copper carbide, copper sulfide, ammonium cupric chloride, copper azide, etc. Examples of organic copper compounds are copper acetate and copper octylate. Copper salts of carboxylic acids such as copper naphthenate, copper stearate, copper benzoate, copper laurate, copper terephthalate, copper dimethyldithiocarbamate, copper diethylcarbamate, copper dibutyldithiocarbamate, N-ethyl-N-phenyl Examples thereof include copper salts of dithiocarbamic acid such as copper dithiocarbamate, copper N-pentamethylene dithiocarbamate, copper dibenzyl dithiocarbamate, and phthalocyanine copper (phthalocyanine blue, phthalocyanine green). The copper compound (b) of the present invention is an inorganic copper compound selected from copper oxide, copper hydroxide, copper carbonate, copper chloride, copper sulfide, and copper sulfate, a copper salt of carboxylic acid, and a copper salt of dithiocarbamic acid. It is preferably copper oxide, copper stearate, or copper dimethyldithiocarbamate.

The lower limit of the amount of the (b) copper compound to be blended is 0.2 parts by mass or more, preferably 0.25 parts by mass or more, preferably 0.3 parts by mass with respect to 100 parts by mass of the rubber component (a). It is preferably parts or more, the upper limit is preferably 20 parts by mass or less, more preferably 15 parts by mass or less, and particularly preferably 10 parts by mass or less.

In Patent Document 3, when the (d) filler is excessively contained in the semi-conductive rubber composition of the present invention, the volume resistivity of the semi-conductive rubber material is lowered and the environment dependence of the volume resistivity is reduced. The effect of combining the described organic peroxide and copper compound is reduced, but (b) the blending amount of the copper compound should be 0.2 parts by mass or more with respect to 100 parts by mass of the rubber component (a). Therefore, a good effect can be maintained.

Specific examples of the (c) organic peroxide used for cross-linking the semi-conductive rubber composition in the present invention include tert-butylhydroperoxide and 1,1,3,3-tetramethylbutylhydroperoxide. , Cumenhydroperoxide, diisopropylbenzenehydroperoxide, di-tert-butyl peroxide, dicumyl peroxide, tert-butylcumyl peroxide, 1,1-tert-butylperoxycyclohexane, 2,5-dimethyl-2 , 5-Ditert-butylperoxyhexane, 2,5-dimethyl-2,5-ditertdibutylperoxyhexin-3, 1,3-bistert-butylperoxyisopropylbenzene, 2,5-dimethyl- 2,5-Dibenzoyl peroxyhexane, 1,1-bistert-butylperoxy-3,3,5-trimethylcyclohexane, n-butyl-4,4-bistert-butylperoxyvalerate, benzoyl peroxide , Tert-Butyl peroxide isobutyrate, tert-butyl peroxy2-ethylhexanoate, tert-butyl peroxybenzoate, tert-butyl peroxyisopropylcarbonate, tert-butylperoxyallyl monocarbonate, p- Methylbenzoyl peroxide is mentioned and preferably contains at least one. Further, (a) it can be used in combination with a known cross-linking agent used when cross-linking a rubber component containing a polyether polymer.

The blending amount of the (c) organic peroxide is such that the content of the (c) organic peroxide is X parts by mass with respect to 100 parts by mass of the (a) rubber component, and the active oxygen of the (c) organic peroxide is used. When the amount is Y (%)
0.4 ≤ X x Y ≤ 200
Is preferable
0.4 ≤ X x Y ≤ 100
Is more preferable
It is particularly preferable that 0.4 ≦ X × Y ≦ 80.
For X × Y, it may be 0.6 or more, 1 or more, 60 or less, 40 or less, and 30 or less.
(C) The amount of active oxygen Y (%) of the organic peroxide can be calculated from the theoretical amount of active oxygen (%) of the compound and the purity (%) of the compound used. The theoretical amount of active oxygen is calculated by the following formula (1).
Theoretical active oxygen amount (%) = {(number of peroxide bonds in the molecule x 16) / molecular weight} x 100

The semi-conductive rubber composition of the present invention contains (d) a filler. Examples of the filler (d) in the present invention include organic fillers and inorganic fillers, preferably inorganic fillers, and oxides and hydroxides of metals such as titanium, magnesium, zinc, and calcium. , Carbonate. Specifically, calcium carbonate, talcite, silica, clay, carbon fiber, glass fiber, carbon black, titanium oxide, magnesium oxide, hydrotalcite, magnesium hydroxide, antimony oxide, zinc oxide and the like can be exemplified.

The lower limit of the content of the filler (d) may be 15 parts by mass or more, 20 parts by mass or more, and 25 parts by mass or more with respect to 100 parts by mass of the rubber component (a). The upper limit may be 80 parts by mass or less, 60 parts by mass or less, and 50 parts by mass or less.

In the semi-conductive rubber composition of the present invention, (e) a cross-linking aid may be further contained in addition to the above-mentioned components (a), (b), (c) and (d). Specific examples of the (e) cross-linking aid include sulfur, sulfur compounds such as dipentamethylene thiuram tetrasulfide, ethylene di (meth) acrylate, polyethylene di (meth) acrylate, divinylbenzene, diallyl phthalate, triallyl cyanurate, and tri. Polyfunctional monomers such as allyl isocyanurate, trimethyl propantrimethacrylate, m-phenylenedi maleimide, toluylene bismaleimide, p-quinone oxime, p, p'-benzoyl quinone oxime, o, o'- Examples thereof include oxime compounds such as dibenzoyl-p-quinone dioxime.
The (e) cross-linking aid of the present invention is at least one selected from trimethylolpropane trimethacrylate, triallyl isocyanurate, o, o`-dibenzoyl-p-quinonedioxime, and m-phenylenedimaleimide. Is preferable.

The lower limit of the blending amount of the (e) cross-linking aid is preferably 0.01 part by mass or more, and more preferably 0.05 part by mass or more with respect to 100 parts by mass of the rubber component (a). , 0.1 part by mass or more, more preferably 0.2 part by mass or more, particularly preferably 0.3 part by mass or more, and the upper limit is 10 parts by mass or less. Is preferable, and it is more preferably 5 parts by mass or less, and particularly preferably 3 parts by mass or less.

In the semi-conductive rubber composition of the present invention, (f) a conductive agent may be further added in addition to the above-mentioned components (a), (b), (c) and (d). Examples of the (f) conductive agent in the present invention include quaternary ammonium salts, borates, perchlorates, potassium salts, surfactants, lithium salts and the like. Specifically, tetrabutylammonium bromide, tetrabutylammonium percolate, ethyltributylammonium etosulfate, sodium perchlorate, lithium perchlorate, calcium perchlorate, lauryltrimethylammonium chloride, stearyltrimethylammonium chloride, octadecyl. Examples thereof include trimethylammonium chloride, dodecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, trioctylpropylammonium bromide, dimethylalkyllauryl betaine, lithium trifluoromethanesulfonate, and the like, and it is preferable to include at least one of them.

The content of the conductive agent (f) is preferably 0.1 to 10 parts by mass, more preferably 0.2 to 8 parts by mass with respect to 100 parts by mass of the rubber component (a). , 0.3 to 5 parts by mass is particularly preferable.

As the anti-aging agent used in the present invention, known anti-aging agents can be used, and examples thereof include phenyl-α-naphthylamine, p-toluenesulfonylamide-diphenylamine, 4,4-α, α-dimethylbenzyldiphenylamine. , High temperature reaction product of diphenylamine and acetone, low temperature reaction product of diphenylamine and acetone, low temperature reaction product of diphenylamine, aniline, acetone, reaction product of diphenylamine and diisobutyllene, octylated diphenylamine, substituted diphenylamine, alkylated diphenylamine, diphenylamine Derivatives, N, N'-diphenyl-p-phenylenediamine, N-isopropyl-N'-phenyl-p-phenylenediamine, N, N'-di-2-naphthyl-p-phenylenediamine, N-phenyl-N' -3-methacryloyloxy-2-hydroxypropyl-p-phenylenediamine, N, N'-bis 1-methylheptyl-p-phenylenediamine, N, N'-bis 1,4-dimethylpentyl-p-phenylenediamine, A mixture of N-1,3-dimethylbutyl-N'-phenyl-p-phenylenediamine, diallyl-p-phenylenediamine, phenyl, octyl-p-phenylenediamine, phenyl-α-naphthylamine and diphenyl-p-phenylenediamine. , A polymer of 2,2,4-trimethyl-1,2 dihydroquinoline, 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline, 2,5-di-tert-amylhydroquinone. , 2,5-Di-tert-butylhydroquinone, 1-oxy-3-methyl-4-isopropylbenzene, 2,6-di-tert-butyl-4-ethylphenol, butylhydroxyanisole, 2,6-di- tert-butyl-α-dimethylamino-p-cresol, mixture of 2,6-di-tert-butylphenol, 2,4,6-tri-tert-butylphenol and ortho-tert-butylphenol, styrenated phenol, alkylated phenol , A mixture of alkyl and aralkyl substituted phenols, phenol derivatives, 2,2'-methylene-bis-4-methyl-6-tert-butylphenol, 2,2'-methylene-bis-4-methyl-6-cyclohexylphenol, 2,2'-Methyl-bis-4-ethyl-6-tert-butylphenol, 4,4-methylene-bis-2,6-di-tert-butylfe Nord, methylene crosslinked polyvalent alkylphenol, alkylated bisphenol, butylization reaction product of p-cresol and dicyclopentadiene, mixture of polybutylated bisphenol A, 4,4-thiobis-6-tert-butyl-3-methylphenol , 4,4-Butylidenebis-3-methyl-6-tert-butylphenol, 4,4'thiobis (3-methyl-6-tert-butylphenol), 2,4-bisoctylthiomethyl-O-cresol, hinderedphenol , Hindertobisphenol, 2-mercaptobenzimidazole, 2-mercaptomethylbenzimidazole, 2-mercaptobenzimidazole zinc salt, 2-mercaptomethylbenzimidazole zinc salt, 4 and 5-mercaptomethylbenzimidazole, 4 and 5 -Zinc salt of mercaptomethylbenzimidazole, dioctadecyldisulfide, nickel diethyldithiocarbamate, nickel dibutyldithiocarbamate, 1,3-bisdimethylaminopropyl-2-thiourea, tributylthiourea, bis2-methyl-4-3- n-alkylthiopropionyloxy-5-tert-butylphenyl sulfide, bis 3,5-di-tert-butyl-4-hydroxybenzyl sulfide, mixed lauryl steathiodipropionate, cyclic acetal, 60% polymer polyol and hydrogenated silica 40% mixture, special polyethylene glycol processed product with bimolecular structure of polyethylene and polyethylene glycol, specially designed mixture of inert filler and polymer polyol, composite anti-aging agent, enol ether, 1,2,3-benzotriazole , 3-N-salicyloylamino-1,2,4-triazol, triazine derivative complex, decamethylene dicarboxylic acid disalicyloyl hydrazide, N, N'-bis 3-3,5-di-tert- Examples thereof include 4-hydroxyphenylpropionylhydrazine, tetrakis-methylene-3-3', 5'-di-tert-butyl 4'hydroxyphenylpropionatemethane and the like.

For the semi-conductive rubber composition of the present invention, various acid receiving agents, reinforcing agents, plasticizers, processing aids, difficulties, etc., which are used in the technical fields in addition to the above, as long as the effects of the present invention are not impaired. A flame retardant, a pigment, a vulcanization accelerator and the like can be optionally blended. Further, it is also possible to blend rubber, resin and the like, which are usually performed in the art, as long as the characteristics of the present invention are not lost.

As a method for blending the semi-conductive rubber composition of the present invention, any means conventionally used in the field of polymer processing can be used, and for example, a mixing roll, a Banbury mixer, various kneaders and the like can be used. .. Examples of the molding method include compression molding, extrusion molding, and injection molding using a mold, but extrusion molding and injection molding using the semi-conductive rubber composition of the present invention are preferable.

The rubber material using the semi-conductive rubber composition of the present invention is not particularly limited in the production method, but is preferably obtained by cross-linking. Specifically, it is usually obtained by heating to 100 to 200 ° C., and the cross-linking time varies depending on the temperature, but is usually performed between 0.5 and 300 minutes. As the method of cross-linking molding, any method such as compression molding by a mold, injection molding, air bath, heating by infrared rays or microwaves can be used.

Hereinafter, a specific description will be given with reference to Examples and Comparative Examples. The present invention is not limited to this.

First, each compounding agent shown in Table 1 was kneaded with a pressurized kneader at 120 ° C. to prepare an A kneading compound. This A kneading compound was kneaded with an open roll to prepare a B kneading compound. In the table, A is a raw material for the A kneading compound, and B is a raw material to be blended with the A kneading compound when the B kneading compound is prepared.

The compounding agents used in the implementation and comparative examples are shown below.
* 1 Epichlorohydrin-ethylene oxide-allyl glycidyl ether ternary copolymer "EPION-301" manufactured by Osaka Soda Co., Ltd.
* 2 "Plastrogin J" manufactured by Fuso Chemical Industry Co., Ltd.
* 3 "Nocrack 300" manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.
* 4 Light calcium carbonate "Silver W" manufactured by Shiraishi Calcium Co., Ltd.
* 5 "Park Mill D-40 (40% dicumyl peroxide product, amount of active oxygen 2.37)" manufactured by NOF CORPORATION
* 6 "Barnock PM" manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.

<Volume resistivity>
The sheet of the B kneading compound prepared above was press vulcanized at 160 ° C. for 15 minutes. After adjusting the state of the obtained crosslinked sheet under 10 ° C./15% RH environment, 23 ° C./50% RH environment, and 35 ° C./85% RH environment, respectively, it conforms to JIS K6271 and is double-layered. Using a high rester manufactured by Mitsubishi Yuka Co., Ltd. using a ring electrode, apply 10 V and measure the volume resistivity after 1 minute.

<Environmental change in volume resistivity>
The environmental variation of the volume resistivity was determined based on the respective volume resistivity under the 10 ° C./15% RH environment and the 35 ° C./85% RH environment obtained by the measurement of the volume resistivity. The smaller the value of the environmental variation of the volume resistivity, the smaller the environmental dependence of the volume resistivity. The environmental resistivity of the volume resistivity of the present application is the logarithm of the volume resistivity under a low temperature and low humidity environment (10 ° C./15% RH environment) and the volume resistivity under a high temperature and high humidity environment (35 ° C./85% RH environment). It is calculated from the difference in the logarithm of the rate, and more specifically, it is calculated by the following formula.
log ₁₀ (10 ° C x 15% RH volume resistivity) -log ₁₀ (35 ° C x 85% RH volume resistivity)

<Repulsive modulus>
The rebound resilience was measured by a pendulum test method according to JIS K6255 with a measuring device "Desktop Repulsion Tester manufactured by Polymer Meter Co., Ltd." RT-90.

Table 2 shows the test results of Examples and Comparative Examples obtained from each test method.

As shown in Table 2, in Examples 1 to 6, (a) the filler was excessive by adding 0.2 parts by mass or more of the copper compound to 100 parts by mass of the rubber component. It is possible to have a good environmental resistivity of volume resistivity even when it is blended with.

The semi-conductive rubber composition which is the subject of the present invention has excellent environmental resistivity in volume resistivity while maintaining semi-conductivity, and can be used as a developing, charging, or transfer roll in a laser printer or a copier. It can be widely applied.

Claims (13)

As a rubber component, (a) a polyether polymer, (b) a copper compound, (c) an organic peroxide, and (d) a filler are contained.
A semi-conductive rubber composition comprising (b) 0.2 parts by mass or more of a copper compound and (d) 15 to 80 parts by mass of a filler with respect to 100 parts by mass of the rubber component (a). .. The semi-conductive rubber according to claim 1, wherein the polyether-based polymer contains at least two units selected from ethylene oxide, propylene oxide, epichlorohydrin, and allyl glycidyl ether as a constituent unit. Composition. The copper compound (b) is at least selected from an inorganic copper compound selected from copper oxide, copper hydroxide, copper carbonate, copper chloride, copper sulfide, and copper sulfate, a copper salt of carboxylic acid, and a copper salt of dithiocarbamic acid. The semi-conductive rubber composition according to claim 1 or 2, characterized in that it is a kind. The semi-conductive according to any one of claims 1 to 3, wherein the copper compound (b) contains at least one copper compound selected from copper oxide, copper stearate, and copper dimethyldithiocarbamate. Rubber composition. The semi-conductive rubber composition according to any one of claims 1 to 4, further comprising (e) a cross-linking aid. The cross-linking aid (e) is at least one selected from trimethylolpropane trimethacrylate, triallyl isocyanate, o, o`-dibenzoyl, p-quinone dioxime, and m-phenylenedi maleimide. The semi-conductive rubber composition according to claim 5. The half according to any one of claims 1 to 6, wherein the blending amount of the (b) copper compound is 0.2 to 20 parts by mass with respect to 100 parts by mass of the rubber component (a). Conductive rubber composition. When the content of the (c) organic peroxide with respect to 100 parts by mass of the (a) rubber component is X parts by mass and the amount of active oxygen of the (c) organic peroxide is Y (%).
0.4 ≤ X x Y ≤ 200
The semi-conductive rubber composition according to any one of claims 1 to 7. The semi-conductive rubber composition according to any one of claims 1 to 8, further comprising (f) a conductive agent. The filler (d) is selected from at least calcium carbonate, talc, silica, clay, carbon fiber, glass fiber, carbon black, titanium oxide, magnesium oxide, hydrotalcite, magnesium hydroxide, antimony oxide, and zinc oxide. The semi-conductive rubber composition according to any one of claims 1 to 9, wherein the semi-conductive rubber composition is one kind. A semi-conductive rubber material using the semi-conductive rubber composition according to any one of claims 1 to 10. A semi-conductive rubber roll or a semi-conductive endless rubber belt using the semi-conductive rubber material according to claim 11. An electrophotographic apparatus using the semi-conductive rubber roll or semi-conductive endless rubber belt according to claim 12.