CN104341633A

CN104341633A - Conductive rubber composite, transfer printing roller and image formation device

Info

Publication number: CN104341633A
Application number: CN201410359642.0A
Authority: CN
Inventors: 里吉直之
Original assignee: Sumitomo Rubber Industries Ltd
Current assignee: Sumitomo Rubber Industries Ltd
Priority date: 2013-08-08
Filing date: 2014-07-25
Publication date: 2015-02-11
Anticipated expiration: 2034-07-25
Also published as: CN104341633B; JP2015034878A; JP6164974B2

Abstract

The invention provides a conductive rubber composite, the conductive rubber composite can form a porous structure which satisfies demands of low cost, light weight and the like and is excellent in flexibility, and the conductive rubber composite is suitable for a transfer printing roller which is used for forming color images and is small in foaming hole diameter. The invention also provides a transfer printing roller composed of the conductive rubber composite and an image formation device provided with the transfer printing roller. The conductive rubber composite is formed in a way that in a rubber component containing SBR, EPDM and epichlorohydrin rubber, 4-12 parts by mass of a foaming agent in total 100 parts by mass of the rubber component and 70-150% by mass of blowing promoter relative to the foaming agent are mixed with cross-linking components. The transfer printing roller 1 is formed in a way that the above conductive rubber composite is subjected to extrusion forming to be cylindrical, then is pressurized in a vulcanizing boiler through pressurized water vapor, then is heated to carry out foaming and cross-linking processes. The image formation device is provided with the transfer printing roller.

Description

Conductive rubber composition, transfer roll and image processing system

Technical field

The present invention relates to a kind of conductive rubber composition, the transfer roll be made up of this conductive rubber composition and the image processing system of this transfer roll has been installed.

Background technology

Such as, utilize in the image processing system of Xxerography at laser printer, xerographic printer, plain paper facsimile or these compounding machine etc., roughly through following operation, at the image forming surface of the paper using such as stationery, plastics film.

First, the surface with the photoreceptor of photoconductivity being exposed under same electriferous state, forming the electrostatic latent image (charged operation → exposure process) corresponding with forming image on this surface.

Then, first make small colored particles toning agent under the state that the current potential of regulation is charged, with the surface contact of photoreceptor.So make toning agent according to the surperficial selective adsorption of the current potential pattern of electrostatic latent image at photoreceptor, electrostatic latent image is with toner image development (developing procedure).

Then, toner image is transferred to the surface (transfer printing process) of paper using, further by making its fixing (fixing operation), at the image forming surface of this paper using.

In this external transfer printing process, except the direct transfer printing of the toner image will formed on the surface of photoreceptor (direct transfer printing) is to the situation on the surface of paper using, also there is the situation of the surface transfer printing again (secondary transfer printing operation) in the backward paper using of the interim transfer printing in the surface of image-carrier (primary transfer operation).

In order to by the toner image direct surface from the surface transfer of photoreceptor to paper using or the surface from the surface transfer of photoreceptor to image-carrier primary transfer operation or in order to the surface from the surface transfer of image-carrier to paper using secondary transfer printing operation in transfer printing process, use the transfer roll with the roller resistance value of regulation be made up of conductive rubber composition.

Such as during direct transfer printing, in transfer printing process, mutual with under the state applying the transfer voltage specified between the photoreceptor of the crimp force of regulation crimping and transfer roll, between paper using led to paper, make the toner image formed on the surface of photoreceptor be transferred to the surface of paper using.

Recently, as particularly at middle transfer rolls used such as the conventional laser printers towards developing country, have and require the trend of following transfer roll: use conventional material, as far as possible structure simple as far as possible and can manufacture inexpensively.

In order to meet these requirements, commonly use the transfer roll with vesicular structure as transfer roll.By being set to vesicular structure, can reducing and form material suppression materials cost, and its lightweight can be cut down transport charge etc.In addition, even if omit the cooperation of softening agent or reduce mixing ratio, the flexibility of transfer roll appropriateness can also be given by vesicular structure.

The transfer roll of above-mentioned vesicular structure, usually such as uses the conductive rubber composition with electroconductibility, bridging property and foaminess, manufactures according to following order.

That is, by conductive rubber composition by the shower nozzle of extrusion machine continuously extrusion molding be tubular, be then cut into the length of regulation, pressurizeed by compressed steam in vulcanizing boiler, heating and carry out foaming and being cross-linked.

Then, using the heating such as baking box, make foaming, crosslinked cylindrical body secondary crosslinking, by being ground to the external diameter of regulation after cooling, manufacturing transfer roll.

As the rubber components of composition conductive rubber composition, the production cost of transfer roll is compressed further from the view point of reducing material cost, such as preferably be not used alone the ionic conductivity rubber of the high prices such as epichloro hydrin rubber, but by this ionic conductivity rubber and bridging property rubber blending.

As above-mentioned bridging property rubber, acrylonitrile butadiene rubber (NBR) is common.But, the production cost of transfer roll is further compressed in order to meet above-mentioned requirements, as bridging property rubber, replace NBR, preferably by styrene butadiene ribber (SBR) and ethylene propylene diene rubber (EPDM) and with (reference patent documentation 1 etc.).

In the paralled system of these 2 kinds of bridging property rubber and ionic conductivity rubber, while the good ozone resistance of transfer roll can be maintained, suppress material cost further.

Namely, for the ionic conductivity rubber giving the necessary high price of roller resistance value that transfer roll specifies, by with bridging property rubber and with reducing its mixing ratio, and more high cost is cheap, therefore, it is possible to reduce material cost further because SBR and NBR in bridging property rubber compares versatility.

But because SBR is to the patience of the ozone that the inside of laser printer etc. occurs, namely ozone resistance is insufficient, therefore and use EPDM.

Due to EPDM, not only himself ozone resistance is excellent, and it also has the effect of the ozone deterioration suppressing SBR, therefore, it is possible to improve the ozone patience of transfer roll.

As foaming ingredient, will the whipping agent of gas be produced by thermal degradation and there is the decomposition temperature that reduces this whipping agent and have that to promote that the frothing aid of effect decomposed carries out combining be common.

Particularly Cellmic C 121 (whipping agent, H ₂nOCN=NCONH ₂, be also abbreviated as below " ADCA ") and the combination of Urea Series frothing aid be extensively used (with reference to patent documentation 1 etc.).

Prior art document

Patent documentation

Patent documentation 1 Japanese Unexamined Patent Publication 2012-108376 publication

Summary of the invention

As such as by overlapping for the image of cyan, magenta and the multiple color toning agent such as yellow and form coloured image, the transfer roll that uses in the image processing system (colored machine) of reply coloured image, use the transfer roll that the periphery of non-porous structure is level and smooth always.

This is because use transfer roll transfer printing repeatedly to each each colour toners, therefore in order to prevent the confusion of the coloured image formed and improve image quality, the periphery of preferred transfer roll is level and smooth and charged characteristic is uniform.

But, for colored machine transfer roll, to cut down for the purpose of cost, lightweight etc., seeking to adopt vesicular structure.In this case, require to try one's best in the foam bubble footpath of the foam bubble exposed at periphery little, specifically usually require to be less than 300 μm.

But, the transfer roll of the existing vesicular structure such as, recorded in patent documentation 1, because the foam bubble footpath of the foam bubble exposed at periphery is larger than above-mentioned scope, although can be no problem in the monochrome images such as monochrome image are formed use, be not suitable for the formation of coloured image.

The object of the present invention is to provide a kind of conductive rubber composition, while it can be formed and meet the requirement such as cost cutting, lightweight, there is the vesicular structure of flexibility excellence, and the transfer roll that the foam bubble footpath being applicable to coloured image formation is little.In addition the object of the present invention is to provide the transfer roll be made up of above-mentioned conductive rubber composition and the image processing system having installed this transfer roll.

The present invention is that be characterised in that can by compressed steam pressurization, heating and carry out the conductive rubber composition that foams and be cross-linked in vulcanizing boiler, it contains: at least containing the rubber components of styrene butadiene ribber, ethylene propylene diene rubber and epichloro hydrin rubber, for the foaming ingredient that described rubber components foams by the crosslinking component that is cross-linked by described rubber components and being used for; Further, the frothing aid that the described whipping agent of promotion producing the whipping agent of gas and 70 % by weight ~ 150 % by weight of described foaming dosage by thermal degradation that it is 4 mass parts ~ 12 mass parts that described foaming ingredient contains relative to total amount 100 mass parts of described rubber components decomposes.

In addition, the invention is characterized in the transfer roll be made up of the conducting rubber of the invention described above.

The invention is characterized in it is the image processing system of the transfer roll having installed the invention described above further.

According to the present invention, as foaming ingredient, coordinate with the ratio of more than 70 % by weight of the dosage that foams together with produced the whipping agent of gas by thermal degradation and there is the decomposition temperature reducing this whipping agent, the frothing aid promoting Decomposition, thus the foam bubble footpath of the foam bubble exposed at transfer roll periphery can be made to control in the scope being less than 300 μm of above-mentioned explanation.

Namely coordinate during frothing aid and reduce due to the decomposition temperature of whipping agent, this whipping agent from the very short time that heating starts, cylindrical body roughly on the whole substantially while and decompose equably, foam.And then because foam bubble adjacent while foaming prolonged expansion is because of the mutual repression of swelling of mutual bulging force, result causes the abscess footpath of each foam bubble to diminish.

Meet while cost cutting, lightweight etc. require therefore, it is possible to formed, there is the vesicular structure of flexibility excellence, and be applicable to the little transfer roll in foam bubble footpath that coloured image formed.

Should illustrate in the present invention, the mixing ratio of whipping agent to be defined as relative to total amount 100 mass parts of rubber components be 4 mass parts ~ 12 mass parts is based on following reason.

Namely, the mixing ratio of whipping agent is when being less than this scope, and the distance between the whipping agent in conductive rubber composition becomes large, can not obtain the effect of the mutual repression of swelling of adjacent foam bubble originating from each whipping agent.Therefore, foam bubble footpath becomes large on the whole, can not obtain being applicable to the transfer roll that the foam bubble footpath of coloured image formation is little.

When foaming insufficient in addition, also there is the minimizing that can not obtain above-mentioned explanation and form material and suppress the effect of Master Cost and lightweight to cut down the problem of the effects such as trucking costs.

On the other hand, when mixing ratio overruns, although foam bubble footpath can be diminished, rubber hardness becomes really up to the mark, can not give the suitable good flexibility as this transfer roll to transfer roll.Therefore, such as produce and cannot crimp under the state guaranteeing wide pinching width photoreceptor, the transfer efficiency of toning agent reduces, to photoreceptor cause damage problem.

On the other hand, by the mixing ratio of whipping agent is arranged on above-mentioned scope, guarantee the good flexibility of transfer roll, while this foam bubble footpath can be reduced further.

In addition, in the present invention, the mixing ratio of frothing aid is defined as foaming dosage 70 % by weight ~ 150 % by weight is based on following reason.

That is, when the mixing ratio of frothing aid is less than this scope, although the good flexibility of transfer roll can be guaranteed, can not obtain because of the mechanism of above-mentioned explanation the effect reducing foam bubble footpath.Therefore, foam bubble footpath becomes large on the whole, can not obtain being applicable to the transfer roll that the foam bubble footpath of coloured image formation is little.

On the other hand, when mixing ratio overruns, although foam bubble footpath can be diminished, rubber hardness becomes really up to the mark, can not give the suitable good flexibility as this transfer roll to transfer roll.Therefore, there is the possibility producing above-mentioned various problem.

On the other hand, by the mixing ratio of frothing aid is arranged on above-mentioned scope, guarantee the good flexibility of transfer roll, while can further reduce foam bubble footpath.

NBR, chloroprene rubber (CR), divinyl rubber (BR) and acrylic rubber (ACM) isopolarity rubber is preferably coordinated further as above-mentioned rubber constituent.

Thereby, it is possible to the roller resistance value of fine setting transfer roll.In addition, uniform in foaming, can form uniform as far as possible vesicular structure.

Transfer roll of the present invention, preferably through being tubular by conductive rubber composition extrusion molding of the present invention, by compressed steam pressurization, heating and the operation carrying out foaming and being cross-linked manufactures in vulcanizing boiler.

Conductive rubber composition of the present invention, due to the frothing aid of the amount containing above-mentioned explanation, the decomposition temperature of whipping agent reduces, so by using the tank sulfuration of vulcanizing boiler to foam well, can be manufactured on to meet as described above while cost cutting, lightweight etc. require and there is the vesicular structure of flexibility excellence, and the transfer roll that the foam bubble footpath of formation being applicable to coloured image is little.

Can provide can manufacture to meet while cost cutting, lightweight etc. require according to the present invention and there is the vesicular structure of flexibility excellence, and the conductive rubber composition of the little transfer roll in the foam bubble footpath of formation being suitable for coloured image.In addition the transfer roll be made up of above-mentioned conductive rubber composition and the image processing system having installed this transfer roll can be provided according to the present invention.

Accompanying drawing explanation

Fig. 1 is the stereographic map of an example of the embodiment that transfer roll of the present invention is shown.

The explanation of symbol

1 transfer roll

2 through holes

3 rotating shafts

4 peripherys

Embodiment

Conductive rubber composition

The present invention is characterised in that in vulcanizing boiler, to carry out foam and be cross-linked conductive rubber composition by compressed steam pressurization, heating, it contains: at least containing the rubber components of styrene butadiene ribber, ethylene propylene diene rubber and epichloro hydrin rubber, for the foaming ingredient that described rubber components foams by the crosslinking component that is cross-linked by described rubber components and being used for; Further, the frothing aid that the described whipping agent of promotion producing the whipping agent of gas and 70 % by weight ~ 150 % by weight of described foaming dosage by thermal degradation that it is 4 mass parts ~ 12 mass parts that described foaming ingredient contains relative to total amount 100 mass parts of described rubber components decomposes.

SBR

As SBR, various to vinylbenzene and 1,3-butadiene emulsion polymerization method, solution polymerization process etc. polymerization is carried out copolymerization and the various SBR synthesized all can use.In addition as SBR, comprise the oil-filled type SBR adding oil-filled adjustment flexibility and the non-oil-filled type SBR do not added, these all can use.

And as SBR, the SBR being categorized as high-phenylethylene type, middle styrene type and low-styrene type according to styrene content all can use.By changing styrene content, degree of crosslinking, the various physical property of transfer roll can be adjusted.

Can use that these SBR's is one kind or two or more.

Rubber components is only containing SBR, EPDM and epichloro hydrin rubber these 3 kinds, time containing polar rubber, be more than 40 mass parts in total amount 100 mass parts of preferred this rubber components of the mixing ratio of SBR, particularly preferably more than 60 mass parts, preferably below 90 mass parts, particularly preferably below 80 mass parts.In addition time containing polar rubber, also based on the mixing ratio of this polar rubber, but be more than 30 mass parts in preferred every rubber components total amount 100 mass parts, preferably below 50 mass parts.

When mixing ratio is less than this scope, there is the possibility of the advantage of the cheap such SBR of the versatility high cost that can not make full use of above-mentioned explanation.

On the other hand, when overruning, the mixing ratio of EPDM relatively reduces, and there is the possibility can not giving the good ozone patience of transfer roll.In addition the mixing ratio of epichloro hydrin rubber also relatively reduces, and there is the possibility can not giving the good ionic conductivity of transfer roll.

Should illustrate, when using oil-filled type SBR as SBR, mixing ratio is the mixing ratio of the SBR as solid composition self contained in this oil-filled type SBR.

EPDM

As EPDM, in main chain, import the various EPDM of double bond by adding a small amount of the 3rd composition (diene composition) at ethene and propylene, all can use.As EPDM, because the kind of the 3rd composition, the difference of amount can provide various products.The 3rd composition representatively, such as, can enumerate ethylidene norbornene (ENB), Isosorbide-5-Nitrae-hexadiene (Isosorbide-5-Nitrae-HD), Dicyclopentadiene (DCPD) (DCP) etc.Usually Z-type catalyst is used as polymerizing catalyst.

Be more than 5 mass parts in preferred every rubber components total amount 100 mass parts of mixing ratio of EPDM, preferably below 40 mass parts, particularly preferably below 20 mass parts.

Mixing ratio is less than this scope, there is the possibility can not giving the good ozone patience of transfer roll.

On the other hand, when overruning, the mixing ratio of SBR also relatively reduces, and there is the possibility that can not make full use of the advantage of the cheap such SBR of versatility high cost.The mixing ratio of epichloro hydrin rubber also relatively reduces in addition, there is the possibility can not giving the good ionic conductivity of transfer roll.

Epichloro hydrin rubber

Epichlorohydrin homopolymers can be enumerated as epichloro hydrin rubber, Epicholorohydrin-ethylene oxide copolymer (ECO), Epicholorohydrin-propylene oxide copolymer, Epicholorohydrin-propenyl glycidyl ether copolymer, Epicholorohydrin-ethylene oxide-propenyl glycidyl ether terpolymer (GECO), Epicholorohydrin-propylene oxide-propenyl glycidyl ether terpolymer and Epicholorohydrin-ethylene oxide-propylene oxide-propenyl glycidyl ether tetrapolymer etc. one kind or two or more.

As the multipolymer that epichloro hydrin rubber can be containing ethylene oxide in these materials, particularly preferably ECO and/or GECO.

Ethylene oxide content all preferably more than 30 % by mole in above-mentioned two multipolymers, particularly preferably more than 50 % by mole, preferably less than 80 % by mole.

Ethylene oxide has the effect of the roller resistance value lowering transfer roll.But due to ethylene oxide content be less than this scope time, can not fully obtain above-mentioned effect, exist and fully can not reduce the possibility of the roller resistance value of transfer roll.

On the other hand, when ethylene oxide content overruns, hinder the segmental mobility of molecular chain owing to causing the crystallization of ethylene oxide, have the trend of the roller resistance value raising transfer roll on the contrary.In addition, the hardness of also depositing transfer roll after cross-linking raises, the possibility that the viscosity during heating and melting of the conductive rubber composition before crosslinked raises.

In ECO, Epicholorohydrin content is the surplus of ethylene oxide content.I.e. Epicholorohydrin content preferably more than 20 % by mole, preferably less than 70 % by mole, particularly preferably less than 50 % by mole.

In addition in GECO, propenyl Racemic glycidol ether content preferably more than 0.5 % by mole, particularly preferably more than 2 % by mole, preferably less than 10 % by mole, particularly preferably less than 5 % by mole.

Propenyl glycidyl ether is guaranteed free volume by himself as side chain and plays a role, thus the crystallization of ethene suppressing oxide compound, play the effect of the roller resistance value reducing transfer roll.When but propenyl Racemic glycidol ether content is less than above-mentioned scope, above-mentioned effect can not be obtained, there is the possibility that fully can not reduce the roller resistance value of transfer roll.

On the other hand, propenyl glycidyl ether, plays function when GECO is cross-linked as cross-linking set, therefore, when propenyl Racemic glycidol ether content overruns, the cross-linking density of GECO uprises, the segmental mobility of molecular chain can be hindered, the trend that the roller resistance value having transfer roll on the contrary raises.In addition the possibility that the tensile strength, fatigue characteristic, resistance to bend(ing) etc. that also there is transfer roll reduce.

In GECO, Epicholorohydrin content is the surplus of ethylene oxide content and propenyl Racemic glycidol ether content.I.e. Epicholorohydrin content preferably more than 10 % by mole, particularly preferably more than 19.5 % by mole, preferably less than 69.5 % by mole, particularly preferably less than 60 % by mole.

As GECO, except the multipolymer of the meaning of the narrow sense by 3 kinds of monomer copolymerizables described above, known propenyl glycidyl ether is by the modifier of Epicholorohydrin-oxidation of ethylene composition copolymer (ECO) modification, and in the present invention, above-mentioned modifier also can use as GECO.

Be more than 5 mass parts in preferred every rubber components total amount 100 mass parts of mixing ratio of epichloro hydrin rubber, particularly preferably more than 10 mass parts, preferably below 40 mass parts, particularly preferably below 30 mass parts.

When mixing ratio is less than this scope, there is the possibility can not giving the good ionic conductivity of transfer roll.

On the other hand, when overruning, the mixing ratio of SBR relatively reduces, and there is the possibility that can not make full use of the advantage of the cheap such SBR of versatility high cost.In addition the mixing ratio of EPDM also relatively reduces, and there is the possibility can not giving the good ozone patience of transfer roll.

Polar rubber

When coordinating polar rubber, the roller resistance value of transfer roll can be finely tuned as described above.In addition, foaming is not uneven, forms uniform as far as possible vesicular structure.

As polar rubber, such as, can enumerate the one kind or two or more of NBR, CR, BR, ACM.Particularly preferably NBR and/or CR.

Wherein as NBR, the low butyronitrile NBR classified according to acrylonitrile content, middle butyronitrile NBR, middle high nitrile NBR, high nitrile NBR and high butyronitrile NBR all can use.

In addition as CR, such as can use chlorobutylene emulsion polymerization is synthesized, sulphur modified version and the non-sulphur modified version of classifying according to the kind of now used molecular weight adjusting agent and classify based on crystallization rate, the slow type of this crystallization degree, the type of middle degree and the arbitrary CR of rakish CR.

The mixing ratio of polar rubber, according to the roller resistance value of the transfer roll as object, can set arbitrarily, is particularly preferably more than 5 mass parts in every rubber components total amount 100 mass parts, particularly preferably more than 20 mass parts, preferably below 40 mass parts.

When mixing ratio is less than this scope, there is the possibility of the roller resistance value that fully can not obtain the fine setting transfer roll obtained by coordinating polar rubber and the effect making uniform in foaming.

When overruning in addition, the mixing ratio of SBR relatively reduces and tails off, and there is the possibility that can not make full use of the advantage of versatility this SBR high, with low cost.In addition the mixing ratio of EPDM also relatively reduces, and there is the possibility can not giving the good ozone patience of transfer roll.And the mixing ratio of epichloro hydrin rubber also relatively reduces, there is the possibility can not giving the good ionic conductivity of transfer roll.

Foaming ingredient

Whipping agent

The various whipping agents being produced gas by thermal degradation can be used as the whipping agent in foaming ingredient, as above-mentioned whipping agent, such as can enumerate ADCA, 4,4 '-oxo two (benzol sulfohydrazide) (OBSH), N, N-dinitrosopentamethlyene tetramine (DPT) etc. one kind or two or more.Particularly preferably ADCA.

What the mixing ratio of whipping agent is defined as above-mentioned explanation is that 4 mass parts ~ 12 mass parts are based on following reason relative to total amount 100 mass parts of rubber components.

That is, when the mixing ratio of whipping agent is less than this scope, the distance between the whipping agent in conductive rubber composition becomes large, can not obtain the effect of the mutual repression of swelling of adjacent foam bubble originating from each whipping agent.Therefore, foam bubble footpath becomes large on the whole, can not obtain being applicable to the transfer roll that the foam bubble footpath of coloured image formation is little.

In addition, owing to conductive rubber composition fully can not be foamed, rubber hardness becomes really up to the mark, can not give the suitable good flexibility as this transfer roll to transfer roll.Therefore, such as, produce and cannot crimp under the state guaranteeing wide pinching width photoreceptor, the transfer efficiency of toning agent reduces, and photoreceptor is caused to the possible problem of damage.

When foaming insufficient in addition, also there is the minimizing that can not obtain above-mentioned explanation and form material and suppress the effect of Master Cost and lightweight and cut down the problem of the effects such as trucking costs.

On the other hand, when mixing ratio overruns, although foam bubble footpath can be diminished, rubber hardness becomes really up to the mark, can not give the suitable good flexibility as this transfer roll to transfer roll.Therefore, there is the possibility producing above-mentioned various problems.

On the other hand, by the mixing ratio of whipping agent is arranged on above-mentioned scope, guarantee the good flexibility of transfer roll, carry out foaming and the advantage brought, while this foam bubble footpath can be reduced further.

Should illustrate, consider and further improve above-mentioned effect, by the mixing ratio of whipping agent, in above-mentioned scope, also preferred total amount 100 mass parts relative to rubber components is more than more than 7 mass parts, particularly preferably 8 mass parts, preferably below 11 mass parts, preferably below 10 mass parts.

Frothing aid

As frothing aid, the decomposition temperature with the whipping agent reducing combination can be used to promote the various frothing aids of effect decomposed, such as, can enumerate urea (H as the frothing aid combined with ADCA ₂nCONH ₂) be frothing aid etc.

The mixing ratio of frothing aid is defined as relative to above-mentioned explanation foaming dosage 70 % by weight ~ 150 % by weight based on following reason.

That is, when the mixing ratio of frothing aid is less than this scope, although the good flexibility of transfer roll can be guaranteed, the effect in the reduction foam bubble footpath caused by the mechanism of above-mentioned explanation can not be obtained.Therefore, foam bubble footpath becomes large on the whole, can not obtain being applicable to the transfer roll that the foam bubble footpath of coloured image formation is little.

Should illustrate, consider and further improve above-mentioned effect, the mixing ratio of frothing aid, also preferably foam more than 80 % by weight of dosage in above-mentioned scope, be particularly preferably more than 95 % by weight, preferably less than 120 % by weight, be particularly preferably less than 105 % by weight.

Crosslinking component

Linking agent, promotor etc. can be enumerated as the crosslinking component for making rubber constituent be cross-linked.

Wherein as linking agent, such as, can enumerate the one kind or two or more of sulphur system linking agent, thiocarbamide system linking agent, triazine derivatives system linking agent, peroxidation system linking agent, various monomers etc.Wherein preferred sulphur system linking agent.

In addition powder sulphur, sulfur-containing organic compound etc. can be enumerated as sulphur system linking agent.Wherein can enumerate tetramethyl thiuram disulfide, N as sulfur-containing organic compound etc., N-morpholine double dithio etc.The particularly preferably sulphur such as powder sulphur.

The mixing ratio of sulphur is preferably more than 0.2 mass parts relative to total amount 100 mass parts of rubber components, particularly preferably more than 1 mass parts, preferably below 5 mass parts, particularly preferably below 3 mass parts.

When mixing ratio is less than this scope, the rate of crosslinking of the entirety of conductive rubber composition is slack-off, and the crosslinked time needed is elongated, the possibility that the production efficiency that there is transfer roll reduces.When overruning in addition, the Compression Set of the transfer roll after being cross-linked becomes large, there is the possibility of superfluous sulphur in periphery 4 frosting of electroconductibility bipeltate roller 1.

As promotor, such as, can enumerate inorganic accelerator or the organic promoters etc. such as white lime, magnesium oxide (MgO), plumbous oxide (PbO) one kind or two or more.

In addition as organic promoter, such as, the guanidine system promotor such as di-o-tolyl guanidine, 1,3-diphenylguanidine, 1-OTBG o tolylbiguanide, the boratory di-o-tolyl guanidinesalt of two pyrocatechols can be enumerated; The thiazole system promotor such as 2-mercaptobenzothiazole, two-2-[4-morpholinodithio based bisulfide; The sulphenamide system promotor such as N-cyclohexyl-2-[4-morpholinodithio base sulphenamide; The thiuram system promotor such as tetra methylthiuram list sulfide, tetramethyl thiuram disulfide, Thiuram disulphide, two pentylidene thiuram tetrasulfides; Thiocarbamide system promotor etc. one kind or two or more.

As promotor, from these multiple promotor, according to the kind of linking agent of combination, can promotor one kind or two or more of choice for use the best.Time such as linking agent use sulphur, as promotor preferred choice for use thiuram system's promotor and/or thiazole system promotor.

In addition promotor because of the crosslinked mechanism promoted of kind difference different, therefore preferably and use two or more.And the mixing ratio of each promotor can set arbitrarily, be preferably more than 0.1 mass parts relative to total amount 100 mass parts of rubber components, particularly preferably more than 0.5 mass parts, preferably below 5 mass parts, particularly preferably below 2 mass parts.

Also accelerating auxiliaries can be coordinated further as crosslinking component.

As accelerating auxiliaries, such as, the metallic compounds such as zinc oxide can be enumerated; The lipid acid such as stearic acid, oleic acid, cottonseed fatty acid, other existing known accelerating auxiliaries one kind or two or more.

The mixing ratio of accelerating auxiliaries can carry out suitable setting according to the kind of the kind of rubber components and combination, linking agent, promotor and combination etc.

Other

In conductive rubber composition, also can coordinate various additive as required further.As additive, such as, can enumerate sour accepting agent, softening agent, processing aid, deterioration preventing agent, weighting agent, coking preventing agent, UV light absorber, lubricant, pigment, charged preventor, fire retardant, neutralizing agent, nucleator, co-crosslinker etc.

Wherein, sour accepting agent have generate residual in transfer roll of chlorine system gas from epichloro hydrin rubber when preventing rubber components to be cross-linked and cause thus crosslinkedly to hinder, the function such as the pollution of photoreceptor.

As sour accepting agent, the various materials that acid acceptor plays a role can be used as, wherein preferably the hydrotalcite of excellent dispersion or magnesium oxide (マグサラット), particularly preferably hydrotalcite.

In addition, by hydrotalcite etc. and magnesium oxide, calcium oxide use, thus can obtain higher sour acceptable effect, further reliably can prevent the pollution of photoreceptor.

The mixing ratio of acid accepting agent is preferably more than 0.2 mass parts relative to total amount 100 mass parts of rubber components, particularly preferably more than 0.5 mass parts, preferably below 5 mass parts, particularly preferably below 2 mass parts.

When mixing ratio is less than this scope, there is the possibility that can not obtain the effect obtained by complex acid accepting agent fully.When overruning in addition, the possibility that the hardness of depositing transfer roll after cross-linking raises.

As softening agent, such as, can enumerate the various waxes etc. such as various softening agent, polar waxes such as dibutyl phthalate (DBP), dioctyl phthalate (DOP) (DOP), Tritolyl Phosphate.In addition the lipid acid etc. such as stearic acid can be enumerated as processing aid.

The mixing ratio of softening agent and/or processing aid is preferably below 5 mass parts relative to total amount 100 mass parts of rubber components.The pollution of photoreceptor is produced when preventing from when this is to such as use in image processing system transporting.In view of above-mentioned purpose, particularly preferably use plastic Semi-polarity wax.

Various age resister, antioxidant etc. can be enumerated as deterioration preventing agent.

Wherein antioxidant, the environmental factor dependence reducing the roller resistance value of transfer roll simultaneously, has the effect of the rising of roller resistance value when suppressing energising continuously.As antioxidant, such as, can enumerate nickel diethyldithiocarbamate (NOCRAC (registered trademark) NEC-P that the emerging chemical industry of imperial palace (strain) produces) nickel dibutyl dithiocarbamate (the emerging chemical industry of imperial palace (strain) NOCRAC NBC processed).

As weighting agent, such as, can enumerate zinc oxide, silicon oxide, carbon, carbon black, clay, talcum, calcium carbonate, magnesiumcarbonate, calcium hydroxide etc. one kind or two or more.

By coordinating weighting agent, the physical strength etc. of transfer roll can be improved.

In addition pass through to use conductive carbon black as weighting agent, the assimilated efficiency of the microwave of the entirety as conductive rubber composition can be improved, and transfer roll electron conduction can be given.

As conductive carbon black, preferred HAF.Because the assimilated efficiency of microwave is excellent especially, and can evenly spread in conductive rubber composition, HAF can give transfer roll uniform electron conduction as far as possible.

It is more than 5 mass parts that the mixing ratio of conductive carbon black is preferably relative to total amount 100 mass parts of rubber components, preferably below 25 mass parts, particularly preferably below 20 mass parts.

As coking preventing agent, such as, can enumerate N-cyclohexylthiophthalimide, Tetra hydro Phthalic anhydride, N-nitrosodiphenylamine int he, 2,4-phenylbenzene-4-methyl-1-pentene etc. one kind or two or more.Particularly preferably N-cyclohexylthiophthalimide.

It is more than 0.1 mass parts that the mixing ratio of coking preventing agent is preferably relative to total amount 100 mass parts of rubber components, preferably below 5 mass parts, particularly preferably below 1 mass parts.

Co-crosslinker refers to, has himself and crosslinked carries out crosslinking reaction with rubber components and by the composition of its overall high molecular effect simultaneously.

As co-crosslinker, such as can enumerate methacrylic ester or by methacrylic acid or acrylic acid metal-salt etc. represent ethylene unsaturated monomer, utilize the one kind or two or more of the multifunctional polymer class, dioxime etc. of the functional group of 1,2-polyhutadiene.

Wherein as ethylene unsaturated monomer, such as, can enumerate,

The monocarboxylic acid classes such as (a) vinylformic acid, methacrylic acid, β-crotonic acid,

The omega-dicarboxylic acids such as (b) toxilic acid, fumaric acid, methylene-succinic acid,

The ester of the unsaturated carboxylic acid class of (c) (a) (b) or acid anhydrides,

The metal-salt of (d) (a) ~ (c),

The aliphatic conjugated diene such as (e) 1,3-butadiene, isopentene, chlorbutadiene,

The aromatic ethenyl compounds such as (f) vinylbenzene, alpha-methyl styrene, Vinyl toluene, vinyl xylene, ethyl vinyl benzene, Vinylstyrene,

(g) cyanacrylate, triallylcyanurate, vinyl pyridine etc. have heterocycle vinyl compound,

(h) in addition, based compound such as vinyl cyanide such as (methyl) vinyl cyanide or α-chloro-acrylonitrile etc., propenal, formyl radical sterol, ethenyl methyl ketone, vinyl ethyl ketone, vinyl butyl ketone etc. one kind or two or more.

In addition as the ester of the unsaturated carboxylic acid class of (c), the ester of preferred monocarboxylic acid class.

As the ester of monocarboxylic acid class, such as can enumerate (methyl) methyl acrylate, (methyl) ethyl propenoate, (methyl) n-propyl, (methyl) isopropyl acrylate, (methyl) n-butyl acrylate, (methyl) isobutyl acrylate, (methyl) vinylformic acid n-pentyl ester, (methyl) isoamyl acrylate, the just own ester of (methyl) vinylformic acid, (methyl) cyclohexyl acrylate, (methyl) 2-EHA, (methyl) Octyl acrylate, (methyl) vinylformic acid ester in the different ninth of the ten Heavenly Stems, (methyl) t-butylcyclohexyl ester, (methyl) decyl acrylate, (methyl) vinylformic acid 11 ester, (methyl) acrylate, (methyl) acrylic acid alkyl esters such as (methyl) Hydroxyethyl acrylate,

(methyl) acrylic acid aminoalkyl esters such as (methyl) acrylate, (methyl) acrylate, (methyl) vinylformic acid butylaminoethyl;

(methyl) benzyl acrylate, benzoyl (methyl) vinylformic acid, allyl group (methyl) allyl acrylate etc. have (methyl) vinylformic acid of aromatic ring;

(methyl) glycidyl acrylate, (methyl) vinylformic acid methylglycidyl esters, (methyl) acrylic acid epoxy base cyclohexyl etc. have (methyl) vinylformic acid of epoxy group(ing);

N-methylol (methyl) acrylamide, γ-(methyl) acryloxypropyl Trimethoxy silane, tetrahydrofurfuryl alcohol methacrylic acid etc. have (methyl) vinylformic acid of various functional group;

Multifunctional (methyl) vinylformic acid such as two (methyl) vinylformic acid glycol ester, trimethylolpropane tris (methyl) vinylformic acid, ethene dimethacrylate (EDMA), polyethylene glycol dimethacrylate, iso-butylene ethene dimethacrylate; Etc. one kind or two or more.

Conductive rubber composition of the present invention containing each composition described above, can modulate as in the pastly.First rubber components is coordinated mastication according to the ratio of regulation, then add various additives beyond foaming ingredient, crosslinking component mixing after, finally add foaming ingredient, crosslinking component by carrying out mixingly obtaining conductive rubber composition.In mixing, such as, can use mixing roll, Banbury mixer, extrusion machine etc.

Transfer roll

Fig. 1 is the stereographic map of an example of the embodiment representing transfer roll of the present invention.

With reference to Fig. 1, the transfer roll 1 of this example is formed as the tubular of single layer structure simultaneously by conductive rubber composition of the present invention, inserts rotating shaft 3 and fix to obtain in the through hole 2 at center.

Rotating shaft 3 is such as integrally formed by metals such as aluminium, aluminium alloy, stainless steels.

Rotating shaft 3, such as, carry out machinery while carrying out being electrically connected with transfer roll 1 via the tackiness agent with electroconductibility to fix, or by large for external diameter compared with the internal diameter of through hole 2 rotating shaft is pressed into through hole 2, carries out machinery while carrying out being electrically connected with transfer roll 1 and fix, its entirety is rotated.

When manufacturing transfer roll 1, first use single-lead-screw extruding briquetting machine to be tubular by conductive rubber composition extrusion molding of the present invention, be then cut into the length of regulation, pressurizeed by compressed steam in vulcanizing boiler, heat and carry out foaming and being cross-linked.

Then use baking box etc. that foaming, crosslinked cylindrical body are carried out heating secondary crosslinking, after cooling, be ground to the external diameter of regulation.

By the random time point of rotating shaft 3 after cylindrical body cutting to grinding, through hole 2 can be inserted and is fixed.

But, preferably after cutting, first under the state that through hole 2 is inserted in rotating shaft 3, carry out secondary crosslinking and grinding.Thus, when utilizing secondary crosslinking, dilation can prevent bending, the distortion of cylindrical body → transfer roll 1.In addition, by by rotating shaft 3 along central rotation, while grinding can improve the operability of this grinding, and the vibration of periphery 4 can be suppressed.

Rotating shaft large for external diameter compared with the internal diameter of through hole 2 is pressed into through hole 2 or via the Thermocurable tackiness agent with electroconductibility, the cylindrical body 7 before secondary crosslinking is inserted through hole 2 by rotating shaft 3 as described above.

In the situation of the latter, by heating in an oven by while cylindrical body 7 secondary crosslinking, Thermocurable tackiness agent is solidified, be mechanically secured while this rotating shaft 3 is carried out being electrically connected with cylindrical body → transfer roll 1.

In addition, in the former situation, electrical connection is completed while press-in and machinery is fixed.

Foam bubble footpath

Consider and be used in the formation of the coloured image of above-mentioned explanation by transfer roll 1, the foam bubble footpath of the foam bubble exposed at periphery 4 after grinding is less than 300 μm, particularly preferably less than 250 μm.

The lower limit in foam bubble footpath is not particularly limited, and preferably more than 100 μm, is particularly preferably more than 150 μm.When foam bubble footpath is less than this scope, there is rubber hardness and become really up to the mark, the suitable good flexibility as this transfer roll can not be given to transfer roll.

In addition, when foam bubble footpath is too small, also there is the minimizing that can not obtain above-mentioned explanation and form material and suppress the effect of Master Cost and lightweight and cut down the problem of the effects such as trucking costs.

Foam bubble footpath, uses the mean value in the foam bubble footpath of measurement microscope to represent by the multiple sites at periphery 4.

Other characteristics

The rubber hardness of transfer roll 1, according to the measuring method that (society) Japan rubber association criterion specification SRIS 0101 " physical test method of expanded rubber " specifies, under the ambient temperature and moisture environment of temperature 23 ± 1 DEG C, relative humidity 55 ± 1%, apply 500gf (≒ 4.9N) load and the ASKER C type hardness tester that measures represents, be preferably less than 45 °, particularly preferably less than 34 °.

The hard transfer roll that rubber hardness overruns, because its flexibility is inadequate, crimps under the state cannot guaranteeing wide pinching width to photoreceptor, and the transfer efficiency that there is toning agent reduces, and photoreceptor is caused to the possibility of damage.

The lower limit of rubber hardness is not particularly limited, and represents preferably more than 20 °, particularly preferably more than 24 ° by above-mentioned ASKER C type hardness tester.

Rubber hardness is less than the transfer roll of the softness of this scope, and due to its insufficient strength, the pinching pressure that cannot specify photoreceptor crimps, and the transfer efficiency that therefore there is toning agent reduces, the possibility of abrasion in the short period of time.

On the other hand, by the rubber hardness of transfer roll is controlled in above-mentioned scope, at short notice can not abrasion, damage can not be caused to photoreceptor, by this transfer roll, photoreceptor suitable pinching pressure and pinching width are crimped, the reduction of the transfer efficiency of toning agent can be prevented.

In addition transfer roll 1 measure under the ambient temperature and moisture environment of temperature 23 ± 1 DEG C, relative humidity 55 ± 1%, the roller resistance value applied under voltage 1000V is 10 ¹⁰below Ω, particularly preferably 10 ⁹below Ω.

And, transfer roll 1 can be adjusted to the Compression Set, tangent of the dielectric loss angle etc. with regulation.

In order to adjust Compression Set, ASKER C type hardness tester, roller resistance value and tangent of the dielectric loss angle etc., such as, can adjust kind and the amount of each composition of composition conductive rubber composition.

Image processing system

The feature of image processing system of the present invention is transfer roll of the present invention is housed.As the image processing system of the invention described above, such as, can enumerate the various image processing systems that laser printer, xerographic printer, plain paper facsimile or these compounding machine etc. utilize Xxerography.

Particularly as image processing system of the present invention, the above-mentioned explanatorily preferred like that colored machine toner image of the multiple colors such as cyan, magenta and yellow overlap being formed coloured image.

As above-mentioned colored machine, there is the colored machine of the visualization unit around 1 photoreceptor with corresponding each colour toners, each color has respective photoreceptor and its colored machine of various modes of colored machine etc. of visualization unit corresponding, can be the colored machine of above-mentioned any-mode.

In arbitrary situation, as the transfer roll installed in respective visualization unit, by adopting transfer roll of the present invention, meet the requirement of cost cutting, lightweight etc., while the confusion of the coloured image formed can be prevented and improve image quality.

Embodiment

Embodiment 1

The modulation of conductive rubber composition

ECO (HYDRIN (registered trademark) T3108 that Japanese Zeon (strain) produces) 20 mass parts, EPDM (Esprene (registered trademark) 505A that Sumitomo Chemical (strain) produces) 10 mass parts and SBR (JSR 1502 that JSR (strain) produces, non-oil-filled) 70 mass parts are coordinated as rubber components.

Then at total amount 100 mass parts cooperation each composition as described in Table 1 of these rubber components, the mixing modulation conductive rubber composition of Banbury mixer is used.

[table 1]

Composition	Mass parts
		Weighting agent	10
Whipping agent	4
		Frothing aid	4
Acid accepting agent	1
		Linking agent	1.6
Altax	1.5
		Promotor TS	0.5
Accelerating auxiliaries I	1
		Accelerating auxiliaries II	5

Each composition in table 1 is as shown in following.Should illustrate, the mass parts in table 1 is the mass parts of total amount 100 mass parts relative to rubber components.

Weighting agent: carbon black HAF (the trade(brand)name Seast3 that East Sea Carbon (strain) produces)

Whipping agent: ADCA (Yonghe County changes into the trade(brand)name VINYFOR AC#3 that industry (strain) is produced)

Frothing aid: Urea Series frothing aid (Yonghe County changes into the trade(brand)name abscess Paste101 that industry (strain) is produced)

Acid accepting agent: hydrotalcite (DHT-4A-2 that consonance chemical industry (strain) is produced)

Linking agent: powder sulphur (crane sees that chemical industry (strain) produces)

Altax: two-2-[4-morpholinodithio based bisulfide (the trade(brand)name SUNSINE MBTS that Shandong Shanxian Chemical Co.Ltd. produces)

Promotor TS: tetramethyl thiuram disulfide (Sanceller (registered trademark) TS that three new chemical industry (strain) are produced)

Accelerating auxiliaries I: stearic acid (the trade(brand)name TSUBAKI produced day oil (strain), doubles as processing aid.)

Accelerating auxiliaries II: 2 kinds, zinc oxide (Mitsui Metal Co., Ltd.'s mining industry (strain) product)

The mixing ratio of Urea Series frothing aid is 100 % by weight of foaming dosage.

The manufacture of transfer roll

The conductive rubber composition of modulation is supplied in single-lead-screw extruding briquetting machine, and extrusion molding is cut into the length of regulation after being the cylindrical shape of external diameter φ 10mm, internal diameter φ 3.0mm, installs the crosslinked pre-rotating shaft of external diameter φ 2.2mm.

Then in vulcanizing boiler, undertaken 120 DEG C × 10 minutes by compressed steam, the pressurization of then 160 DEG C × 20 minutes, heating, by cylindrical body, the gas produced by the decomposition of whipping agent carries out foaming simultaneously, and rubber components is cross-linked.The external diameter of the cylindrical body after foaming is φ 35mm.

Then this cylindrical body is installed on the rotating shaft 3 of the external diameter φ 5mm of the Thermocurable tackiness agent of periphery applying conductive, in baking box, heating is carried out secondary crosslinking for 160 DEG C × 60 minutes simultaneously, Thermocurable tackiness agent is solidified, carries out being electrically connected with rotating shaft 3 and carry out machinery and fix.

Then after being cut at the two ends of cylindrical body, by its periphery 4, by using cylinder shredder to carry out longitudinal grinding, external diameter becomes φ 12.5mm (tolerance+0.1mm) the most at last, manufactures transfer roll 1.

Embodiment 2

The mixing ratio of the ADCA as whipping agent being set to relative to total amount 100 mass parts of rubber components is 6 mass parts, and the mixing ratio of Urea Series frothing aid to be set to relative to total amount 100 mass parts of rubber components be 6 mass parts, in addition, modulate conductive rubber composition identically with embodiment 1, manufacture transfer roll 1.

Embodiment 3

The mixing ratio of the ADCA as whipping agent being set to relative to total amount 100 mass parts of rubber components is 8 mass parts, and the mixing ratio of Urea Series frothing aid to be set to relative to total amount 100 mass parts of rubber components be 8 mass parts, in addition, modulate conductive rubber composition identically with embodiment 1, manufacture transfer roll 1.

Embodiment 4

The mixing ratio of the ADCA as whipping agent being set to relative to total amount 100 mass parts of rubber components is 10 mass parts, and the mixing ratio of Urea Series frothing aid to be set to relative to total amount 100 mass parts of rubber components be 10 mass parts, in addition, modulate conductive rubber composition identically with embodiment 1, manufacture transfer roll 1.

Embodiment 5

The mixing ratio of the ADCA as whipping agent being set to relative to total amount 100 mass parts of rubber components is 12 mass parts, and the mixing ratio of Urea Series frothing aid to be set to relative to total amount 100 mass parts of rubber components be 12 mass parts, modulate conductive rubber composition in addition identically with embodiment 1, manufacture transfer roll 1.

Embodiment 6

The mixing ratio of the ADCA as whipping agent being set to relative to total amount 100 mass parts of rubber components is 8 mass parts, and the mixing ratio of Urea Series frothing aid to be set to relative to total amount 100 mass parts of rubber components be 6 mass parts, in addition, modulate conductive rubber composition identically with embodiment 1, manufacture transfer roll 1.

The mixing ratio of Urea Series frothing aid is 75 % by weight of foaming dosage.

Embodiment 7

The mixing ratio of the ADCA as whipping agent being set to relative to total amount 100 mass parts of rubber components is 8 mass parts, and the mixing ratio of Urea Series frothing aid to be set to relative to total amount 100 mass parts of rubber components be 10 mass parts, in addition, modulate conductive rubber composition identically with embodiment 1, manufacture transfer roll 1.

The mixing ratio of Urea Series frothing aid is 125 % by weight of foaming dosage.

Embodiment 8

The mixing ratio of the ADCA as whipping agent being set to relative to total amount 100 mass parts of rubber components is 8 mass parts, and the mixing ratio of Urea Series frothing aid to be set to relative to total amount 100 mass parts of rubber components be 12 mass parts, in addition, modulate conductive rubber composition identically with embodiment 1, manufacture transfer roll 1.

The mixing ratio of Urea Series frothing aid is 150 % by weight of foaming dosage.

Embodiment 9

As rubber components, coordinate and use identical ECO20 mass parts, EPDM10 mass parts, SBR40 mass parts in embodiment 1 and then coordinate NBR (the JSR N250SL that JSR (strain) produces, non-oil-filled, low butyronitrile NBR, acrylonitrile content: 20%) 30 mass parts, in addition, modulate conductive rubber composition identically with embodiment 3, and manufacture transfer roll 1.

Comparative example 1

The mixing ratio of the ADCA as whipping agent being set to relative to total amount 100 mass parts of rubber components is 3 mass parts, and the mixing ratio of Urea Series frothing aid to be set to relative to total amount 100 mass parts of rubber components be 3 mass parts, in addition, modulate conductive rubber composition identically with embodiment 1, manufacture transfer roll 1.

Comparative example 2

The mixing ratio of the ADCA as whipping agent being set to relative to total amount 100 mass parts of rubber components is 13 mass parts, and the mixing ratio of Urea Series frothing aid to be set to relative to total amount 100 mass parts of rubber components be 13 mass parts, in addition, modulate conductive rubber composition identically with embodiment 1, manufacture transfer roll 1.

Comparative example 3

The mixing ratio of the ADCA as whipping agent being set to relative to total amount 100 mass parts of rubber components is 8 mass parts, and the mixing ratio of Urea Series frothing aid to be set to relative to total amount 100 mass parts of rubber components be 5 mass parts, in addition, modulate conductive rubber composition identically with embodiment 1, manufacture transfer roll 1.

The mixing ratio of Urea Series frothing aid is 62.5 % by weight of foaming dosage.

Comparative example 4

The mixing ratio of the ADCA as whipping agent being set to relative to total amount 100 mass parts of rubber components is 8 mass parts, and the mixing ratio of Urea Series frothing aid to be set to relative to total amount 100 mass parts of rubber components be 13 mass parts, in addition, modulate conductive rubber composition identically with embodiment 1, manufacture transfer roll 1.

The mixing ratio of Urea Series frothing aid is 162.5 % by weight of foaming dosage.

The mensuration in foam bubble footpath

The transfer roll 1 manufactured in embodiment, comparative example, the foam bubble footpath of foam bubble that periphery 4 after grinding exposes, by the multiple sites at this periphery 4, use measurement microscope foam bubble footpath, obtain its mean value, as foam bubble footpath.Then according to following standard, the size in foam bubble footpath is evaluated.

◎: foam bubble footpath is less than 250 μm.

Zero: foam bubble footpath is more than 250 μm, is less than 300 μm.

×: foam bubble footpath is more than 300 μm.

Rubber hardness is evaluated

Under the ambient temperature and moisture environment of temperature 23 ± 1 DEG C, relative humidity 55 ± 1%, be determined at the ASKERC type hardness tester of the transfer roll 1 manufactured in embodiment, comparative example according to the measuring method of above-mentioned explanation.Then by ASKERC type hardness tester be less than 34 ° to be evaluated as extremely good (◎), more than 34 ° and the scope inner evaluation of less than 45 ° be well (zero), be evaluated as bad (×) more than 45 °.Above result is shown by table 2 ~ table 4.

[table 2]

[table 3]

[table 4]

According to the result of the comparative example 1 of table 4, when the mixing ratio of known whipping agent is less than 4 mass parts relative to total amount 100 mass parts of rubber components, foam bubble footpath becomes large on the whole, cannot obtain the transfer roll that the foam bubble footpath of the formation being suitable for coloured image is little.

In addition according to the result of comparative example 2, the mixing ratio of whipping agent relative to total amount 100 mass parts of rubber components more than 12 mass parts time, although foam bubble footpath can be diminished, rubber hardness becomes really up to the mark, can not give the suitable good flexibility as this transfer roll to transfer roll.

According to the result of comparative example 3, when the mixing ratio of known frothing aid is less than 70 % by weight of foaming dosage, although can guarantee good flexibility, foam bubble footpath becomes large on the whole, cannot obtain the transfer roll that the foam bubble footpath of the formation being suitable for coloured image is little.

And according to the result of comparative example 4, when the mixing ratio of frothing aid exceedes 150 % by weight of foaming dosage, although foam bubble footpath can be diminished, rubber hardness becomes really up to the mark, the suitable good flexibility as this transfer roll can not be given to transfer roll.

On the other hand, according to table 2,3 the result of embodiment 1 ~ 9, the mixing ratio of known whipping agent is 4 mass parts ~ 12 mass parts relative to total amount 100 mass parts of rubber components, and the mixing ratio of frothing aid be foaming dosage 70 % by weight ~ 120 % by weight time, while can obtaining flexibility excellence, be suitable for the transfer roll that the foam bubble footpath of the formation of coloured image is little.

In addition, according to the result of embodiment 1 ~ 8, foam bubble footpath is reduced further while known consideration improves the flexibility of transfer roll, the mixing ratio of whipping agent in above-mentioned scope also preferred total amount 100 mass parts relative to rubber components be more than 7 mass parts, particularly preferably more than 8 mass parts, preferably below 11 mass parts, preferably below 10 mass parts.In addition the mixing ratio of frothing aid also preferably foams more than 80 % by weight of dosage in above-mentioned scope, and particularly preferably more than 95 % by weight, preferably less than 120 % by weight, particularly preferably less than 105 % by weight.

And, the periphery of embodiment 3,9 is more known by coordinating polar rubber, the degree of uniformity further uniform vesicular structure of foaming can be formed.

Claims

1. a conductive rubber composition, it is characterized in that, can be pressurizeed by compressed steam in vulcanizing boiler, heat and carry out foaming and being cross-linked, contain: at least containing the rubber components of styrene butadiene ribber, ethylene propylene diene rubber and epichloro hydrin rubber, for the foaming ingredient that described rubber components foams by the crosslinking component that is cross-linked by described rubber components and being used for; Further, described foaming ingredient contains in total amount 100 mass parts of every described rubber components the frothing aid that be 4 mass parts ~ 12 mass parts, produced the whipping agent of gas and 70 % by weight ~ 150 % by weight of described foaming dosage by thermal degradation the described whipping agent of promotion is decomposed.

2. conductive rubber composition according to claim 1, wherein, described rubber components is further containing the polar rubber of at least a kind that is selected from acrylonitrile butadiene rubber, chloroprene rubber, divinyl rubber and acrylic rubber.

3. a transfer roll, is characterized in that, is made up of the conducting rubber described in claim 1 or 2.

4. transfer roll according to claim 3, to be through described conductive rubber composition extrusion molding be tubular, by compressed steam pressurization, heating and carry out the operation manufacture foamed and be cross-linked in vulcanizing boiler.

5. an image processing system, is characterized in that, has installed the transfer roll described in claim 3 or 4.