JP2012198328A - Method of manufacturing intermediate transfer body, intermediate transfer body, and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing an intermediate transfer body that reduces unevenness of adhesion of particles and suppresses density unevenness of an image transferred from the intermediate transfer body to a recording medium, an intermediate transfer body manufactured with the manufacturing method, and an image forming apparatus including the intermediate transfer body.SOLUTION: A method of manufacturing an intermediate transfer body 38 used for an image forming apparatus includes: a particle adhesion step of causing particles 13 to be adhered to the surface of an elastic layer 12 that is formed on a substrate 11, and a particle fixation step of fixing the particles 13 adhered to the surface of the elastic layer 12 to the surface of the elastic layer 12. In the particle adhesion step, the particles 13 are drawn by electrostatic force and adhered to the surface of the elastic layer 12.

Description

  The present invention relates to a method for manufacturing an intermediate transfer member used in an image forming apparatus such as a copying machine, a facsimile machine, or a printer, an intermediate transfer member manufactured by the manufacturing method, and an image forming apparatus including the intermediate transfer member.

  An image forming apparatus using an intermediate transfer belt as an intermediate transfer member is a color image forming apparatus or a multicolor image forming apparatus that outputs a color print by sequentially laminating and transferring a plurality of color component images of color image information and multicolor image information. Useful as. Conventionally, as this type of image forming apparatus, many image forming apparatuses using an intermediate transfer belt formed of a resin such as polyimide resin or polyamideimide resin have been provided.

  However, the intermediate transfer belt formed of resin generally has high hardness. For this reason, for example, in the primary transfer step of the toner image from the photosensitive member as the image carrier to the intermediate transfer belt and the secondary transfer step of the toner image from the intermediate transfer belt to the recording medium, Due to the stress concentration in the central portion, a transfer failure called a so-called character dropout phenomenon is likely to occur.

  As one of methods for improving the above-described character dropout phenomenon, it has been proposed to make the surface of the intermediate transfer belt elastic. That is, since the surface of the intermediate transfer belt is elasticized, the surface of the intermediate transfer belt is freely deformed according to the thickness of the toner image, so that stress concentration on the toner image is reduced and the transfer failure is improved. The Therefore, in order to eliminate such transfer defects, an intermediate transfer belt in which an elastic layer made of a flexible material such as rubber is formed on a base material is used.

  However, since the surface of the intermediate transfer belt is an elastic layer, the lowermost layer portion of the toner transferred from the photosensitive member to the surface of the intermediate transfer belt adheres to the surface of the intermediate transfer belt due to the adhesiveness of the elastic layer. It remains on the surface of the intermediate transfer belt without being transferred to the recording medium. Therefore, an image density shortage due to a decrease in transfer efficiency of toner from the intermediate transfer belt to the recording medium, and an image defect due to an image dropout may occur.

  In Patent Document 1, there is a particle adhesion process for adhering particles to the elastic layer surface, which is the surface of an intermediate transfer belt having an elastic layer formed on a base material, and the particles adhered to the elastic layer surface are fixed to the elastic layer surface. An intermediate transfer belt manufacturing method having a particle fixing step is disclosed. In the particle adhering step, a contact member is applied to the surface of the elastic layer, particles are introduced into a contact portion between the elastic layer surface and the contact member, and the intermediate transfer belt is rotated to rub the elastic layer surface and the contact member. By doing so, the particles put into the contact portion are adhered to the elastic layer surface by frictional contact. In the particle fixing step, the particles attached to the elastic layer surface in the particle attaching step are fixed to the elastic layer surface by being pushed into the elastic layer by the contact member. In this way, by attaching particles to the elastic layer surface, the exposed area of the elastic layer surface can be reduced and the adhesiveness of the elastic layer can be reduced, so that the toner remaining on the surface of the intermediate transfer belt during transfer is reduced and transferred. It is said that efficiency can be improved.

  However, in the method of manufacturing the intermediate transfer belt described in Patent Document 1, when particles are adhered to the elastic layer surface, the particles are aggregated and unevenly distributed due to mechanical force due to the frictional contact or the like. It was difficult to make particles uniformly present on the surface of the layer. Therefore, the transfer performance also varies due to uneven adhesion of particles on the surface of the elastic layer, and there arises a problem that density unevenness occurs in the toner image transferred from the intermediate transfer belt to the recording medium.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an intermediate transfer body that can reduce unevenness of particle adhesion on the surface of the elastic layer and suppress density unevenness of an image transferred from the intermediate transfer body to a recording medium. A manufacturing method, an intermediate transfer member produced by the manufacturing method, and an image forming apparatus provided with the intermediate transfer member.

In order to achieve the above object, the invention of claim 1 includes a particle attaching step for attaching particles to the surface of an elastic layer formed on a substrate, and particles attached to the surface of the elastic layer. A method for producing an intermediate transfer member used in an image forming apparatus, wherein the particles are attracted and adhered to the surface of the elastic layer by electrostatic force in the particle adhesion step. It is characterized by this.
According to a second aspect of the present invention, in the method for producing an intermediate transfer member according to the first aspect, the particle coating agent is exchanged with the intermediate transfer member by a rotating body that supports on the surface a particle coating agent in which the particles and the magnetic particles are mixed. An electrostatic force is generated by an electric field that attracts the particles from the rotating body formed in the facing area to the intermediate transfer body side due to a potential difference between the rotating body and the intermediate transfer body. To move the particles from the rotating body toward the intermediate transfer member, and attach the particles to the surface of the elastic layer.
The invention according to claim 3 is the method for producing an intermediate transfer member according to claim 2, wherein the concentration A of the particles is 5 [wt%] ≦ A ≦ 10 [wt%] with respect to the total weight of the particle coating agent. ].
According to a fourth aspect of the present invention, in the method for producing an intermediate transfer member according to the first, second, or third aspect, the volume average particle size of the particles is 0.5 [μm] to 5.0 [μm]. It is a feature.
The invention of claim 5 is the method for producing an intermediate transfer member according to claim 1, 2, 3 or 4, wherein the projected area ratio of the exposed portion of the particles in the elastic layer is 60 [%] or more. It is a feature.
According to a sixth aspect of the invention, in the method for producing an intermediate transfer member according to the first, second, third, fourth or fifth aspect, the particles are silicone resin fine particles.
The invention according to claim 7 is the method for producing the intermediate transfer member according to claim 1, 2, 3, 4, 5 or 6, wherein at least a part of the particles adhered to the surface of the elastic layer in the particle adhesion step. The elastic layer is softened so as to be impregnated, and the elastic layer is heated and cured in the particle fixing step to fix the particles to the surface of the elastic layer.
The invention according to claim 8 is an image bearing member for forming an electrostatic latent image on the surface, a developing means for developing the electrostatic latent image on the image bearing member with a developer, and the developing means developed with the developing means. An intermediate transfer member to which an image on the image carrier is transferred, a primary transfer for transferring the image on the image carrier onto the intermediate transfer member, and an image on the intermediate transfer member on a recording medium. An intermediate transfer member used in an image forming apparatus that performs secondary transfer to be transferred to the intermediate transfer member, wherein the intermediate transfer member is manufactured by the method of manufacturing an intermediate transfer member according to claim 1, 2, 3, 4, 5, 6, or 7. It is characterized by being made.
According to a ninth aspect of the present invention, there is provided an image carrier that forms an electrostatic latent image on the surface, a developing unit that develops the electrostatic latent image on the image carrier with a developer, and the development unit that develops the electrostatic latent image. An intermediate transfer member to which an image on the image carrier is transferred, a primary transfer for transferring the image on the image carrier onto the intermediate transfer member, and an image on the intermediate transfer member as a recording medium In the image forming apparatus for performing the secondary transfer to be transferred on, the intermediate transfer member according to claim 8 is used as the intermediate transfer member.

  In the present invention, the particles are attracted and adhered to the elastic layer surface by electrostatic force, so that an amount of particles according to the magnitude of the electrostatic force can be adhered at each location on the elastic layer surface. . As a result, when the particles are adhered to the surface of the elastic layer, the particles are not agglomerated and unevenly distributed due to mechanical force due to frictional contact as in the prior art. Can be uniformly present, and uneven adhesion of particles on the surface of the elastic layer can be reduced. Accordingly, the variation in transfer performance due to the uneven adhesion of particles on the surface of the elastic layer can be suppressed, and the occurrence of uneven density in the image transferred from the intermediate transfer member to the recording medium can be suppressed.

  As described above, according to the present invention, there is an excellent effect that unevenness in adhesion of particles on the surface of the elastic layer can be reduced and unevenness in density of an image transferred from an intermediate transfer member to a recording medium can be suppressed.

The schematic diagram of a particle | grain coating apparatus. FIG. 2 is a schematic diagram of a main part of the image forming apparatus according to the embodiment. FIG. 3 is a schematic diagram illustrating a main part of a configuration example of an image forming apparatus in which a plurality of photosensitive drums are arranged along one intermediate transfer belt. FIG. 3 is a schematic diagram of a layer configuration of an intermediate transfer belt. FIG. 3 is a schematic diagram of a cross section of an intermediate transfer belt having an elastic layer containing a plurality of particles in the thickness direction. The schematic diagram of the apparatus for producing a base layer and an elastic layer.

  FIG. 2 is a schematic diagram of a main part for explaining an image forming apparatus equipped with a seamless belt obtained by the method for producing an intermediate transfer member according to the present invention as a belt member.

  The intermediate transfer unit 500 including the belt member shown in FIG. 2 includes an intermediate transfer belt 501 that is an intermediate transfer member stretched around a plurality of rollers. Around the intermediate transfer belt 501 are a secondary transfer bias roller 605 that is a secondary transfer charge applying unit of the secondary transfer unit 600, a belt cleaning blade 504 that is an intermediate transfer member cleaning unit, and a lubricant for a lubricant application unit. A lubricant application brush 505 or the like that is an application member is disposed so as to face each other.

  A position detection mark (not shown) is provided on the outer peripheral surface or the inner peripheral surface of the intermediate transfer belt 501. However, on the outer peripheral surface side of the intermediate transfer belt 501, it is necessary to devise a position detection mark that avoids the passing area of the belt cleaning blade 504, which may be difficult to arrange. A position detection mark may be provided on the inner peripheral surface side of the intermediate transfer belt 501. An optical sensor 514 serving as a mark detection sensor is provided at a position between the primary transfer bias roller 507 and the belt driving roller 508 where the intermediate transfer belt 501 is bridged.

  The intermediate transfer belt 501 includes a primary transfer bias roller 507, a belt driving roller 508, a belt tension roller 509, a secondary transfer counter roller 510, a cleaning counter roller 511, and a feedback current detection roller 512 serving as a primary transfer charge applying unit. It is stretched. Each roller is made of a conductive material, and each roller other than the primary transfer bias roller 507 is grounded. The primary transfer bias roller 507 is applied with a transfer bias controlled to a predetermined current or voltage according to the number of superimposed toner images from a constant current or constant voltage controlled primary transfer power supply 801. .

  The intermediate transfer belt 501 is driven in the arrow direction by a belt driving roller 508 that is driven to rotate in the arrow direction by a drive motor (not shown).

  The intermediate transfer belt 501 as a belt member is usually a semiconductor or an insulator and has a single-layer or multi-layer structure. However, in the present invention, a seamless belt is preferably used, thereby improving durability. Excellent image formation can be realized. Further, the intermediate transfer belt 501 is set to be larger than the maximum sheet passing size in order to superimpose the toner images formed on the photosensitive drum 200.

  A secondary transfer bias roller 605 as a secondary transfer unit is connected to a belt outer peripheral surface of the intermediate transfer belt 501 stretched by the secondary transfer counter roller 510 by a contact / separation mechanism, which will be described later. It is configured to be able to contact and separate. The secondary transfer bias roller 605 is disposed so as to sandwich the transfer paper P, which is a recording medium, between a portion of the intermediate transfer belt 501 stretched around the secondary transfer counter roller 510 and a constant current. A transfer bias having a predetermined current is applied by a secondary transfer power source 802 to be controlled.

  The registration roller 610 feeds the transfer paper P, which is a transfer material, between the intermediate transfer belt 501 stretched around the secondary transfer counter roller 510 and the secondary transfer bias roller 605 at a predetermined timing. Further, a cleaning blade 608 as a cleaning unit is in contact with the secondary transfer bias roller 605. The cleaning blade 608 is for removing the adhering matter adhering to the surface of the secondary transfer bias roller 605 for cleaning.

  In the color copying machine having such a configuration, when an image forming cycle is started, the photosensitive drum 200 is rotated in a counterclockwise direction indicated by an arrow by a drive motor (not shown), and on the photosensitive drum 200, Bk (black ) Toner image formation, C (cyan) toner image formation, M (magenta) toner image formation, and Y (yellow) toner image formation are performed. The intermediate transfer belt 501 is rotated clockwise by the belt driving roller 508 as indicated by an arrow. As the intermediate transfer belt 501 rotates, the primary transfer of the Bk toner image, the C toner image, the M toner image, and the Y toner image is performed by the transfer bias due to the voltage applied to the primary transfer bias roller 507. In addition, toner images are formed on the intermediate transfer belt 501 in the order of Bk, C, M, and Y.

For example, the Bk toner image formation is performed as follows.
In FIG. 2, a charging charger 203 uniformly charges the surface of the photosensitive drum 200 to a predetermined potential with a negative charge by corona discharge. The timing is determined based on the belt mark detection signal, and raster exposure with laser light is performed based on the Bk color image signal by a writing optical unit (not shown). When this raster image is exposed, the charge proportional to the exposure light amount disappears in the exposed portion of the surface of the photosensitive drum 200 that is initially uniformly charged, and a Bk electrostatic latent image is formed. When the negatively charged Bk toner on the developing roller of the developing device 231Bk comes into contact with this Bk electrostatic latent image, the toner does not adhere to the remaining portion of the photosensitive drum 200 and there is no charge. The toner is attracted to the portion, that is, the exposed portion, and a Bk toner image similar to the electrostatic latent image is formed.

  The Bk toner image formed on the photosensitive drum 200 in this manner is primarily transferred to the belt outer peripheral surface of the intermediate transfer belt 501 that is rotating at a constant speed while being in contact with the photosensitive drum 200. Some untransferred residual toner remaining on the surface of the photosensitive drum 200 after the primary transfer is cleaned by the photosensitive member cleaning device 201 in preparation for the reuse of the photosensitive drum 200. On the photosensitive drum 200 side, the process proceeds to the C image forming process after the Bk image forming process, and reading of C image data by a color scanner starts at a predetermined timing. By writing laser light with the C image data, the photosensitive drum A C electrostatic latent image is formed on the surface of 200.

  Then, after the rear end portion of the previous Bk electrostatic latent image passes and before the front end portion of the C electrostatic latent image reaches, the revolver developing unit 230 is rotated, and the developing device 231C is moved to the developing position. The C electrostatic latent image is developed with C toner. Thereafter, development of the C electrostatic latent image area is continued, but when the rear end of the C electrostatic latent image passes, the revolver developing unit is rotated in the same manner as in the case of the developing device 231Bk, and the next The developing device 231M is moved to the developing position. This is also completed before the leading edge of the next Y electrostatic latent image reaches the developing position. Note that the M and Y image forming steps are the same as the Bk and C steps described above because the operations of reading color image data, forming an electrostatic latent image, and developing are the same as those described above.

  The Bk, C, M, and Y toner images sequentially formed on the photosensitive drum 200 in this manner are sequentially aligned on the same surface on the intermediate transfer belt 501 and primarily transferred. As a result, a toner image having a maximum of four colors superimposed on the intermediate transfer belt 501 is formed. On the other hand, at the time when the image forming operation is started, the transfer paper P is fed from a paper feed unit such as a transfer paper cassette or a manual feed tray, and is waiting at the nip of the registration roller 610.

  When the leading edge of the toner image on the intermediate transfer belt 501 approaches the secondary transfer portion where the nip is formed by the intermediate transfer belt 501 stretched around the secondary transfer counter roller 510 and the secondary transfer bias roller 605. Then, the registration roller 610 is driven so that the leading edge of the transfer paper P coincides with the leading edge of the toner image, and the transfer paper P is conveyed along the transfer paper guide plate 601 to register the transfer paper P and the toner image. Matching is done.

  In this way, when the transfer paper P passes through the secondary transfer portion, the four-color superimposed toner image on the intermediate transfer belt 501 is transferred by the transfer bias applied by the secondary transfer power source 802 to the secondary transfer bias roller 605. Are collectively transferred (secondary transfer) onto the transfer paper P. After the transfer paper P is conveyed along the transfer paper guide plate 601 and passed through a portion facing the transfer paper neutralization charger 606 composed of a static elimination needle disposed on the downstream side of the secondary transfer portion, it is neutralized. Then, the toner is fed toward the fixing device 270 by the belt conveyance device 210 which is a belt component. Then, after the toner image is melted and fixed at the nip portions of the fixing rollers 271 and 272 of the fixing device 270, the transfer paper P is sent out of the apparatus main body by a discharge roller (not shown), and is stacked face up on a copy tray (not shown). Is done. Note that the fixing device 270 may be configured to include a belt component if necessary.

  On the other hand, the surface of the photosensitive drum 200 after the belt transfer is cleaned by the photosensitive member cleaning device 201 and is uniformly discharged by the discharging lamp 202. Further, residual toner remaining on the outer peripheral surface of the intermediate transfer belt 501 after the toner image is secondarily transferred to the transfer paper P is cleaned by the belt cleaning blade 504. The belt cleaning blade 504 is configured to be brought into contact with and separated from the belt outer peripheral surface of the intermediate transfer belt 501 at a predetermined timing by a cleaning member separating and contacting mechanism (not shown).

  On the upstream side of the belt cleaning blade 504 in the movement direction of the intermediate transfer belt 501, a toner seal member 502 that is in contact with and away from the outer peripheral surface of the intermediate transfer belt 501 is provided. The toner seal member 502 receives the falling toner that has dropped from the belt cleaning blade 504 during cleaning of the residual toner, and prevents the falling toner from scattering on the transfer path of the transfer paper P. The toner seal member 502 is brought into contact with and separated from the belt outer peripheral surface of the intermediate transfer belt 501 together with the belt cleaning blade 504 by the cleaning member separating and contacting mechanism.

  The lubricant 506 scraped by the lubricant application brush 505 is applied to the outer peripheral surface of the intermediate transfer belt 501 from which the residual toner has been removed in this way. The lubricant 506 is made of, for example, a solid material such as zinc stearate, and is disposed so as to come into contact with the lubricant application brush 505. The residual charge remaining on the outer peripheral surface of the intermediate transfer belt 501 is removed by a neutralizing bias applied by a belt neutralizing brush (not shown) that is in contact with the outer peripheral surface of the intermediate transfer belt 501. Here, the lubricant application brush 505 and the belt neutralizing brush are brought into contact with and separated from the belt outer peripheral surface of the intermediate transfer belt 501 at a predetermined timing by respective contact and separation mechanisms (not shown).

  Here, at the time of repeat copy, the operation of the color scanner and the image formation on the photosensitive drum 200 are performed at a predetermined timing following the first color (Y) image formation process of the first sheet and the first color of the second sheet. The process proceeds to the image forming process (Bk). Further, the intermediate transfer belt 501 has a second Bk toner image in a region cleaned by the belt cleaning blade 504 on the outer peripheral surface of the belt following the batch transfer process of the first four-color superimposed toner image to the transfer paper. To be primarily transferred. After that, the operation is the same as the first sheet.

  The above is a copy mode for obtaining a four-color full-color copy. In the three-color copy mode and the two-color copy mode, the same operation as described above is performed for the designated color and the number of times. In the single color copy mode, only the developing device of the predetermined color of the revolver developing unit 230 is set in the developing operation state until the predetermined number of sheets is completed, and the belt cleaning blade 504 is kept in contact with the intermediate transfer belt 501. The copy operation is performed in the state.

  In the above-described embodiment, the copying machine having only one photosensitive drum has been described. However, the present invention can seamlessly include a plurality of photosensitive drums as shown in a configuration example in the schematic diagram of the main part in FIG. The present invention can also be applied to an image forming apparatus arranged side by side along one intermediate transfer belt made of a belt.

  FIG. 3 shows a configuration of a four-drum type digital color printer including four photosensitive drums 21Bk, 21Y, 21M, and 21C for forming toner images of four different colors (black, yellow, magenta, and cyan). An example is shown.

  In FIG. 3, the printer body 10 includes an image writing unit 17, an image forming unit 18, and a paper feeding unit 19 for performing color image formation by an electrophotographic method. Based on the image signal, the image processing unit performs image processing to convert it into black (Bk), magenta (M), yellow (Y), and cyan (C) color signals for image formation, and transmits them to the image writing unit 17. To do. The image writing unit 17 is a laser scanning optical system including, for example, a laser light source, a deflector such as a rotary polygon mirror, a scanning imaging optical system, and a mirror group. Image writing corresponding to each color signal is performed on the photosensitive drums 21Bk, 21M, 21Y, and 21C, which are image carriers provided for the respective colors of the image forming unit 18 and having a writing optical path.

  The image forming unit 18 includes photosensitive drums 21Bk, 21M, 21Y, and 21C that are image carriers for black (Bk), magenta (M), yellow (Y), and cyan (C). . As each photoconductor for each color, an OPC photoconductor is usually used. Around the photosensitive drums 21Bk, 21M, 21Y, and 21C, there are a charging device, a laser beam exposure unit from the image writing unit 17, and developing devices 20Bk, 20M, and 20Y for black, magenta, yellow, and cyan colors. 20C, primary transfer bias rollers 23Bk, 23M, 23Y, and 23C as primary transfer means, a cleaning device (not shown), a photoconductor neutralizing device (not shown), and the like. The developing devices 20Bk, 20M, 20Y, and 20C use a two-component magnetic brush developing method. The intermediate transfer belt 22, which is a belt component, is interposed between the photosensitive drums 21Bk, 21M, 21Y, and 21C and the primary transfer bias rollers 23Bk, 23M, 23Y, and 23C, and is formed on the photosensitive members. The toner images of each color are sequentially superimposed and transferred.

  On the other hand, the transfer paper P is fed from the paper feed unit 19 and then carried by the transfer conveyance belt 50, which is a belt component, via the registration roller 16. When the intermediate transfer belt 22 and the transfer conveyance belt 50 come into contact, the toner image transferred onto the intermediate transfer belt 22 is subjected to secondary transfer (collective transfer) by a secondary transfer bias roller 60 as a secondary transfer unit. Is done. As a result, a color image is formed on the transfer paper P. The transfer paper P on which the color image is formed is conveyed to the fixing device 15 by the transfer conveying belt 50, and after the image transferred by the fixing device 15 is fixed, it is discharged out of the printer main body.

  Residual toner remaining on the intermediate transfer belt 22 without being transferred during the secondary transfer is removed from the intermediate transfer belt 22 by the belt cleaning member 25. A lubricant application device 27 is disposed on the downstream side of the belt cleaning member 25. The lubricant application device 27 includes a solid lubricant and a conductive brush that rubs the intermediate transfer belt 22 to apply the solid lubricant. The conductive brush is always in contact with the intermediate transfer belt 22 and applies a solid lubricant to the intermediate transfer belt 22. The solid lubricant has an effect of improving the cleaning property of the intermediate transfer belt 22, preventing the occurrence of filming, and improving the durability.

  In an image forming apparatus, a seamless belt is used for several members. An intermediate transfer member (intermediate transfer belt) is one of important members that require electrical characteristics. The intermediate transfer belt of the present invention will be described below.

  The seamless belt of the present invention is an intermediate transfer belt type image forming apparatus, for example, a plurality of color toner development images sequentially formed on a photosensitive drum as an image carrier and sequentially superposed on the intermediate transfer belt for primary transfer. And is suitably equipped as an intermediate transfer belt in an image forming apparatus in which the primary transfer image is collectively transferred to a recording medium.

  FIG. 4 shows a layer structure of an intermediate transfer belt preferably used in the present invention. However, it is not limited to this configuration. As a configuration, a flexible elastic layer 12 is laminated on a rigid base layer 11 that can be relatively flexible, and a layer of spherical resin particles 13 is formed on the outermost surface of the elastic layer 12. .

  First, the base layer 11 will be described. Examples of the constituent material include a material containing a filler (or additive) for adjusting electric resistance in the resin, that is, a so-called electric resistance adjusting material. As such a resin, from the viewpoint of flame retardancy, for example, a fluorine-based resin such as PVDF, ETFE, a polyimide resin or a polyamide-imide resin is preferable, and particularly from the viewpoint of mechanical strength (high elasticity) and heat resistance. A polyimide resin or a polyamideimide resin is preferred.

  Examples of the electrical resistance adjusting material include a metal oxide, carbon black, an ionic conductive agent, and a conductive polymer material.

  Examples of the metal oxide include zinc oxide, tin oxide, titanium oxide, zirconium oxide, aluminum oxide, and silicon oxide. Moreover, in order to improve dispersibility, the metal oxide may be subjected to surface treatment in advance.

  Examples of carbon black include ketjen black, furnace black, acetylene black, thermal black, and gas black.

  Examples of the ionic conductive agent include tetraalkylammonium salts, trialkylbenzylammonium salts, alkylsulfonates, alkylbenzenesulfonates, alkyl sulfates, glycerol fatty acid esters, sorbitan fatty acid esters, polyoxyethylene alkylamines, polyoxyethylene fatty acids. Alcohol ester, alkyl betaine, lithium perchlorate, etc. are mentioned, and these may be used in combination.

  The electrical resistance adjusting material in the present invention is not limited to the above exemplary compounds. In addition, the coating liquid containing at least the resin component in the method for producing a seamless belt of the present invention further contains additives such as a dispersion aid, a reinforcing material, a lubricant, a heat conduction material, and an antioxidant as necessary. May be.

The electrical resistance adjusting material contained in the seamless belt suitably equipped as the intermediate transfer belt is preferably 1 × 10 ⁸ [Ω / □] to 1 × 10 ¹³ [Ω / □] in surface resistance and in volume resistance. The amount is set to 1 × 10 ⁶ [Ω · cm] to 1 × 10 ¹² [Ω · cm]. However, it is necessary to select and add an amount in a range where the molded film is brittle and does not easily break from the viewpoint of mechanical strength. is necessary.

  In other words, in the case of an intermediate transfer belt, an electrical characteristic (for example, a coating liquid in which the blending of the resin component (for example, a polyimide resin precursor or a polyamideimide resin precursor) and an electrical resistance adjusting material is appropriately adjusted is used. It is preferable to manufacture and use a seamless belt having a balance between surface resistance and volume resistance) and mechanical strength.

  In the case of carbon black, the content of the electric resistance adjusting material in the present invention is 10 [wt%] to 25 [wt%], preferably 15 [wt%] to 20 in the total solid content in the coating liquid. [Wt%]. The content in the case of a metal oxide is 1 [wt%] to 50 [wt%], preferably 10 [wt%] to 30 [wt%] of the total solid content in the coating liquid. If the content is less than the range of the respective electric resistance adjusting materials, the effect cannot be sufficiently obtained, and if the content is greater than the respective range, the mechanical strength of the intermediate transfer belt (seamless belt) decreases. This is not preferable for practical use.

Next, the elastic layer 12 laminated on the base layer 11 will be described.
As a material constituting the elastic layer 12, materials such as general-purpose resins, elastomers, and rubbers can be used, but a material having sufficient flexibility (elasticity) to sufficiently exhibit the effects of the present invention is used. It is preferable to use an elastomer material or a rubber material.

  Examples of the elastomer material include thermoplastic elastomers such as polyester, polyamide, polyether, polyurethane, polyolefin, polystyrene, polyacryl, polydiene, silicone-modified polycarbonate, and fluorine copolymer. . Examples of thermosetting include polyurethane, silicone-modified epoxy, and silicone-modified acrylic.

  Examples of the rubber material include isoprene rubber, styrene rubber, butadiene rubber, nitrile rubber, ethylene propylene rubber, butyl rubber, silicone rubber, chloroprene rubber, acrylic rubber, chlorosulfonated polyethylene, fluorine rubber, urethane rubber, and hydrin rubber. .

  A material capable of obtaining performance is appropriately selected from the various elastomers and rubbers. In particular, it is preferable to select a soft material as much as possible in order to follow the surface state of a paper such as a resack paper having irregularities in the surface properties of the paper as a transfer material.

  In the present invention, in order to form a spherical resin particle layer on the surface of this material, a thermosetting material is preferable to a thermoplastic material. The thermosetting material is excellent in adhesiveness with the resin particles due to the effect of the functional group contributing to the curing reaction, and can be reliably fixed. Vulcanized rubber is likewise preferred.

  To the selected material, a resistance adjusting agent for adjusting electrical characteristics, a flame retardant for obtaining flame retardancy, and materials such as an antioxidant, a reinforcing agent, a filler, and a vulcanization accelerator as necessary. Mixing appropriately included.

  As the resistance adjuster for adjusting the electrical characteristics, the above-mentioned various materials can be applied. However, since carbon black, metal oxide, and the like impair flexibility, it is preferable to suppress the use amount, and the ionic conductive agent and the conductive agent are used. It is also effective to use a functional polymer. Moreover, you may use these together.

The resistance value of the elastic layer 12 is 1 × 10 ⁸ [Ω / □] to 1 × 10 ¹³ [Ω / □] in terms of surface resistance, and 1 × 10 ⁶ [Ω · cm] to 1 × 10 ^{12 in} terms of volume resistance. [Ω · cm] is preferably adjusted.

  The thickness of the elastic layer 12 is preferably about 200 [μm] to 2 [mm]. If the film thickness is thin, the followability to the surface properties of the transfer medium and the effect of reducing the transfer pressure are low, such being undesirable. On the other hand, if the film thickness is too thick, the film will be heavier and will bend and become unstable, and cracks are likely to occur due to bending at the roller curvature to stretch the belt. Therefore, it is not preferable.

Next, the spherical resin particles 13 formed on the surface of the elastic layer 12 will be described.
The material is not particularly limited, and examples thereof include spherical particles mainly composed of resins such as acrylic resin, melamine resin, polyamide resin, polyester resin, silicone resin, and fluororesin. Further, the surface of particles made of these resin materials may be subjected to surface treatment with a different material. The resin particles referred to here include a rubber material. A structure in which the surface of spherical particles made of a rubber material is coated with a hard resin is also applicable. The spherical resin particles 13 may be hollow or porous.

  Of the above-described resins, silicone resin particles are most preferred as having high lubricity and high function capable of imparting releasability and abrasion resistance to the toner.

  The spherical resin particles 13 are preferably particles made of the above-described resin and formed into a spherical shape by a polymerization method or the like, and those closer to a true sphere are more preferable.

  The spherical resin particles 13 are preferably monodispersed with a volume average particle size of 0.5 [μm] to 5.0 [μm] and a sharp distribution. When the volume average particle size is 0.5 [μm] or less, the effect of transfer performance due to the particles cannot be sufficiently obtained. On the other hand, when the volume average particle size is 5.0 [μm] or more, the surface roughness becomes large. In addition, since the gap between the particles becomes large, there arises a problem that the toner cannot be transferred well or the cleaning is poor. Furthermore, since the spherical resin particles 13 are often insulative, if the volume average particle size is too large, residual charging potentials due to the spherical resin particles 13 cause image disturbance due to accumulation of potentials during continuous image output. Problems also arise.

Next, a method for attaching the spherical resin particles 13 to the elastic layer 12 will be described.
When the method of applying the spherical resin particles 13 using electrostatic force in the present invention is simply expressed, the spherical resin is developed on the same principle as that of developing the toner on the photosensitive member in the developing process in the image forming apparatus. It is characterized in that the particles 13 are applied to an intermediate transfer belt. In the present embodiment, a method similar to the two-component development method in electrophotographic development will be described as an example.

First, the spherical resin particles 13 applied on the intermediate transfer belt and magnetic particles (hereinafter referred to as carriers) for charging the spherical resin particles 13 are mixed to obtain a mixed powder (hereinafter referred to as particle coating agent). Get. It is preferable to mix so that the concentration of the spherical resin particles 13 is in the range of 5 [wt%] to 10 [wt%] with respect to the total weight of the particle coating agent, and further the concentration of the spherical resin particles 13 is 6 It is more preferable to mix so that it may become the range of [wt%]-8 [wt%]. This is because if the particle concentration is too low, a sufficient amount of spherical resin particles 13 are not applied on the intermediate transfer belt. Conversely, when the concentration of the spherical resin particles 13 is too high, the spherical resin particles 13 are scattered more than necessary, leading to deterioration of the working environment and a decrease in yield.

  Magnetic particles used as carriers include ferromagnetic metals such as iron, cobalt and nickel, metal oxides such as magnetite, magnetic materials such as ferrite, or magnetic materials such as ferrite having a resin core. Can be used. The particle diameter is preferably in the range of 20 [μm] to 60 [μm].

  The particle coating agent 30 shown in FIG. 1 is filled with this particle coating agent. In the particle coating device 30, a particle coating agent 37 in which spherical resin particles 13 and a carrier that is a magnetic particle are sufficiently mixed in a stirring portion is applied to a particle coating roller 31 that is a cylindrical particle coating agent carrier. Then, the particle application roller 31 transports the particle coating agent 37 to a region facing the intermediate transfer belt 38 to apply the spherical resin particles 13 on the surface of the intermediate transfer belt. The particle coating device 30 can be the same as the developing device generally used in the two-component magnetic brush developing system.

  As a configuration of a stirring unit that stirs and mixes the particle coating agent 37 and supplies the particle coating roller 31 to the particle coating roller 31, the particle coating agent 37 composed of the spherical resin particles 13 and the carrier is stirred and conveyed in the lateral direction or below the particle coating roller 31. Therefore, a configuration in which two first screws 33 and two second screws 34 are arranged in the horizontal direction and these members are covered with a casing 36 will be described as an example.

  In the particle coating apparatus 30 having such a configuration, a partition plate 35 is provided between the first screw 33 and the second screw 34, and the particle coating agent 37 is disposed in directions opposite to each other in the first screw 33 and the second screw 34. The particle coating agent 37 is circulated by transferring the developer at both ends in the conveyance direction without the partition plate 35.

  The first screw 33 disposed at a position farther from the particle application roller 31 than the second screw 34 replenishes the spherical resin particles 13 on the upstream side in the conveying direction, and mixes the spherical resin particles 13 and the carrier. The particle coating agent 37 is delivered to the second screw 34 disposed at a position closer to the particle coating roller 31 than the first screw 33 on the downstream side in the transport direction of the first screw 33.

  The second screw 34 conveys the particle coating agent 37 while supplying the particle coating agent to the particle coating roller 31 and collecting the particle coating agent 37 from the particle coating roller 31, and on the downstream side in the conveyance direction. The particle coating agent is delivered to the first screw 33.

  The particle application roller 31 includes a magnet roller (not shown) in which a plurality of magnetic poles are arranged, and a cylindrical sleeve rotates around the fixed magnet roller. At the part of the particle application roller 31 facing the second screw 34, it is necessary to pump up the particle application agent 37 to the particle application roller 31 and to separate the particle application agent 37 after the particle application. Is provided with a magnetic pole so as to perform its function. Carriers that are magnetic particles gather and rise to form magnetic brushes along the magnetic force lines in the normal direction with respect to the surface of the particle application roller, which are emitted from these magnetic poles.

  The particle application roller 31 and the intermediate transfer belt 38 are not directly in contact with each other in the particle application nip region, which is an area where the particle application roller 31 and the intermediate transfer belt 38 face each other, but are opposed to each other while maintaining a certain interval suitable for particle application. By applying the particle coating agent 37 on the particle coating roller 31 and bringing the particle coating agent 37 into contact with the intermediate transfer belt 38, the spherical resin particles 13 are applied on the surface of the intermediate transfer belt.

  A grounding bias power source 70 is connected to the fixed shaft 32 of the particle application roller 31. The voltage of the power source 70 connected to the fixed shaft 32 is applied to the sleeve via a conductive bearing and a conductive rotating shaft. Further, the polarity of the voltage at this time is the same as the charging polarity of the spherical resin particles 13. On the other hand, a cylindrical support (mold) 39 having conductivity that supports the back surface of the annular intermediate transfer belt 38 in contact with the surface thereof is grounded. In this way, an electric field for moving the spherical resin particles 13 separated from the carrier to the intermediate transfer belt 38 side is formed in the particle application nip region, and electrostatic is generated by the potential difference between the sleeve of the particle application roller 31 and the surface of the intermediate transfer belt. The spherical resin particles 13 are moved toward the intermediate transfer belt 38 by a force, and an amount of the spherical resin particles 13 corresponding to the magnitude of the electrostatic force (the magnitude of the electric field) due to the potential difference is transferred to the intermediate transfer belt 38. It is applied to the surface of the elastic layer 12.

  When the spherical resin particles 13 are applied to the surface of the elastic layer 12 of the intermediate transfer belt, it is preferable to supply a sufficient amount of the spherical resin particles 13. When the supply amount of the spherical resin particles 13 is small, a region where the surface of the elastic layer 12 is exposed without being covered with the spherical resin particles 13 becomes large. Therefore, not only the toner transfer property but also the remaining toner cleaning property and filming resistance are remarkably lowered.

  Specifically, with respect to the projected area ratio between the exposed portion of the elastic layer 12 and the exposed portion of the spherical resin particles 13, a sufficient amount so that the projected area ratio of the exposed portion of the spherical resin particles 13 is 60 [%] or more. The spherical resin particles 13 are preferably supplied.

  In the present embodiment, it is possible to easily adjust the particle application amount by adjusting the concentration of the particle coating agent 37 and the electric field applied during particle coating.

  Furthermore, the spherical resin particles 13 are preferably formed as a single layer in the thickness direction with respect to the elastic layer 12. As shown in FIG. 5, in the configuration including the plurality of spherical resin particles 13 in the thickness direction of the elastic layer 12, the distribution of the spherical resin particles 13 becomes uneven, and the electric resistance value of the spherical resin particles 13 is reduced. Due to the influence, the electrical characteristics of the surface of the intermediate transfer belt become non-uniform and image distortion occurs.

  Specifically, the electrical resistance value at a portion where many spherical resin particles 13 are present becomes high, and a surface potential due to residual charges is generated here, causing variations in the surface potential on the surface of the intermediate transfer belt, and adjacent to each other. Image disturbance due to a difference in image density in the portion becomes obvious.

  On the other hand, in the method of manufacturing the intermediate transfer belt proposed in the present invention, the spherical resin particles 13 are attracted and adhered to the surface of the elastic layer 12 by electrostatic force. The spherical resin particles 13 in an amount corresponding to the magnitude of the electrostatic force are adhered, and the spherical resin particles 13 can be present almost uniformly on the surface of the elastic layer, and uneven adhesion of the spherical resin particles 13 on the surface of the elastic layer. Can be reduced. Therefore, it is possible to obtain an intermediate transfer belt in which spherical resin particles 13 are arranged in the surface direction on the elastic layer surface to form a uniform uneven shape.

  Next, an example of a method for producing the intermediate transfer belt having the configuration of the present invention will be described.

First, a method for producing the base layer 11 which is a base material of the intermediate transfer belt will be described.
A method for producing the base layer 11 using the coating liquid containing at least the resin component of the present invention, that is, the coating liquid containing the polyimide resin precursor or the polyamideimide resin precursor will be described.

  The base layer 11 which is a substrate made of polyimide resin or polyamideimide resin uses a spiral coating by a nozzle or a dispenser on the surface of a cylindrical support (mold), a die coating by a wide die, or a coating roll. It can be applied by roll coating or the like. Here, roll coating will be described. Coating can be performed by an apparatus as shown in FIG. Reference numeral 40 denotes a paint pan for storing the defoamed precursor liquid which is the paint 41, reference numeral 42 denotes an application roller for continuously pumping the paint 41 from the paint pan 40, and reference numeral 43 denotes a continuous pump. A regulating roller for adjusting the thickness of the applied paint 41 with a gap with the application roller 42 to obtain a predetermined paint thickness. Reference numeral 39 denotes a paint (coating film) 41 having a predetermined thickness transferred from the application roller 42. It is a cylindrical support (mold) for making it adhere.

  First, paint 41 that is a precursor liquid sufficiently defoamed in advance is poured into the paint pan 40 into the manufacturing apparatus described above. The paint viscosity is preferably adjusted to 0.5 [Pa · s] to 10 [Pa · s] with the organic polar solvent described above. Next, the paint pan 40 in which the paint 41 is poured into the lower part of the application roller 42 is approached and immersed in the paint, and the paint 41 is applied to the surface of the application roller at a slow peripheral speed of 10 [mm / sec] to 100 [mm / sec]. Attaches and pumps upward. Thereafter, the coating thickness on the coating roller 42 is adjusted by a regulating roller 43 that is installed above the coating roller 42 and can adjust an arbitrary gap with the coating roller 42. The thickness of the paint to be regulated is preferably about twice the thickness of the paint transferred to the cylindrical support 39.

  Next, while the cylindrical support 39 is slowly rotated on the application roller 42, it is brought close to the coating thickness of the application roller 42 or less. The paint 41 on the application roller 42 is transferred onto the cylindrical support 39 that rotates in the same direction as the application roller 42 ("clockwise direction" in the direction shown in FIG. 6). A paint 41 having a predetermined film thickness is attached on the cylindrical support 39.

  After the application, the solvent in the coating film is evaporated at a temperature of about 80 [° C.] to 150 [° C.] while gradually raising the temperature while rotating the cylindrical support 39. In this process, it is preferable to efficiently circulate and remove atmospheric vapor (such as a volatilized solvent). When a self-supporting film is formed, the mold is transferred to a heating furnace (firing furnace) capable of high-temperature processing, and the temperature is raised stepwise, and finally a high temperature of about 250 [° C] to 450 [° C]. Heat treatment (firing) is performed, and the polyimide resin precursor or the polyamideimide resin precursor is sufficiently imidized or polyamideimidized to produce the base layer 11.

Then, after sufficiently cooling the base layer 11, the elastic layer 12 is subsequently laminated on the base layer 11.
The elastic layer 12 can be manufactured by coating and forming on the base layer 11 using a rubber paint in which rubber is dissolved in an organic solvent, and then drying and vulcanizing the solvent. As the coating molding method, as with the base layer 11, existing coating methods such as spiral coating, die coating, and roll coating can be applied, but the thickness of the elastic layer 12 is increased in order to improve uneven transferability. As a coating method for forming a thick film, die coating and spiral coating are excellent. Here, the spiral coating will be described. While rotating the base layer 11 in the circumferential direction and continuously supplying rubber paint with a round or wide nozzle, the nozzle is moved in the axial direction of the base layer 11 to coat the paint on the base layer 11 in a spiral shape. Work. The paint applied spirally on the base layer 11 is dried while being leveled by maintaining a predetermined rotation speed and drying temperature.

  When sufficiently leveled, the particle coating device 30 shown in FIG. 1 is installed at a position facing the intermediate transfer belt 38. On the particle application roller 31, the particle application agent 37 is raised, and the particle application agent 37 is brought into contact with the intermediate transfer belt 38 while being rotated. At this time, an electric field for moving the spherical resin particles 13 separated from the carrier to the intermediate transfer belt 38 side is formed in the particle application nip region, and the spherical resin is caused by the potential difference between the particle application roller 31 and the surface of the intermediate transfer belt 38. The particles 13 are moved toward the intermediate transfer belt 38 and the spherical resin particles 13 are applied. After applying the particles, the particles may be more firmly fixed in the elastic layer 12 by lightly pressing with a pressing member or the like as necessary. Then, after applying the particles, the elastic layer 12 is formed by curing at a predetermined temperature for a predetermined time.

  As a result, an intermediate transfer belt can be manufactured in which spherical resin particles are applied in a preferred form formed as a single layer in the thickness direction with respect to the elastic layer 12.

[Experiment]
EXAMPLES Hereinafter, the present invention will be described more specifically based on examples. However, the present invention is not limited by these examples, and these examples are appropriately modified without departing from the gist of the present invention. Is also within the scope of the present invention.

[Example 1]
A base layer coating solution was prepared as follows, and a seamless belt base layer 11 was produced using this coating solution.

<Preparation of base layer coating solution>
First, carbon black (Special Black 4; Evonik Degussa Co., Ltd.) dispersed in N-methyl-2-pyrrolidone with a bead mill in advance in a polyimide varnish (U-Varnish A; manufactured by Ube Industries) containing a polyimide resin precursor as a main component. The dispersion was prepared so that the carbon black content was 17% by weight of the polyamic acid solid content, and the mixture was thoroughly stirred to prepare a coating solution.

<Manufacture of seamless belts>
A metal cylindrical support having an outer diameter of 340 [mm] and a length of 360 [mm] roughened by blasting was used as a mold and attached to a roll coater. Next, the base layer coating liquid A is poured into the pan, the paint is pumped up at a rotation speed of 40 [mm / sec] of the coating roller, and the gap between the regulation roller and the coating roller is set to 0.6 [mm]. The thickness of the paint was controlled. Then, the rotational speed of the cylindrical support is controlled to 35 [mm / sec] and close to the application roller, and the coating on the application roller is uniformly applied on the cylindrical support with a gap of 0.4 [mm] from the application roller. After the transfer coating, the hot air circulating dryer is charged while maintaining the rotation, the temperature is gradually raised to 110 [° C.] and heated for 30 minutes, further heated to 200 [° C.] for 30 minutes, Stopped spinning. Thereafter, this was introduced into a heating furnace (firing furnace) capable of high-temperature treatment, and the temperature was raised stepwise to 320 [° C.], followed by heat treatment (firing) for 60 minutes.

<Production of elastic layer on base layer>
The respective constituent materials shown below were mixed and sufficiently kneaded using a biaxial kneader to prepare a rubber composition.

<Elastic layer material>
・ Acrylic rubber Nipol AR12 (Nippon ZEON Co., Ltd.) 100 parts by weight ・ Stearic acid Bead stearic acid Tsubaki (NOF Corporation) 1 part by weight ・ Red phosphorus Nova Excel 140F (Rin Chemical Industry Co., Ltd.) 10 parts by weight ・ Aluminum hydroxide Heidilite H42M (Showa Denko Co., Ltd.) 60 parts by weight / crosslinking agent Diak. No1 (hexamethylenediamine carbamate)
(DuPont Dow Elastomer Japan) 0.6 parts by weight / crosslinking accelerator VULCOFAC ACT55
(Salt of 70 [%] 1,8-diazabicyclo (5,4,0) undecene-7 and dibasic acid, 30 [%] amorphous silica) (Safic alca) 1 part by weight / conductive agent QAP-01 ( Tetrabutylammonium perchlorate)
(Nippon Carlit Co., Ltd.) 0.3 parts by weight

  Subsequently, the rubber composition thus obtained was dissolved in an organic solvent (MIBK: methyl isobutyl ketone) to prepare a rubber solution having a solid content of 35 [wt%]. While rotating the cylindrical support on which the prepared polyimide base layer was formed, the prepared rubber solution was moved to the support axis method while continuously discharging rubber paint from the nozzle onto the polyimide base layer. Coated. The coating amount was such that the final film thickness was 500 [μm]. When the predetermined amount was completely poured and the coating film spread evenly, the spherical resin particles 13 were applied using the particle coating device 30 of FIG.

  As spherical resin particles 13, silicone resin particles (Tospearl 130 (volume average particle size 3.0 [μm] product); Momentive Performance Materials) and ferrite magnetic carrier (saturated magnetization 60 [emu / g], particles A mixture of spherical resin particles 13 at a ratio of 7.0 [wt%] with a diameter of 50 [μm]) was used as a particle coating agent.

  After finishing the particle application, the cylindrical support coated with the rubber paint is put into a hot air circulating dryer while rotating as it is, and the temperature is raised to 90 [° C.] at a heating rate of 4 [° C./min]. For 30 minutes. Subsequently, the temperature was raised to 170 [° C.] at a heating rate of 4 [° C./min], and heat treatment was performed for 60 minutes. After stopping the heating, it was gradually cooled to room temperature. After sufficiently cooling, it was removed from the mold to obtain an intermediate transfer belt A.

[Example 2]
The intermediate transfer belt B is the same except that the spherical resin particles 13 in Example 1 are replaced with silicone resin particles (Tospearl 2000B (volume average particle size 6.0 [μm] product); Momentive Performance Materials). Obtained.

[Example 3]
The spherical resin particles 13 in Example 1 are replaced with silicone resin particles (KMP-590 (volume average particle size 2.0 [μm] product); Shin-Etsu Silicone), and the particle concentration in the particle coating agent is 4.5 [wt. %], And an intermediate transfer belt C was obtained.

[Example 4]
The spherical resin particles 13 in Example 1 are replaced with silicone resin particles (KMP-590 (volume average particle size 2.0 [μm] product); Shin-Etsu Silicone), and the particle concentration in the particle coating agent is 11.0 [wt. %], And an intermediate transfer belt D was obtained. In the particle coating step when obtaining the intermediate transfer belt D, some particle scattering was confirmed.

[Example 5]
The intermediate transfer belt E is the same except that the spherical resin particles 13 in Example 1 are replaced with acrylic resin particles (NMB-0320 (volume average particle size 3.5 [μm product]); Nippon Oil Corporation). Obtained.

[Example 6]
The intermediate transfer belt was the same except that the spherical resin particles 13 in Example 1 were replaced with melamine-silica resin particles (Opto beads 3500M (volume average particle size 3.5 [μm] product); Nissan Chemical Industries, Ltd.). F was obtained.

[Comparative Example 1]
In Example 1, as the particle application method, when the elastic layer coating is finished flowing and the coating film has spread evenly, the friction member is brought into contact with the intermediate transfer belt while rotating in the circumferential direction. The intermediate transfer belt G is manufactured in the same manner except that spherical resin particles 13 (Tospearl 130 (volume average particle size 3.0 [μm] product); Momentive Performance Materials) are applied to the nip portion of did.

[Comparative Example 2]
In Example 1, the particle coating method was the same except that the method of spraying the particle dispersion prepared by the following method was used when the coating layer was spread evenly after the elastic layer coating was poured, and the intermediate transfer A belt H was produced.

<Preparation of particle dispersion>
Disperse particles by mixing 10 parts by weight of spherical resin particles 13 (Tospearl 130 (volume average particle size 3.0 [μm] product); Momentive Performance Materials) and 90 parts by weight of methyl ethyl ketone, and then dispersing using nanomizer The liquid was adjusted.

  The following evaluations were performed on the intermediate transfer belts A to H of each of the above examples and comparative examples.

<Measurement of belt surface particle area ratio>
The surface of each belt is observed with a scanning electron microscope, and the image is binarized using image processing software (Image-plus; cyber-netics), and the projected area of the exposed portion of the elastic body and the exposed portion of the particle The rate was calculated.

  Further, the intermediate transfer belts A to H of each of the above examples and comparative examples were mounted on the image forming apparatus of FIG. 3 and the following various evaluations were performed.

<Measurement of transfer rate>
As the transfer paper, paper having a concavo-convex pattern on the surface (continuous amount 175 [kg] paper, resack paper) is used, and an operation for outputting a blue solid image is performed on this, and intermediate transfer before transfer to the paper The amount of image toner on the belt and the amount of toner remaining on the intermediate transfer belt after transfer to paper were measured, and the transfer rate was calculated from Equation 1. The transfer rate value is preferably 90% or more, and more preferably 95% or more.

<Measurement of transfer rate at the time of continuous image output of 10,000 sheets>
After continuous output of 10,000 test chart images, the test chart was stopped and the transfer rate was measured according to the above method.

<Evaluation of images when 10,000 continuous images are output>
After continuous output of 10,000 test chart images, a cyan halftone image was output on the entire surface of 175 [kg] rezac paper, and an abnormal image was observed.

  The results are shown in Table 1.

  In Examples 1 to 6, excellent performance was exhibited both at the initial stage and after output of 10,000 images. On the other hand, in Comparative Example 1, the spherical resin particles 13 were applied by pressing the friction member in a state where the rubber of the elastic layer 12 was not sufficiently cured. For this reason, the elastic layer 12 flows due to the pressing, and film thickness unevenness occurred in the completed intermediate transfer belt I. When the film thickness was measured by an eddy current film thickness meter (ISOSCOPE MP30SP; Fisher Instruments Co., Ltd.), there was a difference in film thickness of about 50 [μm] between the thickest part and the thinnest part. In addition, an image with partial density unevenness is obtained in the image after outputting 10,000 images, and the transfer rate is also inferior to those of Examples 1-6.

  Even in Comparative Example 2, there is unevenness in the particle application state, which affects image unevenness. Furthermore, some particles dropped out during the 10,000 sheet image output durability test.

  As described above, by the production method of the present invention, an intermediate transfer for realizing a high durability and high image quality image forming apparatus that can realize a high transfer rate regardless of the type and surface properties of the transfer medium and can be sustained over a long period of time. Obtaining a belt can be realized.

As described above, according to the present embodiment, the particle attaching step of attaching the spherical resin particles 13 as the particles to the surface of the elastic layer 12 formed on the base layer 11 as the base material, and the surface of the elastic layer 12 are attached. In a method of manufacturing an intermediate transfer belt, which is an intermediate transfer member used in an image forming apparatus, having a particle fixing step of fixing spherical resin particles 13 to the surface of the elastic layer 12, an electrostatic force is applied in the particle adhesion step. By attracting and attaching the spherical resin particles 13 to the surface of the elastic layer 12, it is possible to attach the spherical resin particles 13 in an amount corresponding to the magnitude of the electrostatic force at each location on the surface of the elastic layer. Thereby, the particle size resin particles 13 can be made to be present substantially uniformly on the surface of the elastic layer, and uneven adhesion of the spherical resin particles 13 on the surface of the elastic layer can be reduced. Accordingly, the variation in transfer performance due to the uneven adhesion of the spherical resin particles 13 on the surface of the elastic layer is suppressed, and the occurrence of density unevenness in the image transferred from the intermediate transfer belt to the recording medium can be suppressed. . In addition, as clarified in the above-described experiment, in order to realize a highly durable and high-quality image forming apparatus that can achieve a high transfer rate regardless of the type and surface properties of the transfer medium and can be sustained over a long period of time. The intermediate transfer belt can be obtained.
In addition, according to the present embodiment, the particle coating agent 37 is transferred to the intermediate transfer belt 38 by the particle coating roller 31 that is a rotating body that supports the particle coating agent 37 in which the spherical resin particles 13 and the carrier that is magnetic particles are mixed. By an electric field that attracts the spherical resin particles 13 from the particle application roller 31 formed in the opposite area to the intermediate transfer belt 38 side due to a potential difference between the particle application roller 31 and the intermediate transfer belt 38. Then, the spherical resin particles 13 are moved toward the intermediate transfer belt 38 from the particle application roller 31 by electrostatic force, and the spherical resin particles 13 are adhered to the surface of the elastic layer 12, thereby causing the spherical resin particles to adhere to the surface of the elastic layer. It is possible to obtain an intermediate transfer belt 38 in which the particles 13 are arranged in the plane direction to form a uniform uneven shape.
Further, according to the present embodiment, mixing is performed such that the concentration A of the spherical resin particles 13 is in the range of 5 [wt%] ≦ A ≦ 10 [wt%] with respect to the total weight of the particle coating agent 37. preferable. This is because if the particle concentration is too low, a sufficient amount of spherical resin particles 13 are not applied on the intermediate transfer belt. Conversely, if the concentration of the spherical resin particles 13 is too high, the spherical resin particles 13 are scattered more than necessary, leading to deterioration of the working environment and a decrease in yield.
Moreover, according to this embodiment, it is preferable that the volume average particle diameter of the spherical resin particles 13 is in the range of 0.5 [μm] to 5.0 [μm]. When the volume average particle diameter of the spherical resin particles 13 is 0.5 [μm] or less, the effect of transfer performance by the spherical resin particles 13 cannot be sufficiently obtained, while the volume average particle diameter is 5.0 [μm] or more. However, since the surface roughness becomes large and the gap between the spherical resin particles becomes large, there arises a problem that the toner cannot be transferred well or the cleaning is poor. Furthermore, since the spherical resin particles 13 are often insulative, if the volume average particle size is too large, residual charging potentials due to the spherical resin particles 13 cause image disturbance due to accumulation of potentials during continuous image output. Problems also arise.
Further, according to the present embodiment, it is preferable that the projected area ratio of the exposed portion of the spherical resin particles 13 in the elastic layer 12 is 60% or more. If the projected area ratio is less than 60 [%], the exposed portion of the spherical resin particle portion is too much, and the toner comes into contact with the elastic layer 12 and good transferability cannot be obtained.
In addition, according to the present embodiment, the spherical resin particles 13 are preferably silicone resin fine particles because they have lubricity and a function capable of imparting releasability and abrasion resistance to the toner.
According to the present embodiment, the elastic layer 12 is softened so that at least a part of the spherical resin particles 13 attached to the surface of the elastic layer 12 can be impregnated in the particle attaching step, and the elastic layer is used in the particle fixing step. By heating and curing 12, the spherical resin particles 13 are firmly fixed to the surface of the elastic layer 12, so that the spherical resin particles 13 are more firmly bonded than when the spherical resin particles 13 are simply pressed into the elastic layer 12 and fixed. It can be held and fixed by the elastic layer 12.
Further, according to the present embodiment, a photosensitive drum that is an image carrier that forms an electrostatic latent image on the surface, a developing device that develops the electrostatic latent image on the photosensitive drum with a developer, and a developing device. An intermediate transfer member to which the developed toner image on the photosensitive drum is transferred, and a primary transfer for transferring the toner image on the photosensitive drum onto the intermediate transfer member; and a toner image on the intermediate transfer member is recorded. In the intermediate transfer member used in the image forming apparatus for performing the secondary transfer to be transferred onto the medium, the intermediate transfer member is an intermediate transfer belt manufactured by the method for manufacturing an intermediate transfer belt of the present invention. As clarified in this experiment, an intermediate transfer belt that can achieve high transfer rate regardless of the type and surface properties of the transfer medium, and can achieve long-lasting, high-quality image formation that can be sustained over a long period of time. Can be obtained.
Further, according to the present embodiment, a photosensitive drum that is an image carrier that forms an electrostatic latent image on the surface, a developing device that develops the electrostatic latent image on the photosensitive drum with a developer, and a developing device. An intermediate transfer member to which the developed toner image on the photosensitive drum is transferred, and a primary transfer for transferring the toner image on the photosensitive drum onto the intermediate transfer member; and a toner image on the intermediate transfer member is recorded. In an image forming apparatus that performs secondary transfer to be transferred onto a medium, the intermediate transfer belt of the present invention is used as the intermediate transfer member, and as described in the above-described experiment, the type and surface of the transfer medium A high transfer rate can be realized regardless of properties, and a highly durable and high-quality image can be formed that can be sustained over a long period of time.

DESCRIPTION OF SYMBOLS 10 Printer main body 11 Base layer 12 Elastic layer 13 Spherical resin particle 15 Fixing device 16 Registration roller 17 Image writing unit 18 Image forming unit 19 Paper feeding unit 20 Developing device 21 Photosensitive drum 22 Intermediate transfer belt 23 Primary transfer bias roller 25 Belt cleaning Member 27 Lubricant coating device 30 Particle coating device 31 Particle coating roller 32 Fixed shaft 33 First screw 34 Second screw 35 Partition plate 36 Casing 37 Particle coating agent 38 Intermediate transfer belt 39 Cylindrical support (mold)
DESCRIPTION OF SYMBOLS 40 Paint pan 41 Paint 42 Application roll 43 Control roll 50 Transfer conveyance belt 60 Secondary transfer bias roller 70 Power supply 200 Photosensitive drum 201 Photoconductor cleaning device 202 Static elimination lamp 203 Charger charger 210 Belt conveyance device 230 Revolver developing unit 231 Developing device 270 Fixing device 271 Fixing roller 500 Intermediate transfer unit 501 Intermediate transfer belt 502 Toner seal member 504 Belt cleaning blade 505 Lubricant application brush 506 Lubricant 507 Primary transfer bias roller 508 Belt drive roller 509 Belt tension roller 510 Secondary transfer counter roller 511 Cleaning Opposing roller 512 Feedback current detection roller 514 Optical sensor 600 Secondary transfer unit 601 Transfer paper guide plate 05 the secondary transfer bias roller 606 transfer paper discharger 608 cleaning blade 610 a registration roller 801 primary transfer power source 802 secondary transfer power supply

Japanese Patent Laid-Open No. 7-234592

Claims (9)

An image forming apparatus comprising: a particle adhering step for adhering particles to the surface of an elastic layer formed on a substrate; and a particle adhering step for adhering particles adhering to the surface of the elastic layer to the surface of the elastic layer. In the method for producing an intermediate transfer member used for
A method for producing an intermediate transfer member, wherein the particles are attracted and adhered to the surface of the elastic layer by electrostatic force in the particle adhesion step. In the method for producing an intermediate transfer member according to claim 1,
The particle coating agent is transported to a region facing the intermediate transfer member by a rotating body carrying a particle coating agent mixed with the particles and magnetic particles on the surface, and the countering is performed by a potential difference between the rotating member and the intermediate transfer member. The elastic layer is configured to move the particles from the rotating body toward the intermediate transfer body by an electrostatic force by an electric field that attracts the particles from the rotating body formed in the region to the intermediate transfer body. A method for producing an intermediate transfer member, comprising attaching the particles to the surface of the intermediate transfer member. In the method for producing an intermediate transfer member according to claim 2,
A method for producing an intermediate transfer member, wherein the concentration A of the particles is 5 [wt%] ≦ A ≦ 10 [wt%] with respect to the total weight of the particle coating agent. In the method for producing an intermediate transfer member according to claim 1, 2, or 3,
The method for producing an intermediate transfer member, wherein the particles have a volume average particle size of 0.5 [μm] to 5.0 [μm]. In the method for producing an intermediate transfer member according to claim 1, 2, 3, or 4,
A method for producing an intermediate transfer member, wherein a projected area ratio of an exposed portion of the particles in the elastic layer is 60% or more. In the method for producing an intermediate transfer member according to claim 1, 2, 3, 4 or 5,
A method for producing an intermediate transfer member, wherein the particles are fine particles of silicone resin. In the method for producing an intermediate transfer member according to claim 1, 2, 3, 4, 5 or 6,
In the particle adhesion step, the elastic layer is softened so that at least a part of the particles adhered to the surface of the elastic layer can be impregnated, and the elastic layer is heated and cured in the particle fixing step, whereby the particles Is fixed to the surface of the elastic layer. An image carrier that forms an electrostatic latent image on the surface, a developing unit that develops the electrostatic latent image on the image carrier with a developer, and an image on the image carrier that has been developed by the developing unit is transferred. A primary transfer that transfers an image on the image carrier onto the intermediate transfer member, and a secondary transfer that transfers an image on the intermediate transfer member onto a recording medium. In the intermediate transfer member used in the image forming apparatus,
An intermediate transfer member produced by the method for producing an intermediate transfer member according to claim 1, 2, 3, 4, 5, 6 or 7. An image carrier that forms an electrostatic latent image on the surface;
Developing means for developing the electrostatic latent image on the image carrier with a developer;
An intermediate transfer member to which an image on the image carrier developed by the developing unit is transferred;
In an image forming apparatus that performs primary transfer that transfers an image on the image carrier onto the intermediate transfer member and secondary transfer that transfers an image on the intermediate transfer member onto a recording medium.
An image forming apparatus using the intermediate transfer member according to claim 8 as the intermediate transfer member.

Images