JPH02110586A - Image forming device - Google Patents
Image forming deviceInfo
- Publication number
- JPH02110586A JPH02110586A JP63262768A JP26276888A JPH02110586A JP H02110586 A JPH02110586 A JP H02110586A JP 63262768 A JP63262768 A JP 63262768A JP 26276888 A JP26276888 A JP 26276888A JP H02110586 A JPH02110586 A JP H02110586A
- Authority
- JP
- Japan
- Prior art keywords
- transfer
- transfer material
- transfer belt
- conductive
- potential
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000000463 material Substances 0.000 claims abstract description 60
- 230000005684 electric field Effects 0.000 claims description 23
- 238000001179 sorption measurement Methods 0.000 claims description 12
- 230000007613 environmental effect Effects 0.000 abstract description 5
- 239000010410 layer Substances 0.000 description 35
- 108091008695 photoreceptors Proteins 0.000 description 29
- 230000003068 static effect Effects 0.000 description 9
- 229920001971 elastomer Polymers 0.000 description 7
- 239000005060 rubber Substances 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 238000004140 cleaning Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- JOYRKODLDBILNP-UHFFFAOYSA-N Ethyl urethane Chemical compound CCOC(N)=O JOYRKODLDBILNP-UHFFFAOYSA-N 0.000 description 4
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- 229920002943 EPDM rubber Polymers 0.000 description 3
- 238000013459 approach Methods 0.000 description 3
- 230000008030 elimination Effects 0.000 description 3
- 238000003379 elimination reaction Methods 0.000 description 3
- 229920000728 polyester Polymers 0.000 description 3
- 230000007704 transition Effects 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 2
- 239000012790 adhesive layer Substances 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 230000006866 deterioration Effects 0.000 description 2
- 239000003989 dielectric material Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000000465 moulding Methods 0.000 description 2
- 229920000098 polyolefin Polymers 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 229920002379 silicone rubber Polymers 0.000 description 2
- 239000004945 silicone rubber Substances 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 229920002725 thermoplastic elastomer Polymers 0.000 description 2
- 238000011144 upstream manufacturing Methods 0.000 description 2
- WUPHOULIZUERAE-UHFFFAOYSA-N 3-(oxolan-2-yl)propanoic acid Chemical compound OC(=O)CCC1CCCO1 WUPHOULIZUERAE-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229920000049 Carbon (fiber) Polymers 0.000 description 1
- 239000004677 Nylon Substances 0.000 description 1
- 239000004696 Poly ether ether ketone Substances 0.000 description 1
- 239000004642 Polyimide Substances 0.000 description 1
- 229920000297 Rayon Polymers 0.000 description 1
- BUGBHKTXTAQXES-UHFFFAOYSA-N Selenium Chemical compound [Se] BUGBHKTXTAQXES-UHFFFAOYSA-N 0.000 description 1
- 229920006311 Urethane elastomer Polymers 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 229910021417 amorphous silicon Inorganic materials 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 229910052980 cadmium sulfide Inorganic materials 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000004917 carbon fiber Substances 0.000 description 1
- YACLQRRMGMJLJV-UHFFFAOYSA-N chloroprene Chemical compound ClC(=C)C=C YACLQRRMGMJLJV-UHFFFAOYSA-N 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- -1 fluororesin Polymers 0.000 description 1
- 230000009931 harmful effect Effects 0.000 description 1
- 229910010272 inorganic material Inorganic materials 0.000 description 1
- 239000011147 inorganic material Substances 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 1
- 150000002816 nickel compounds Chemical class 0.000 description 1
- 229920001778 nylon Polymers 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 239000004417 polycarbonate Substances 0.000 description 1
- 229920000515 polycarbonate Polymers 0.000 description 1
- 229920002530 polyetherether ketone Polymers 0.000 description 1
- 229920001721 polyimide Polymers 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 239000002964 rayon Substances 0.000 description 1
- 229910052711 selenium Inorganic materials 0.000 description 1
- 239000011669 selenium Substances 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 150000003377 silicon compounds Chemical class 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 150000003609 titanium compounds Chemical class 0.000 description 1
Landscapes
- Paper Feeding For Electrophotography (AREA)
- Electrostatic Charge, Transfer And Separation In Electrography (AREA)
Abstract
Description
【発明の詳細な説明】
（１）発明の目的
（産業上の利用分野）
この発明は静電複写機、同プリンタなど静電転写プロセ
スを利用する画像形成装置に関するものである。DETAILED DESCRIPTION OF THE INVENTION (1) Object of the Invention (Field of Industrial Application) The present invention relates to an image forming apparatus using an electrostatic transfer process, such as an electrostatic copying machine and a printer thereof.
（従来技術と解決すべき課題）
走行する転写ベルト、転写ドラムなどの表面誘電体層に
転写材を静電的に吸着搬送して、像担持体の存する転写
部位に持ち来たし、転写ベルトなどからの電界によって
像担持体に形成したトナー像を転写材に転移させるよう
に構成した画像形成装置が、たとえばＵＳＰ２５７６８
８２号明細書、同３２４４０８３号明細書などにみるよ
うにすでに提案されている。(Prior art and issues to be solved) The transfer material is electrostatically adsorbed and conveyed to the surface dielectric layer of a moving transfer belt, transfer drum, etc., and brought to the transfer site where the image bearing member is located, and transferred from the transfer belt, etc. An image forming apparatus configured to transfer a toner image formed on an image carrier to a transfer material by an electric field is disclosed in US Patent No. 25768, for example.
It has already been proposed as seen in Specifications No. 82 and No. 3244083.
この種の装置では、絶縁性の転写ベルトの裏面からコロ
ナ放電器による放電によって転写電界を発生させてトナ
ー像を転写するように構成するとともに、この転写帯電
に先立って転写材を転写ベルトに静電吸着させるための
コロナ放電器を具備している。This type of device is configured to transfer a toner image by generating a transfer electric field by discharging from a corona discharger from the back side of an insulating transfer belt, and prior to this transfer charging, the transfer material is statically placed on the transfer belt. It is equipped with a corona discharger for electrostatic adsorption.
上記の装置のように、誘電体層の表面に転写材を静電吸
着させて、静電転写を行なうような装置は、転写後像担
持体から転写材を分離するさい、その後、転写ベルトか
ら転写材分離するさいの剥離放電によって、誘電体の表
面に転写電界とは逆極性の電荷が蓄積されて、転写材の
吸着不良、転写不良が発生することがあった。In a device that performs electrostatic transfer by electrostatically adhering the transfer material to the surface of the dielectric layer, such as the above device, when separating the transfer material from the image carrier after transfer, the transfer material is removed from the transfer belt. Due to peeling discharge when the transfer material is separated, charge having a polarity opposite to that of the transfer electric field is accumulated on the surface of the dielectric, which may cause poor adsorption of the transfer material and poor transfer.
このような事態を回避するため、たとえば特公昭６１−
４０９９０号公報などに開示されているように、誘電体
表面に交流コロナ帯電を行なって誘電体表面の電位を安
定させる、また、多色複写など多重転写系において誘電
体の表裏から交流コロナ帯電または互に異極性の直流コ
ロナ放電を行なって表面電位の安定をはかるものが知ら
れている。In order to avoid such a situation, for example,
As disclosed in Japanese Patent No. 40990, AC corona charging is applied to the dielectric surface to stabilize the potential of the dielectric surface, and AC corona charging or A device is known that stabilizes the surface potential by performing direct current corona discharges of different polarities.
しかしながら、このようなものは、コロナ放電によって
多量のコロナ生成物、とくにオゾンが発生して誘電体表
面を劣化させ、像担持体にも悪影響を及ぼすばかりでな
く、誘電体へのコロナ放電は電位安定性が悪く、とくに
転写ベルトなどが誘電体のみの場合は、基準電位面を有
しないので極めて不安定で環境依存性が高い。However, in this type of material, a large amount of corona products, especially ozone, is generated by corona discharge, which not only deteriorates the dielectric surface and has a negative effect on the image carrier, but also corona discharge to the dielectric material The stability is poor, especially when the transfer belt is made of only a dielectric material, since it does not have a reference potential surface, it is extremely unstable and highly dependent on the environment.
また、このようなコロナ放電による弊害を防止するため
に、たとえば、特開昭５６−１５４７７２号公報には、
転写材と接触する転写ベルト表面を１０”００１１以上
の絶縁層に形成し、裏面を１０”Ωｃｍ以下の導電層と
して、この導電層をアースし、絶縁層を接触帯電させる
技術が開示されている。In addition, in order to prevent the harmful effects caused by such corona discharge, for example, Japanese Patent Application Laid-open No. 154772/1983 discloses
A technique has been disclosed in which an insulating layer of 10"0011 or more is formed on the surface of the transfer belt that comes into contact with the transfer material, a conductive layer of 10" Ωcm or less is formed on the back surface, this conductive layer is grounded, and the insulating layer is charged by contact. .
このものは、導電層が基準等電位面の作用をなし、接触
帯電を行なっているために誘電体表面の電位安定性には
すぐれている。This device has excellent potential stability on the dielectric surface because the conductive layer functions as a reference equipotential surface and performs contact charging.
しかしながら、この場合、接触帯電の電界強度が高いの
で、絶縁層にピンホールなどの欠陥があると高圧がリー
クし、たとえば、帯電手段として導電性ブラシを用いた
場合、その面積にわたって帯電不足による転写不良が生
ずる。However, in this case, the electric field strength of contact charging is high, so if there is a defect such as a pinhole in the insulating layer, high voltage will leak.For example, if a conductive brush is used as the charging means, transfer due to insufficient charging over the area. Defects occur.
とくに、上述のような転写ベルトの場合、絶縁層は薄い
方が転写効率がよく、該層の厚みは１００ｇｍ以下が好
ましいが、このような薄層では、ピンホールのないもの
を製造することは極めて困難であり、また、上述のよう
な構成では表面帯電のみで転写電界を形成しているので
、高温高湿環境下で、転写材が低抵抗化しているような
場合には、転写ベルト表面の電荷のリークによる転写不
良、吸着不良を発生しやすい。In particular, in the case of the above-mentioned transfer belt, the thinner the insulating layer, the better the transfer efficiency, and the thickness of the layer is preferably 100 gm or less, but with such a thin layer, it is difficult to manufacture one without pinholes. In addition, in the configuration described above, the transfer electric field is formed only by surface charging, so if the transfer material has low resistance in a high temperature and high humidity environment, the transfer belt surface transfer and suction defects are likely to occur due to charge leakage.
さらに上述のようなものは、転写ベルト表面の電界が均
一であるため、像担持体と転写ベルトが当接する以前の
位置においても、像担持体表面のトナーを転写ベルトに
吸引する作用が働いてトナーが転写ベルトの方向に飛翔
してしまい、忠実な転写が行なわれず、文字まわりにト
ナー粉が散っている、所謂“とびちり°゛現象発生して
画質の劣化を招来する。これを防止すべく電界強度を弱
めると、線状の画像の周辺部分のみが転写される゛中抜
けパ現象が発生する。Furthermore, in the above-mentioned device, since the electric field on the surface of the transfer belt is uniform, the toner on the surface of the image carrier is attracted to the transfer belt even before the image carrier and the transfer belt come into contact. The toner flies in the direction of the transfer belt, preventing faithful transfer, and causing toner powder to scatter around the characters, a so-called "splatter" phenomenon, which causes deterioration in image quality.To prevent this, When the electric field strength is weakened, a hollow pattern phenomenon occurs in which only the peripheral portion of a linear image is transferred.
本発明は、このような事態に対処すべくなされたもので
あって、転写材を吸着搬送する手段をそなえ、該手段か
らの電界によって転写を行なうような画像形成装置にお
いて、環境依存性が小さく、転写材を安定して確実に搬
送し得るとともに高い転写効率で忠実な転写を可能とす
る装置を提供することを目的とするものである。The present invention has been made to deal with such a situation, and is an image forming apparatus that is equipped with a means for attracting and conveying a transfer material and performs transfer using an electric field from the means, which has less environmental dependence. It is an object of the present invention to provide a device that can transport a transfer material stably and reliably, and that can perform faithful transfer with high transfer efficiency.
（２）発明の構成
（課題を解決する技術手段、その作用）上記の目的を達
成するため１本発明は、像担持体と、これに当接して転
写部位を形成するとともに転写材をこの位置に吸着、搬
送する転写材吸着搬送手段とをそなえ、該転写材吸着搬
送手段の転写材と当接する面と反対側に、像担持体のト
ナー像を転写材に移動させる方向に電界を発生させる電
界発生手段を配設した画像形成装置において。(2) Structure of the invention (technical means for solving the problem, its operation) In order to achieve the above objects, the present invention includes an image bearing member, a transfer region in contact with the image carrier, and a transfer material at this position. A transfer material adsorption/conveying means for adsorbing and conveying the transfer material is provided, and an electric field is generated on the opposite side of the surface of the transfer material adsorption/conveyance means that comes into contact with the transfer material in the direction of moving the toner image on the image carrier to the transfer material. In an image forming apparatus equipped with an electric field generating means.
前記転写材吸着搬送手段の、前記像担持体に当接する側
に体積抵抗が１０’Ωｃｍ以上の絶縁層を、その反対側
に体積抵抗が１０”ΩＣ１以下の高抵抗層を形成してな
ることを特徴とするものである。An insulating layer having a volume resistivity of 10'Ωcm or more is formed on the side of the transfer material adsorption/conveying means that comes into contact with the image carrier, and a high resistance layer having a volume resistivity of 10'ΩC1 or less is formed on the opposite side. It is characterized by:
このように構成することによって、転写ベルトなどの転
写材吸着搬送手段の表面電位を所望の電位勾配となるよ
うに調整して、トナーのとびちりや中抜けがなく、高転
写率で忠実な転写が実行できるとともに、転写材吸着搬
送手段、これに付帯する電源などコストダウンにも有効
で耐久性の大きい装置を得ることが可能となった。With this configuration, the surface potential of the transfer material adsorption/conveying means such as the transfer belt can be adjusted to the desired potential gradient, and faithful transfer can be achieved at a high transfer rate without toner scattering or hollow spots. It has become possible to obtain a highly durable device that is not only executable, but also effective in reducing costs such as the transfer material suction and conveyance means and the accompanying power source.
（実施例の説明）
第１図は本発明の実施例たる画像形成装置の構成を示す
側面図であって、導電性駆動ローラ４と１導電性ローラ
８との間に転写ベルト３が懸架してあり、該転写ベルト
３に、表面に周知の手段によって形成されたトナー像Ｔ
を担持し１図示矢印Ａ方向に回転する感光体ｌが当接し
て両者が同期走行するものとする。(Description of Embodiments) FIG. 1 is a side view showing the configuration of an image forming apparatus according to an embodiment of the present invention, in which a transfer belt 3 is suspended between a conductive drive roller 4 and a conductive roller 8. A toner image T is formed on the surface of the transfer belt 3 by a known means.
It is assumed that a photoreceptor 1 carrying a photoreceptor 1 and rotating in the direction of arrow A in the figure comes into contact with the photoreceptor 1 and the two move in synchronization.
図示右方から供給される転写材Ｐは、後述するように転
写ベルト３に静電的に吸着されてこれとともに走行し、
感光体ｌと転写ベルド３とが当接する転写部位において
、転写ベルトからの電界によって感光体のトナー像が転
写材に転写される。The transfer material P supplied from the right side in the figure is electrostatically attracted to the transfer belt 3 and travels with it, as will be described later.
At a transfer site where the photoreceptor 1 and the transfer belt 3 come into contact, the toner image on the photoreceptor is transferred onto the transfer material by an electric field from the transfer belt.
転写後、転写材は感光体ｌから分離して転写ベルト３と
ともに図示左方に搬送され、駆動ローラ４の位置におい
て転写ベルト３から曲率分離されて、さらに不図示の定
着部位に搬送される。After the transfer, the transfer material is separated from the photoreceptor 1 and conveyed to the left in the figure together with the transfer belt 3, separated by curvature from the transfer belt 3 at the position of the drive roller 4, and further conveyed to a fixing site (not shown).
転写材を解放した転写ベルト３は、クリーニングブレー
ド７によってクリーニングされて次の工程にそなえるこ
とになる。The transfer belt 3 from which the transfer material has been released is cleaned by the cleaning blade 7 and is ready for the next process.
図示の実施例装置についてさらに具体的に説明すると、
感光体としては有機光導電体（ｏｐｃ）を用いており（
セレン、アモルファスシリコン、硫化カドミウムなど無
機半導体をも利用できることは云う迄もない）、潜像形
成手段としては画像変調されたレーザビームを用いるも
のとする。More specifically, the illustrated embodiment device will be described as follows.
An organic photoconductor (OPC) is used as the photoreceptor (
It goes without saying that inorganic semiconductors such as selenium, amorphous silicon, and cadmium sulfide can also be used.) An image-modulated laser beam is used as the latent image forming means.
現像方式は負帯電トナーなレーザ光照射部分に付着させ
る、イメージ露光による反転現像を行なうものとする。The development method is to perform reversal development by image exposure, in which negatively charged toner is attached to the laser beam irradiated area.
転写ベルト３は、第２図にその断面を示すように、感光
体１に近い側から、絶縁層３１、接着層３２および高抵
抗層３３の３層構成となっており、高抵抗層３３の裏面
に電源６から導電性の給電ブラシ２を介してバイアス電
圧が印加される。As shown in the cross section of FIG. 2, the transfer belt 3 has a three-layer structure consisting of an insulating layer 31, an adhesive layer 32, and a high-resistance layer 33 from the side closer to the photoreceptor 1. A bias voltage is applied to the back surface from a power source 6 via a conductive power supply brush 2 .
転写ベルト３の絶縁層３１は体積抵抗が１０”Ωｃｍ以
上で、厚みを２０〜１５０ｘ■とじ、接着層３２は厚み
をｌＯ〜５０ＩＬｍの範囲内とし、高抵抗層３３は体積
抵抗が１０ＨΩｃ１１以下で厚みは５０〜３００μ■の
範囲に設定する。The insulating layer 31 of the transfer belt 3 has a volume resistivity of 10"Ωcm or more and a thickness of 20 to 150x2, the adhesive layer 32 has a thickness of 10 to 50ILm, and the high resistance layer 33 has a volume resistivity of 10HΩc11 or less. The thickness is set in the range of 50 to 300 μm.
材質は、絶縁層３１はポリエステル、フッ素樹脂、ポリ
イミド、ポリエーテルエーテルケトン、ポリカーボネー
トなど高い絶縁性を有する材料を押出し成型、遠心分離
成型などによってチューブ状に成型することが可能であ
って表面の平滑性のすぐれたものを用いる。As for the material, the insulating layer 31 can be formed into a tube shape by extrusion molding, centrifugal molding, etc. of a material with high insulation properties such as polyester, fluororesin, polyimide, polyether ether ketone, polycarbonate, etc., and has a smooth surface. Use materials with excellent quality.
また、ポリエステル系、ポリオレフィン系などの熱可塑
性エラストマーを利用することも可能である。It is also possible to use thermoplastic elastomers such as polyester and polyolefin.
高抵抗層３３は、ポリエステル系、ポリオレフィン系、
ウレタン系などの熱可塑性エラストマーに、チタン化合
物、ニッケル化合物、シリコン化合物あるいはこれら化
合物をウィスカー状にした半導電性無機物質を分散させ
て高抵抗化し、絶縁層と同様に成型して構成する。The high resistance layer 33 is polyester-based, polyolefin-based,
It is constructed by dispersing titanium compounds, nickel compounds, silicon compounds, or semiconductive inorganic substances in the form of whiskers of these compounds into a thermoplastic elastomer such as urethane to increase the resistance, and molding it in the same way as the insulating layer.
また、ウレタン、シリコン、ＥＰＤＭ、クロロブレンな
どのゴム材を所望の抵抗値に調整したものを用いてもよ
い、このときの高抵抗層の厚みはＯ９１〜１．０ｍｍの
範囲とする。Further, a rubber material such as urethane, silicone, EPDM, or chlorobrene adjusted to a desired resistance value may be used. In this case, the thickness of the high resistance layer is in the range of 091 to 1.0 mm.
非画像領域または画像形成時以外の回転時に転写ベルト
に付着するトナーは、前述のように、クリーニングブレ
ード７によってかき落すが、該ブレードはウレタンゴム
、シリコンゴムなどで、硬度５０〜９０°（ＪＩＳＡ硬
度）のものが好適で、転写材Ｐを挿入する位置を基準と
して、除電用の導電性ブラシ５の上流側に配置するもの
とし１反対側には図示のローラ４、あるいは相当の硬度
を有する板材などバックアップ部材を配設しておくこと
が必要である。Toner that adheres to the transfer belt in non-image areas or during rotation other than during image formation is scraped off by the cleaning blade 7, as described above, and the blade is made of urethane rubber, silicone rubber, etc. It is preferable to have a roller 4 having a hardness (hardness), and it shall be placed on the upstream side of the conductive brush 5 for static elimination with reference to the position where the transfer material P is inserted. It is necessary to provide backup members such as plates.
前記給電ブラシ２および導電性ブラシ５は、ステンレス
、カーボン繊維などを束ねてアルミ板で挟持した構成と
し、その体積抵抗はｔｏｅΩｃｍ以下とする。また、給
電ブラシ２、導電ブラシ５としては、レーヨン、ナイロ
ンなどの繊維にカーボンを混入して抵抗を適価にｙＪａ
ｌたものを用いることができる。さらに、ブラシの代り
に、導電性ローラ、導電性ゴムブレードなどを利用する
ことも可能である。The power supply brush 2 and the conductive brush 5 are constructed by bundling stainless steel, carbon fiber, or the like and sandwiching the bundle between aluminum plates, and have a volume resistivity of toeΩcm or less. In addition, as the power supply brush 2 and the conductive brush 5, carbon is mixed into fibers such as rayon or nylon, and the resistance is appropriately adjusted.
1 can be used. Furthermore, instead of a brush, it is also possible to use a conductive roller, a conductive rubber blade, or the like.
図示のように導電ブラシ５はアースされているので、同
様にアースしである導電性ローラ８と対向配置すること
によって、転写ベルト３の表面電荷を充分に除去できる
ことができる。As shown in the figure, the conductive brush 5 is grounded, so by arranging it opposite the conductive roller 8, which is also grounded, the surface charge on the transfer belt 3 can be sufficiently removed.
以上のような構成により、転写ベルト３の高抵抗層３１
に、給電ブラシ２をとおして＋５００〜＋３０００Ｖ、
好マシくは、＋１０００〜＋２０００ｖのバイアスを印
加して、転写材の吸着搬送を確保したうえ、７５％以上
の良好な転写効率を得ることができた。With the above configuration, the high resistance layer 31 of the transfer belt 3
, +500 to +3000V through the power supply brush 2,
Preferably, by applying a bias of +1000 to +2000 V, it was possible to ensure suction and conveyance of the transfer material and to obtain a good transfer efficiency of 75% or more.
この場合、導電ブラシ５には、ピーク間電圧５００〜１
５００ｖ、周波数１００〜２０００Ｈｚの交流バイアス
、または給電ブラシ２と同極性のバイアス電圧（直流３
００〜１００ＯＶ）を印加することによって有効に転写
ベルトの除電を行なうことができる。In this case, the conductive brush 5 has a peak-to-peak voltage of 500 to 1
500V, AC bias with a frequency of 100 to 2000Hz, or a bias voltage of the same polarity as the power supply brush 2 (DC 3
00 to 100 OV), the charge on the transfer belt can be effectively eliminated.
第３Ａ図は、第１図々示の装置の転写ベルトの表面を、
第３Ｂ図に示すようにＩ、ＩＩ、Ｈに区分し、これに基
ずいて表面電位の推移を示すものである。FIG. 3A shows the surface of the transfer belt of the apparatus shown in FIG.
As shown in FIG. 3B, the surface potential is divided into I, II, and H, and the transition of the surface potential is shown based on these classifications.
なお、ここでは簡単のために転写材が存在しない場合に
について説明するが、転写材が存在する場合も、電位が
若干シフトするだけで基本的な電位の傾向、したがって
作用に変化はない。Note that, for simplicity, the case where no transfer material is present will be described here, but even if a transfer material is present, there is no change in the basic tendency of the potential, and hence the effect, although the potential is only slightly shifted.
導電性ローラ８と導２電ブラシ５とが対向する部分工で
は転写ベルトの表面電位はほぼＯＶかないしは若干負極
性にシフトする。In partial machining where the conductive roller 8 and the conductive brush 5 face each other, the surface potential of the transfer belt is approximately OV or slightly shifted to negative polarity.
転写ベルト３が導電性ローラ８を離れて感光体１に当接
する位置に接近すると（第３Ａ図の工と■の間）、給電
ブラシ２から注入された電荷が転写ベルト３の高抵抗層
３１内で移動して１図示Ｉ〜ＩＩの間に示すような電位
勾配が発生する。When the transfer belt 3 leaves the conductive roller 8 and approaches the position where it comes into contact with the photoreceptor 1 (between mark and black in FIG. 3A), the charge injected from the power supply brush 2 is applied to the high-resistance layer 31 of the transfer belt 3. A potential gradient as shown between I and II in FIG. 1 is generated.
このような電位勾配によって、転写ベルトに供給された
転写材は該ベルトに確実に保持、搬送されるとともに、
感光体ｌから遠い位置では電界が弱いので、前述のよう
なトナーの゛とびちり゛現象の発生を阻止することがで
きる。Due to such a potential gradient, the transfer material supplied to the transfer belt is reliably held and conveyed by the belt, and
Since the electric field is weak at a position far from the photoreceptor 1, it is possible to prevent the toner scattering phenomenon described above from occurring.
転写ベルト３と感光体ｌの当接点に近ずくにしたがって
該ベルトの表面電位は上昇し、転写材が感光体に充分密
着したところ（図示ＩＩの位置）で転写が行なわれる。The surface potential of the belt increases as it approaches the contact point between the transfer belt 3 and the photoreceptor 1, and transfer is performed when the transfer material comes into sufficient contact with the photoreceptor (position II in the figure).
転写ベルトの表面電位はさらに上昇して、給電ブラシの
位置で、図示符号ａ゛に至る筈であるが、転写後、転写
材が感光体から分離するときに発生する剥離放電によっ
て、転写ベルトには転写電位とは逆極性の電荷が蓄精さ
れるので符号ａにとどまる。The surface potential of the transfer belt should further increase and reach the symbol a'' at the position of the power supply brush, but after the transfer, the transfer belt is affected by peeling discharge that occurs when the transfer material separates from the photoreceptor. remains at sign a because charges of opposite polarity to the transfer potential are accumulated.
上記ピーク電位位置から、アースされた導電性駆動ロー
ラ４に向う間において、図示のように電位が低下する方
向の電位勾配が発生するが、このとき、転写ベルトが該
導電性駆動ローラに接触する部分において該ベルトの電
位が充分ＯＶに近ずくように転写ベルト３の高抵抗層の
抵抗を設定しておくものとする。From the peak potential position to the grounded conductive drive roller 4, a potential gradient occurs in the direction in which the potential decreases as shown in the figure, and at this time, the transfer belt comes into contact with the conductive drive roller. The resistance of the high-resistance layer of the transfer belt 3 is set so that the potential of the belt is sufficiently close to OV at some portions.
このように構成することによって、分離位置における転
写材に対する転写ベルトの吸着作用は小さくなり、容易
に該ベルトから分離することができる。With this configuration, the adsorption effect of the transfer belt on the transfer material at the separation position is reduced, and the transfer material can be easily separated from the belt.
第３Ａ図、第３Ｂ図における区域■においては、転写ベ
ルト表面に蓄積された負の電荷のために負電位が表れ、
両ローラ４．８はいずれもアースされて電位差がないの
で、導電ブラシによって除電されるまでは一定電位に維
持される。In the area ■ in FIGS. 3A and 3B, a negative potential appears due to the negative charges accumulated on the transfer belt surface.
Since both rollers 4.8 are both grounded and there is no potential difference, they are maintained at a constant potential until static electricity is removed by the conductive brush.
以上のような作用が円滑に実行されるには、転写ベルト
の高抵抗層内での電荷の移動が迅速かつ適度に行なわれ
る必要があり、このため、高抵抗層の体積抵抗は、１０
６〜１０′Ωｃｍ、より好適には１０”〜１ＯＩ２Ωｃ
ｍの範囲内にあることが望ましい。In order for the above-mentioned actions to be carried out smoothly, it is necessary for the charge to move quickly and appropriately within the high resistance layer of the transfer belt, and for this reason, the volume resistivity of the high resistance layer is 10.
6-10'Ωcm, more preferably 10''-1OI2Ωc
It is desirable that it be within the range of m.
また、転写ベルトの絶縁層は、強いクーロン力を働かせ
るために電荷の移動は小さいことが望ましいので、その
抵抗はｌＯＩ′ＩΩｃｍ以上、好ましくは１０１１０ｃ
ｍ以上とするのが好適である。Furthermore, in order to exert a strong Coulomb force, the transfer belt's insulating layer desirably has a small charge transfer, so its resistance is 1OI'IΩcm or more, preferably 10110c.
It is preferable to set it to m or more.
このように設定することによって、適度の電位勾配、転
写に必要な転写電位が得られ、トナーの“とびちり”が
なく、転写材が確実に転写ベルトに保持、搬送される。By setting in this way, an appropriate potential gradient and transfer potential necessary for transfer can be obtained, and the transfer material can be reliably held and conveyed by the transfer belt without toner "flickering".
また、給電ブラシのような簡単な手段によって、しかも
、０．５〜３Ｋｖ（実際には２Ｋｖを印加した）程度の
、公知のコロナ放電器の場合に要するバイアス電圧、４
．０〜８．ＯＫｖに比してはるかに低い電圧ですみ、電
源コストも低くてすみ、感光体に対する悪影響も少ない
。Furthermore, the bias voltage required in the case of a known corona discharger of about 0.5 to 3 Kv (actually 2 Kv was applied) by a simple means such as a power supply brush,
．． 0-8. The voltage required is much lower than OKv, the power supply cost is low, and there is little adverse effect on the photoreceptor.
さらにまた、転写ベルトの表面電位安定性についても、
表面に接触型の導電ブラシ５を配設し。Furthermore, regarding the surface potential stability of the transfer belt,
A contact type conductive brush 5 is arranged on the surface.
裏面の高抵抗層を上述のような値とすることによって環
境安定性、耐久性にすぐれ、さらに高抵抗層の抵抗を半
導電性の無機材料によって制御することによってとくに
環境安定性の向上は顕著なものがある。By setting the high-resistance layer on the back side to the above-mentioned values, it has excellent environmental stability and durability, and by controlling the resistance of the high-resistance layer with a semiconductive inorganic material, the environmental stability is particularly improved. There is something.
第４図は本発明の他の実施例を示すものであって、感光
体１、転写ベルト３、これを懸架するローラ４．８など
前記実施例のものと対応する部分には同一の符号を付し
て示してあり、それらについての説明は必要ない限り省
略する（後述の実施例においても同様とする）。FIG. 4 shows another embodiment of the present invention, in which parts corresponding to those in the previous embodiment, such as the photoreceptor 1, the transfer belt 3, and the roller 4.8 that suspends it, are given the same reference numerals. The explanation thereof will be omitted unless necessary (the same applies to the embodiments described later).
この実施例においては、感光体ｌが転写ベルト３を介し
て導電性弾性ローラ８に当接する位置に配設してあり、
また、転写ベルト３の高抵抗層へ電圧を印加する手段と
して導電性ローラ２ａを使用しており、これがばね２ｂ
によって転写ベルトに圧接しており、これによって感光
体ｌと転写ベルト３とが圧接して転写部位を形成するニ
ップ部を調整できるようになっている。In this embodiment, the photoreceptor l is arranged at a position where it comes into contact with the conductive elastic roller 8 via the transfer belt 3,
Further, a conductive roller 2a is used as a means for applying voltage to the high resistance layer of the transfer belt 3, and this
This makes it possible to adjust the nip portion where the photoreceptor 1 and the transfer belt 3 come into pressure contact to form a transfer site.
転写ベルト３の表面絶縁層の除電を行なう導電ブラシ５
には電源９によって交流電圧を印加している。A conductive brush 5 that removes static electricity from the surface insulating layer of the transfer belt 3
An alternating current voltage is applied by a power source 9 to.
第５Ａ図、第５Ｂ図はこの装置における転写ベルトの表
面電位の推移を、前述の実施例と同様の条件で示したも
のである。FIGS. 5A and 5B show the transition of the surface potential of the transfer belt in this apparatus under the same conditions as in the previous embodiment.
第５Ｂ図の■の部分ではベルト３の表面は除電されてい
るので、第５Ａ図に示すように、はぼＯＶである。印加
電圧はピーク間電圧１２００Ｖ、周波数８００Ｈｚの交
流電圧としたが、この値はピーク間電圧５００〜２００
０Ｖ、周波数１００〜２０００Ｈｚの範囲内で良好な除
電作用が得られる。In the part marked ■ in FIG. 5B, the surface of the belt 3 has been neutralized, so as shown in FIG. 5A, it is OV. The applied voltage was an AC voltage with a peak-to-peak voltage of 1200 V and a frequency of 800 Hz;
A good static elimination effect can be obtained within the range of 0 V and frequency of 100 to 2000 Hz.
また、このように交流電圧を印加した場合、転写ベルト
の絶縁層にピンホールがあっても、該ベルトの高抵抗層
を１０＠〜１０１４Ωｃｍの範囲内に設定することによ
って、リーク電流を十分に抑制可能で電源出力が低下す
るようなことがない。In addition, when applying an AC voltage in this way, even if there are pinholes in the insulating layer of the transfer belt, leakage current can be sufficiently suppressed by setting the high resistance layer of the belt within the range of 10@~1014 Ωcm. This can be suppressed and the power output will not decrease.
第５Ａ図の！■の部分では、この実施例においては、感
光体１が導電性弾性ローラ８に圧接する関係となってい
るので、感光体ｌと転写ベルト３との充分な密着が確保
され、それ以前の電位が確実にＯｖに維持され、密着後
、第５Ｂ図に示すように表面電位が上昇し、導電ローラ
２ａの位置でピークに達する。Figure 5A! In the part (2), in this embodiment, the photoreceptor 1 is in pressure contact with the conductive elastic roller 8, so sufficient adhesion between the photoreceptor 1 and the transfer belt 3 is ensured, and the previous potential is is reliably maintained at Ov, and after close contact, the surface potential increases as shown in FIG. 5B and reaches a peak at the position of the conductive roller 2a.
第５Ｂ図の符号＆、 ＆”は前述の実施例における電
位推移の場合と変りはない。また、第５Ｂ図ｍ、■部分
における電位変化も前述の実施例のものと同様の傾向で
変化する。The symbols “&” and “&” in FIG. 5B are the same as in the case of the potential transition in the previous embodiment. Also, the potential changes in the portions m and ■ in FIG. 5B change with the same tendency as in the previous embodiment. .
この装置は前述のように、感光体と転写ベルトとの密着
性がよいので、導電性ローラ２ａに３ＫＶと比較的高電
圧を印加することによって中抜けを防止することができ
る。As described above, this device has good adhesion between the photoreceptor and the transfer belt, so it is possible to prevent hollow spots by applying a relatively high voltage of 3 KV to the conductive roller 2a.
また、転写部位以前の位置には転写方向の電界が存在せ
ず、転写電位に達する部分の勾配が急であるので、感光
体と転写材の密着性の良さと相まってトナー像の忠実な
転写が可能である。In addition, there is no electric field in the transfer direction at the position before the transfer site, and the slope at the part where the transfer potential is reached is steep, which, combined with the good adhesion between the photoreceptor and the transfer material, ensures faithful transfer of the toner image. It is possible.
この実施例装置における導電性弾性ローラ８としては、
硬度が２０〜５０°（ＪＩＳ Ａ硬度）のＥＰＤＭ、
ＣＲ，ＮＢＲ、シリコンゴムなどの導電性ゴム、硬度が
１５〜４０’ （アスカ−Ｃ硬度）のウレタン、シリコ
ンの導電性スポンジで抵抗を１０’ΩＣ１以下に調整し
たものを用いることができ、本発明の目的からはスポン
ジを用いるのが好適である。The conductive elastic roller 8 in this embodiment device is as follows:
EPDM with a hardness of 20 to 50° (JIS A hardness),
Conductive rubbers such as CR, NBR, and silicone rubber, urethane with a hardness of 15 to 40' (Asker-C hardness), and silicone conductive sponges with resistance adjusted to 10'ΩC1 or less can be used. For the purposes of the invention, it is preferred to use a sponge.
転写バイアスを印加するための導電性ローラ２ａとして
は、アルミニューム、ステンレス、鉄などの金属からな
るローラまたはこれに抵抗が１０６ΩＣ層以下の導電性
ゴムを被覆したものを用いることができる。As the conductive roller 2a for applying the transfer bias, a roller made of metal such as aluminum, stainless steel, or iron, or a roller coated with a conductive rubber having a resistance of 10<6 >ΩC or less can be used.
前述のように、ローラ２ａはバネ２ｂによって転写ベル
ト３の方向に押圧されていて、感光体１と転写ベルト３
との圧接ニップ部の長さ（転写材の走行方向にみた）、
圧力を調整できるので、転写効率の向上、中抜けの防止
に好適である。As mentioned above, the roller 2a is pressed in the direction of the transfer belt 3 by the spring 2b, and the photoreceptor 1 and the transfer belt 3
The length of the pressure nip (as seen in the direction of transfer material travel),
Since the pressure can be adjusted, it is suitable for improving transfer efficiency and preventing hollow spots.
第６図は本発明のさらに他の実施例を示すもので、この
装置においては、除電手段として導電ブラシを使用せず
、クリーニングブレード７を導電性ゴムとしてこれに交
流電圧（またはこれに転写と同極性の直流を重畳したも
の）を印加するように構成しである。FIG. 6 shows still another embodiment of the present invention. In this device, a conductive brush is not used as the static eliminating means, and the cleaning blade 7 is made of conductive rubber, and an alternating voltage (or a transfer voltage is applied to it) is applied to the cleaning blade 7. It is configured to apply a superimposed direct current of the same polarity.
ブレード７としては、ウレタン、ＮＢＲ、シリコンなど
の導電性ゴムを用い、体積抵抗１０６００ｍ以下、硬度
５０〜９０°（ＪＩＳ Ａ）のものが好適に使用でき
る。As the blade 7, a conductive rubber such as urethane, NBR, silicone, etc., having a volume resistance of 10,600 m or less and a hardness of 50 to 90 degrees (JIS A) can be suitably used.
このように構成することによって、全体としての構成を
簡単にすることが可能である。By configuring in this way, it is possible to simplify the overall configuration.
第７図はさらに他の実施例を示すもので、この装置にお
いては、除電手段として導電性ローラ９を配設し、これ
に交流または交流に直流を重畳した電圧を印加している
。FIG. 7 shows yet another embodiment, in which a conductive roller 9 is provided as a static eliminating means, and an alternating current or a voltage in which alternating current and direct current are superimposed is applied to it.
ローラ９としては、ＥＰＤＭ、シリコン、クロロプレン
などの導電性ゴムを用いるものとし、体積抵抗ｉｏ＠Ω
ｃｍ以下、硬度３０−７０’ （ＪＩＳ Ａ）のもの
が好適である。The roller 9 is made of electrically conductive rubber such as EPDM, silicone, or chloroprene, and has a volume resistance of io@Ω.
cm or less and a hardness of 30-70' (JIS A) is suitable.
この装置によるときは、転写ベルト表面の均一な除電が
可能であり、耐久性にすぐれた装置を得ることができる
。When using this device, it is possible to uniformly eliminate static electricity on the surface of the transfer belt, and a device with excellent durability can be obtained.
第８図は本発明のさらにまた他の実施例を示すものであ
る。FIG. 8 shows yet another embodiment of the present invention.
この装置においては、導電性ローラ８に予め転写電界と
は逆極性の電圧を印加しておき、給電ブラシには転写電
界と同極性の転写バイアスが印加しである。In this device, a voltage having a polarity opposite to that of the transfer electric field is applied to the conductive roller 8 in advance, and a transfer bias having the same polarity as the transfer electric field is applied to the power supply brush.
第９Ａ図、第９Ｂ図は上記装置の転写ベルトの表面電位
の推移を示すものである。FIGS. 9A and 9B show changes in the surface potential of the transfer belt of the above device.
図の工の部分は、転写電界と逆極性の電圧が印加された
導電性ローラ８に当接しており、このとき該ローラには
一１０００Ｖが印加されていて、導電ブラシ５によって
除電作用が行なわれて転写ベルト表面電位をＯＶに接近
させる傾向となる。The part shown in the figure is in contact with a conductive roller 8 to which a voltage of opposite polarity to the transfer electric field is applied. This tends to cause the transfer belt surface potential to approach OV.
図示の装置の場合、−５００Ｖ程度まで除電が行なわれ
る。この場合、導電ブラシ５に交流または転写電界と同
極性の電圧を印加してＯｖ程度にすることも可能である
。In the case of the illustrated device, static elimination is performed up to about -500V. In this case, it is also possible to apply an alternating current or a voltage of the same polarity as the transfer electric field to the conductive brush 5 to make it approximately Ov.
転写ベルト３が導電性ローラ８から分離して転写ニップ
部に至る間、符号Ｈの部分においては、＋１０００Ｖの
転写バイアスが印加されている給電ブラシ２の存在によ
って、第９Ａ図々示のような電位勾配が発生する。ピー
ク時には導電ブラシ５による除電分が上乗せされて約１
５００Ｖの表面電位が表われる。While the transfer belt 3 separates from the conductive roller 8 and reaches the transfer nip portion, at the portion marked H, due to the presence of the power supply brush 2 to which a transfer bias of +1000V is applied, the image as shown in Fig. 9A is generated. A potential gradient occurs. At the peak, the amount of static electricity removed by the conductive brush 5 is added, and the charge is approximately 1
A surface potential of 500V appears.
このように導電性ローラ８に転写電界と逆極性の電圧を
印加することによって、トナーを転写ベルト３の方向の
へ引きつける表面電位が表われる部分の電位を制御する
ことができ、転写材が感光体に当接する以前に転写が行
なわれるのを確実に阻止することができる。By applying a voltage of opposite polarity to the transfer electric field to the conductive roller 8 in this manner, it is possible to control the potential of the portion where the surface potential that attracts the toner toward the transfer belt 3 appears, and the transfer material becomes photosensitive. It is possible to reliably prevent transfer from occurring before it comes into contact with the body.
以上の説明から判るように、感光体１と転写ベルト３と
が当接する転写部位または該ベルトの走行方向にみて下
流側近傍位置に配設した導電性部材（図示の装置におけ
る給電ブラシ２）と、転写ベルト３の表面電位制御部材
（同導電ブラシ５）および転写部位の上流側に配設した
導電性部材（同導電性ローラ８）の３者の電位を適宜調
整することによって、所望の電位勾配を得ることができ
る。As can be seen from the above description, the conductive member (the power supply brush 2 in the illustrated device) disposed at the transfer site where the photoreceptor 1 and the transfer belt 3 are in contact with each other or at a position near the downstream side in the running direction of the belt. By appropriately adjusting the potentials of the surface potential control member (conductive brush 5) of the transfer belt 3 and the conductive member (conductive roller 8) disposed upstream of the transfer site, a desired potential can be achieved. You can get the gradient.
転写ベルトが感光体から分離するさいの剥離放電によっ
て、分離後は第９Ａ図ｍに示すような電位勾配となり、
該ベルトが導電性駆動ローラ４に当接する部分近傍にお
いて、その表面電位はほぼＯＶになる。Due to peeling discharge when the transfer belt separates from the photoreceptor, the potential gradient after separation becomes as shown in Figure 9A m.
In the vicinity of the portion where the belt contacts the conductive drive roller 4, the surface potential thereof becomes approximately OV.
前述のように、導電性ローラ８には一１０００Ｖの電圧
が印加されているので、駆動ローラ４から導電性ローラ
８に至る間における転写ベルトの表面電位は第９Ａ図の
符号■で示すような電位勾配を示す。As mentioned above, since a voltage of -1000 V is applied to the conductive roller 8, the surface potential of the transfer belt from the drive roller 4 to the conductive roller 8 is as shown by the symbol ■ in FIG. 9A. Shows potential gradient.
この実施例装置の構成によるときは、転写ベルトの表面
電位勾配を、より細かく制御することができ、トナーの
“とびちり°゛がなく、安定した転写効率で、感光体上
の画像の忠実な転写、画像を乱すことなく確実な転写材
の分離を遂行することができる。With the configuration of this example device, the surface potential gradient of the transfer belt can be controlled more precisely, and the image on the photoreceptor can be faithfully transferred without toner scattering and with stable transfer efficiency. , it is possible to reliably separate the transfer material without disturbing the image.
（３）発明の詳細
な説明したように、本発明によるときは、感光体とこれ
に当接する転写ベルトをそなえ、該転写ベルトに転写材
を転写材を吸着、搬送するように構成した画像形成装置
において、転写ベルトの表面電位を、所望の電位勾配を
有するように制御することが可能で、環境特性にすぐれ
、トナーのとびちりや中抜けがなく、高転写率で安定的
に忠実な転写が可能であって、良質の画像を得るのに資
するところが極めて大である。(3) As described in detail, the present invention provides an image forming system comprising a photoreceptor and a transfer belt in contact with the photoreceptor, and configured to adsorb and convey a transfer material to the transfer belt. In the device, it is possible to control the surface potential of the transfer belt to have the desired potential gradient, and it has excellent environmental characteristics, eliminates toner scattering and hollow spots, and provides stable and faithful transfer at a high transfer rate. This is possible and greatly contributes to obtaining high-quality images.
また、コロナ帯電器を使用しないので、オゾンその他コ
ロナ生成物による感光体表面、転写ベルト表面の劣化を
招来するおそれが少ないので耐久性にすぐれ、低バイア
ス電圧ですむので電源コストの面からも有利である。In addition, since a corona charger is not used, there is less risk of deterioration of the photoreceptor surface and transfer belt surface due to ozone and other corona products, resulting in excellent durability, and low bias voltage is required, which is advantageous in terms of power supply costs. It is.
さらに、転写ベルト表面にピンホールがあっても転写不
良を発生することがないため、転写ベルト表面絶縁層を
薄くすることができるので、高転写率が得られるととも
に転写ベルトの製作歩留りの向上によるコストダウンに
も有効である。Furthermore, even if there are pinholes on the transfer belt surface, transfer defects will not occur, so the insulating layer on the transfer belt surface can be made thinner, resulting in a high transfer rate and improved transfer belt manufacturing yield. It is also effective in reducing costs.
第１図は本発明の実施例たる画像形成装置の構成を示す
概略側面図、
第２図は同上転写ベルトの構成を示す断面図、第３Ａ図
、第３Ｂ図は、それぞれ前記実施例装置の転写ベルト表
面電位勾配図および該ベルトの表面の区分図。
第４図は本発明の他の実施例を示す画像形成装置の側面
図、
第５Ａ図、第５Ｂ図は、それぞれ上記実施例装置の転写
ベルトの表面電位勾配図および該ベルトの表面の区分図
、
第６図、第７図はいずれも本発明の他の実施例を示す概
略側面図、
第８図は本発明のさらに他の実施例を示す画像形成装置
の概略側面図。
第９Ａ図、第９Ｂ図は、それぞれ上記実施例装置の転写
ベルトの表面電位勾配図および該ベルトの表面の区分図
である。
ｌ・・・感光体、２・・ゆ給電ブラシ、３・・・転写ベ
ルト、４・・管駆動ローラ、５・・・導電ブラシ、７・
・番クリーニングブレード、８・ａ番導電性ローラ。
弗３Ａ図
第３Ｂ図
第４二ｉ
第５Ａ図
！８′
第５Ｂ図
第
図
第
図
第
図
第９Ａ図
第９Ｂ
「１
し会ｊFIG. 1 is a schematic side view showing the structure of an image forming apparatus according to an embodiment of the present invention, FIG. 2 is a sectional view showing the structure of the same transfer belt, and FIGS. 3A and 3B are respectively of the above-mentioned embodiment apparatus. FIG. 3 is a transfer belt surface potential gradient diagram and a section diagram of the surface of the belt. FIG. 4 is a side view of an image forming apparatus showing another embodiment of the present invention, and FIGS. 5A and 5B are a surface potential gradient diagram and a section diagram of the surface of the transfer belt of the above embodiment apparatus, respectively. , FIG. 6 and FIG. 7 are both schematic side views showing another embodiment of the present invention, and FIG. 8 is a schematic side view of an image forming apparatus showing still another embodiment of the present invention. FIG. 9A and FIG. 9B are a surface potential gradient diagram of the transfer belt of the above-mentioned embodiment apparatus and a section diagram of the surface of the belt, respectively. l... Photoreceptor, 2... Power supply brush, 3... Transfer belt, 4... Tube drive roller, 5... Conductive brush, 7...
・No. cleaning blade, 8・A conductive roller.弗3A Figure 3B Figure 42i Figure 5A! 8' Fig. 5B Fig. Fig. 9A Fig. 9B
Claims (2)
とともに転写材をこの位置に吸着、搬送する転写材吸着
搬送手段とをそなえ、該転写材吸着搬送手段の転写材と
当接する面と反対側に、像担持体のトナー像を転写材に
移動させる方向に電界を発生させる電界発生手段を配設
した画像形成装置において、 前記転写材吸着搬送手段の、前記像担持体に当接する側
に体積抵抗が１０＾１＾４Ωｃｍ以上の絶縁層を、その
反対側に体積抵抗が１０＾１＾４Ωｃｍ以下の高抵抗層
を形成してなる画像形成装置。(1) An image carrier is provided with a transfer material adsorption/conveyance means that comes into contact with the image carrier to form a transfer site, and also attracts and conveys the transfer material to this position, and comes into contact with the transfer material of the transfer material adsorption/conveyance means. In an image forming apparatus in which an electric field generating means for generating an electric field in a direction to move a toner image on an image carrier to a transfer material is disposed on the opposite side to the surface, an electric field generating means for generating an electric field in a direction to move a toner image on an image carrier to a transfer material is provided. An image forming apparatus comprising an insulating layer having a volume resistivity of 10^1^4 Ωcm or more on the side in contact with the insulating layer, and a high resistance layer having a volume resistivity of 10^1^4 Ωcm or less on the opposite side.
材に当接する側の表面電位が、該転写材吸着搬送手段の
走行方向にみて、像担持体と転写材吸着搬送手段との当
接部ないしはその下流側近傍位置にピークを有する電位
勾配を形成する特許請求の範囲第１項記載の画像形成装
置。(2) The surface potential of the side of the transfer material adsorption/conveyance unit that comes into contact with the transfer material due to the electric field generation unit is such that the image carrier and the transfer material adsorption/conveyance unit come into contact with each other when viewed in the traveling direction of the transfer material adsorption/conveyance unit. 2. The image forming apparatus according to claim 1, wherein a potential gradient is formed having a peak at or near the downstream side thereof.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63262768A JPH02110586A (en) | 1988-10-20 | 1988-10-20 | Image forming device |
| US07/401,121 US5172173A (en) | 1988-09-01 | 1989-08-31 | Image forming device and transfer belt having contact-type electricity feeding means |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63262768A JPH02110586A (en) | 1988-10-20 | 1988-10-20 | Image forming device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH02110586A true JPH02110586A (en) | 1990-04-23 |
Family
ID=17380321
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63262768A Pending JPH02110586A (en) | 1988-09-01 | 1988-10-20 | Image forming device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02110586A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0552730A2 (en) * | 1992-01-22 | 1993-07-28 | Ricoh Company, Ltd | Image transferring device for image forming equipment |
| EP0568829A2 (en) * | 1992-04-09 | 1993-11-10 | Ricoh Company, Ltd | Image forming apparatus |
| US5268725A (en) * | 1990-11-19 | 1993-12-07 | Mita Industrial Co., Ltd. | Sheet member carrier device with grounding means |
| US5461461A (en) * | 1992-01-22 | 1995-10-24 | Ricoh Company, Ltd. | Image transferring device and medium separating device for an image forming apparatus |
| US5659843A (en) * | 1992-01-22 | 1997-08-19 | Ricoh Company, Ltd. | Image transferring device for image forming equipment |
| DE19820249C2 (en) * | 1997-10-06 | 2001-03-01 | Ricoh Kk | A conveying member for conveying a recording medium in an image forming apparatus and an image forming apparatus having this conveying member |
| JP2006091079A (en) * | 2004-09-21 | 2006-04-06 | Fuji Xerox Co Ltd | Image forming apparatus |
-
1988
- 1988-10-20 JP JP63262768A patent/JPH02110586A/en active Pending
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5268725A (en) * | 1990-11-19 | 1993-12-07 | Mita Industrial Co., Ltd. | Sheet member carrier device with grounding means |
| EP0733957A2 (en) * | 1992-01-22 | 1996-09-25 | Ricoh Company, Ltd | Image transferring device with charging control |
| EP0552730A3 (en) * | 1992-01-22 | 1994-04-27 | Ricoh Kk | |
| US5461461A (en) * | 1992-01-22 | 1995-10-24 | Ricoh Company, Ltd. | Image transferring device and medium separating device for an image forming apparatus |
| EP0552730A2 (en) * | 1992-01-22 | 1993-07-28 | Ricoh Company, Ltd | Image transferring device for image forming equipment |
| US5640660A (en) * | 1992-01-22 | 1997-06-17 | Ricoh Company, Ltd. | Image transferring device for image forming equipment |
| US5659843A (en) * | 1992-01-22 | 1997-08-19 | Ricoh Company, Ltd. | Image transferring device for image forming equipment |
| US5666622A (en) * | 1992-01-22 | 1997-09-09 | Ricoh Company, Ltd. | Image transferring device and medium separating device for an image forming apparatus |
| EP0733957A3 (en) * | 1992-01-22 | 1998-01-07 | Ricoh Company, Ltd | Image transferring device with charging control |
| EP0568829A2 (en) * | 1992-04-09 | 1993-11-10 | Ricoh Company, Ltd | Image forming apparatus |
| EP0568829A3 (en) * | 1992-04-09 | 1995-05-10 | Ricoh Kk | Image forming apparatus. |
| DE19820249C2 (en) * | 1997-10-06 | 2001-03-01 | Ricoh Kk | A conveying member for conveying a recording medium in an image forming apparatus and an image forming apparatus having this conveying member |
| JP2006091079A (en) * | 2004-09-21 | 2006-04-06 | Fuji Xerox Co Ltd | Image forming apparatus |
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