JP3080426B2 - Developing device - Google Patents
Developing deviceInfo
- Publication number
- JP3080426B2 JP3080426B2 JP03080116A JP8011691A JP3080426B2 JP 3080426 B2 JP3080426 B2 JP 3080426B2 JP 03080116 A JP03080116 A JP 03080116A JP 8011691 A JP8011691 A JP 8011691A JP 3080426 B2 JP3080426 B2 JP 3080426B2
- Authority
- JP
- Japan
- Prior art keywords
- electric field
- developer
- latent image
- electrostatic latent
- alternating electric
- 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.)
- Expired - Lifetime
Links
Landscapes
- Developing For Electrophotography (AREA)
- Dry Development In Electrophotography (AREA)
Description
【0001】[0001]
【産業上の利用分野】本発明は、静電潜像を担持する静
電潜像担持体と現像剤を担持した現像剤担持体とを現像
部において対向させ、現像部においてバイアスを印加し
て現像を行う電子複写機、プリンタ、ファクシミリ等の
画像形成装置に用いる現像装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device in which an electrostatic latent image carrier for carrying an electrostatic latent image is opposed to a developer carrier for carrying a developer, and a bias is applied to the developing unit. The present invention relates to a developing device used for an image forming apparatus such as an electronic copying machine, a printer, and a facsimile that performs development.
【0002】[0002]
【従来の技術】一成分現像剤を使用する前記の現像装置
において、画像の再現性と階調生にすぐれた可視像を得
るために、静電潜像担持体と現像剤担持体との間の現像
間隙に、バイアスとして第1交互電界とこの第1交互電
界より高周波の第2交互電界を重畳した交互電界を与え
ることは、既に提案されている(特公昭63−2118
7号公報参照)。この第1の提案の概要を、図1および
図2により説明する。2. Description of the Related Art In the above-described developing apparatus using a one-component developer, in order to obtain a visible image excellent in image reproducibility and gradation, an electrostatic latent image carrier and a developer carrier are connected. It has already been proposed to provide, as a bias, an alternating electric field in which a first alternating electric field and a second alternating electric field having a higher frequency than the first alternating electric field are superimposed on the developing gap therebetween (Japanese Patent Publication No. 63-2118).
No. 7). An outline of the first proposal will be described with reference to FIGS.
【0003】図1に示す現像装置2のケーシングには、
静電潜像担持体としての感光体ドラム3に対向する部分
に現像用の開口が設けられており、現像剤担持体として
の現像ローラ1はこの開口を介して感光体ドラム3に所
定の間隙を保持してケーシング内に回転可能に設けられ
ている。現像ローラ1の周囲には、該ローラ1に担持搬
送されるトナー層の層厚を規制するブレード部材4がロ
ーラ1の上方に弾発的に圧接するように設けられてお
り、これによりケーシング内に形成されたトナータンク
5からアジテータ6及びトナー供給ローラ8の回転にと
もない供給されたトナー7を層厚規制するようにされて
いる。このブレード部材4に代え、規制ローラや規制ベ
ルトを用いても良い。アジテータ6は矢印で示す時計方
向に回転し、その先端部分の抵抗でトナー7を攪拌する
と共に図において左方に移動させる。The casing of the developing device 2 shown in FIG.
An opening for development is provided in a portion facing the photosensitive drum 3 as an electrostatic latent image carrier, and a developing roller 1 as a developer carrier is provided with a predetermined gap through the opening to the photosensitive drum 3. And rotatably provided in the casing. Around the developing roller 1, a blade member 4 for regulating the thickness of the toner layer carried and conveyed by the roller 1 is provided so as to resiliently press the roller 1 above the roller 1. The thickness of the toner 7 supplied from the toner tank 5 formed in accordance with the rotation of the agitator 6 and the toner supply roller 8 is regulated. Instead of the blade member 4, a regulating roller or a regulating belt may be used. The agitator 6 rotates clockwise as indicated by the arrow, and agitates the toner 7 by the resistance of the tip thereof and moves the toner 7 to the left in the drawing.
【0004】上記のトナー供給ローラ8は、アジテータ
6により搬送されてきたトナー7を現像ローラ1の表面
に順方向あるいは逆方向にこすり付けて供給すると共
に、現像に使用されずに現像ローラ1上に残って戻って
きたトナー7を掻き落す作用をするものである。The toner supply roller 8 supplies the toner 7 conveyed by the agitator 6 to the surface of the developing roller 1 by rubbing the surface of the developing roller 1 in the forward or reverse direction. And has the function of scraping off the toner 7 that has returned and returned.
【0005】トナー供給ローラ8により現像ローラ1の
表面に供給されたトナー7は、トナー供給ローラ8又は
現像ローラ1との相互摩擦により発生する摩擦帯電作用
により、トナー7自体も帯電して現像ローラ1の表面に
静電的に担持される。かくして現像ローラ1に担持搬送
されるトナー7は、現像ローラ1の上方に弾発的に圧接
するブレード部材4により層厚規制され、感光体ドラム
3と現像ローラ1とが対向する現像部に搬送される。ブ
レード部材4は、弾性を有する板ばねにウレタンゴム等
のトナー帯電性能を有する材料を貼り合わせて製作して
も、あるいは弾性を有する部材をそのまま用いても良
い。ブレード部材4は、現像ローラ1の回転方向に対し
て図に示すごとくトレーリング方向に設けても良いし、
逆方向のリーディング方向に設けても良い。[0005] The toner 7 supplied to the surface of the developing roller 1 by the toner supply roller 8 is also charged by the frictional charging effect generated by mutual friction with the toner supply roller 8 or the developing roller 1, and the toner 7 itself is also charged. 1 is electrostatically carried on the surface. Thus, the thickness of the toner 7 carried and transported by the developing roller 1 is regulated by the blade member 4 which resiliently presses above the developing roller 1, and is transported to the developing section where the photosensitive drum 3 and the developing roller 1 are opposed to each other. Is done. The blade member 4 may be manufactured by attaching a material having a toner charging property such as urethane rubber to an elastic leaf spring, or may use an elastic member as it is. The blade member 4 may be provided in the trailing direction as shown in the drawing with respect to the rotation direction of the developing roller 1,
It may be provided in the reverse reading direction.
【0006】9は低周波交互電圧印加用電源、10は高
周波電圧印加用電源であり、重畳して現像ローラ1とト
ナー供給ローラ8との間隙に供給される。これにより印
加される交互電圧波形を、図2に示す。同図において、
静電潜像の電位は、画像部電位(VD)が700V、非
画像部電位(VL)が200V、そして第1交互電界を
与える低周波電圧は最高値が800V、最低値が−10
0Vの矩形波であり、これに周波数5KHz振幅600
Vの第2の交互電界を与える高周波正弦波が重畳されて
いる。Reference numeral 9 denotes a power supply for applying a low frequency alternating voltage, and reference numeral 10 denotes a power supply for applying a high frequency voltage, which is supplied to a gap between the developing roller 1 and the toner supply roller 8 in a superimposed manner. FIG. 2 shows the waveform of the alternating voltage applied thereby. In the figure,
The potential of the electrostatic latent image is such that the image portion potential (V D ) is 700 V, the non-image portion potential (V L ) is 200 V, and the low frequency voltage that gives the first alternating electric field has a maximum value of 800 V and a minimum value of −10.
It is a rectangular wave of 0 V, which has a frequency of 5 kHz and an amplitude of 600.
A high frequency sine wave giving a second alternating electric field of V is superimposed.
【0007】上述のように、異なる周波数の第1、第2
交互電界を重畳して印加することにより、トナーは現像
ローラ1から感光体ドラム4への転移と逆転移を確実に
行い感光体ドラム4の非画像部に積極的に付着させたト
ナーを確実に該非画像部から回収することが出来る。As described above, the first and second signals having different frequencies are used.
By applying the alternating electric field in a superimposed manner, the toner is surely transferred from the developing roller 1 to the photosensitive drum 4 and reversely transferred, and the toner positively adhered to the non-image portion of the photosensitive drum 4 is reliably obtained. It can be collected from the non-image portion.
【0008】図1に示す現像装置に外部電極を印加しな
いときは、V−D曲線(静電潜像電位Vに対する画像濃
度Dの特性曲線)の傾きγ値は非常に大きいが、前記の
交互電界を印加することでγ値が小さくなり、階調性が
向上するとともに、高濃度の画像を得ることができる。When no external electrode is applied to the developing device shown in FIG. 1, the slope γ value of the VD curve (characteristic curve of the image density D with respect to the electrostatic latent image potential V) is very large. By applying an electric field, the γ value is reduced, the gradation is improved, and a high-density image can be obtained.
【0009】更に、図1に示す現像装置において、感光
体ドラム3と現像ローラ1との間でトナーが往復運動す
る第1工程と、この第1工程よりは後であって感光体ド
ラム3の非画像部から現像ローラ1へトナーが移動する
第2工程とを有し、該第1工程には第1交互電界を、そ
して該第2工程には第1交互電界の強度より小の交互電
界と第1交互電界よりも高周波の第2交互電界の重畳交
互電界を与えて現像を行うことは、既に提案されている
(特公昭63−21188号公報)。Further, in the developing device shown in FIG. 1, a first step in which the toner reciprocates between the photosensitive drum 3 and the developing roller 1 is performed. A second step of transferring toner from the non-image area to the developing roller 1, wherein the first step includes a first alternating electric field, and the second step includes an alternating electric field smaller than the intensity of the first alternating electric field. It has already been proposed to apply a superimposed alternating electric field of a second alternating electric field higher in frequency than the first alternating electric field to perform development (Japanese Patent Publication No. 63-21188).
【0010】この第2の提案の第1工程では、現像ロー
ラ1と感光体ドラム3の非画像部との間にトナー粒子の
往復運動(転移一逆転移)を積極的に行わしめる構成で
あり、この過程においては、非画像部へのトナーの付着
を積極的に起こさせている。これは、地カブリの原因と
なるが、この地カブリは次の第2工程で除去される。他
方、非画像部にもトナーを付着させ得るこの第1工程に
おいては、静電像としての電位を有する画像部において
は、その付着は更に強化される。従って、所謂ハーフ・
トーンを含む中間調画像部分の明部に近接した濃度を有
する部分においても、その電位に応じてトナーが付着す
る。In the first step of the second proposal, the toner particles are positively reciprocated (transition-reverse transition) between the developing roller 1 and the non-image portion of the photosensitive drum 3. In this process, toner is positively attached to the non-image portion. This causes ground fog, which is removed in the next second step. On the other hand, in the first step in which the toner can be adhered to the non-image area, the adhesion is further enhanced in the image area having a potential as an electrostatic image. Therefore, the so-called half
Even in a portion having a density close to a bright portion of a halftone image portion including a tone, toner adheres according to the potential.
【0011】前記の第2工程で印加する高周波電界は、
現像過程において常にトナーを揺動状態に保ち、現像ロ
ーラ又は潜像形成面への強い拘束からトナーを解きほぐ
す効果をもつものである。これにより、先に述べた現象
の第1工程の現象促進段階において非画像部に転移して
いるトナーは、第2工程において容易に現像ローラ側へ
戻る。The high-frequency electric field applied in the second step is as follows:
In the developing process, the toner is always kept in a swinging state, and has an effect of releasing the toner from strong restraint on the developing roller or the latent image forming surface. As a result, the toner transferred to the non-image portion in the phenomenon promoting stage of the first step of the phenomenon described above easily returns to the developing roller side in the second step.
【0012】[0012]
【発明が解決しようとする課題】静電潜像担持体と現像
剤担持体との間の現像間隙に外部電界を印加しない場合
には、V−D曲線の傾き所謂γ値は非常に大きいが、前
記の第1提案および第2提案に従い低周波の交互電界を
印加することによって、γ値は小さくなり、階調性が高
くなることがわかる。外部電界の周波数を上げると、次
第にγ値は大きくなり、階調性を高からしめる効果は薄
れていき、間隙が100μの場合、周波数が1KHzを
越えると効果が極めて弱くなり、又間隙が300μの場
合、周波数が800Hz程度になると効果が減少し、1
KHzを越えると効果が極めて弱くなる。更に、副作用
として地カブリが発生する欠点がある。本発明は、地カ
ブリのない高階調性の現像装置を提供することを課題と
する。When no external electric field is applied to the developing gap between the electrostatic latent image carrier and the developer carrier, the slope of the VD curve, the so-called γ value, is very large. It can be seen that by applying a low-frequency alternating electric field according to the first and second proposals, the γ value is reduced and the gradation is improved. When the frequency of the external electric field is increased, the γ value gradually increases, and the effect of increasing the gradation becomes weaker. When the gap is 100 μ, the effect becomes extremely weak when the frequency exceeds 1 KHz, and the gap becomes 300 μ. In the case of, the effect decreases when the frequency is about 800 Hz, and 1
If it exceeds KHz, the effect becomes extremely weak. Further, there is a disadvantage that ground fog occurs as a side effect. SUMMARY OF THE INVENTION It is an object of the present invention to provide a developing device having a high gradation with no background fog.
【0013】[0013]
【課題を解決するための手段】前記の課題は、本発明に
より、表面に多数の微小閉電界を形成する現像剤担持体
と、第1交互電界と第1交互電界より高周波の第2交互
電界を重畳した交互電界を形成するバイアスを印加する
手段とを有し、前記現像部にて、前記静電潜像担持体上
の電位と前記バイアスによる電界と前記現像剤担持体上
の微小閉電界とにより決定される電界により、前記現像
剤担持体に保持された前記現像剤の前記静電潜像担持体
への転移、逆転移を行って現像することにより解決され
る。SUMMARY OF THE INVENTION According to the present invention, there is provided a developer carrier for forming a plurality of minute closed electric fields on a surface thereof, a first alternating electric field, and a second alternating electric field having a higher frequency than the first alternating electric field. Means for applying a bias to form an alternating electric field in which the electric field is superimposed on the electrostatic latent image carrier, an electric field due to the bias, and a minute closed electric field on the developer carrier in the developing unit. The transfer of the developer held on the developer carrier to the electrostatic latent image carrier and the reverse transfer of the developer by the electric field determined by the formula (1) and development are performed.
【0014】更に、前記の課題は、本発明により、表面
に多数の微小閉電界を形成する現像剤担持体と、第1工
程として第1交互電界を形成するバイアスを印加する手
段と、第2工程として第1交互電界より小さい交互電界
と第1交互電界より高周波の第2交互電界を重畳した交
互電界を形成するバイアスを印加する手段とを有し、前
記現像部にて、前記静電潜像担持体上の電位と前記バイ
アスによる電界と前記現像剤担持体上の微小閉電界とに
より決定される電界により、前記現像剤担持体に保持さ
れた前記現像剤の前記静電潜像担持体への転移、逆転移
を行って現像することにより解決される。Further, according to the present invention, there is provided a developer carrier for forming a large number of micro-closed electric fields on a surface thereof, means for applying a bias for forming a first alternating electric field as a first step, and a second step. Means for applying a bias for forming an alternating electric field in which an alternating electric field smaller than the first alternating electric field and a second alternating electric field having a higher frequency than the first alternating electric field are superimposed. The electrostatic latent image carrier of the developer held on the developer carrier by an electric field determined by the electric potential on the image carrier, the electric field due to the bias, and the minute closed electric field on the developer carrier The problem can be solved by performing the transfer to the reverse transfer and the reverse transfer and developing.
【0015】[0015]
【作用】表面に多数の微小閉電界を形成した現像剤担持
体は、所望のトナー付着量およびトナー帯電量が得られ
るが、反面誘電体部の電荷によりトナーを保持している
ので、トナー剥離性が悪く、その結果現像剤担持体から
静電潜像担持体へのトナー転移率が低下する。これに対
し、第1交互電界の低周波電圧を印加することにより、
γ特性の良い画像が得られるとともに、高周波の第2交
互電界により、トナーを揺動状態に保ち、現像剤担持体
又は潜像形成面への強い拘束から解きほぐし、前記のト
ナー転移率の低下を防止する。The developer carrier having a large number of minute closed electric fields on its surface can provide a desired amount of toner adhesion and toner charge. On the other hand, since the toner is held by the electric charge of the dielectric portion, the toner is peeled off. As a result, the toner transfer rate from the developer carrier to the electrostatic latent image carrier is reduced. On the other hand, by applying the low frequency voltage of the first alternating electric field,
An image having good γ characteristics can be obtained, and the toner is kept in a oscillating state by the high frequency second alternating electric field, and the toner is released from the strong restraint on the developer carrier or the latent image forming surface, thereby reducing the toner transfer rate. To prevent.
【0016】[0016]
【実施例】図1に示す現像装置2において、現像ローラ
1と感光体ドラム3との間には、既述のように、低周波
交互電圧印加用電源9より第1交互電界と、高周波電圧
印加用電源10より前記第1交互電界より高周波の第2
電界が重畳して与えられる。 更に、前記現象ローラは
本発明に従って、次のように構成される。DESCRIPTION OF THE PREFERRED EMBODIMENTS In a developing device 2 shown in FIG. 1, between a developing roller 1 and a photosensitive drum 3, a first alternating electric field and a high frequency voltage are supplied from a power supply 9 for applying a low frequency alternating voltage as described above. A second power source having a frequency higher than that of the first alternating electric field from a power source for application
An electric field is provided superimposed. Further, according to the present invention, the phenomenon roller is configured as follows.
【0017】現像ローラ1は、図3に示すように、その
表面に誘電体部11(弾性絶縁粒子)と導電体部12
(弾性導電性材料)とが微小面積で混在するように構成
されている。As shown in FIG. 3, the developing roller 1 has a dielectric portion 11 (elastic insulating particles) and a conductive portion 12 on its surface.
(Elastic conductive material) in a small area.
【0018】トナー付着は次のようになる。まず、現像
を終了した現像ローラ1は、矢印の方向に回転してトナ
ー供給ローラ8と接触する。ここで現像しなかった非画
像部の残トナーは、トナー供給ローラ8により機械的、
電気的にかきとられ、誘電体部は摩擦によって帯電す
る。このとき、前の現像による現像ローラ1とトナーの
電荷は、摩擦により一定化され、初期化される。次に、
トナー供給ローラ8によって運ばれたトナーは、摩擦に
より帯電し、現像ローラ1の誘電体部に静電的に付着す
る。このときの極性は、感光体電荷に対してトナーは逆
極性に、また現像ローラ1の誘電体部は同極性となる。
このときの現像ローラ1上の電界は、図3に示されるよ
うにマイクロフィールド(閉電界)13となり、電界傾
度の大きい電界となって、トナーを多層に付着させるこ
とが可能となる。また、付着したトナーは閉電界となっ
ているので、現像ローラ1側に強く引かれ離れにくい状
態となる。このトナー層は、更にトナー層厚を規制する
ブレード部材4によりトナー層厚が制御され、現像域の
トナーは感光体に付着し易い電界となり、現像が行なわ
れる。The toner adhesion is as follows. First, the developing roller 1 that has completed the development rotates in the direction of the arrow and comes into contact with the toner supply roller 8. Here, the remaining toner in the non-image area which has not been developed is mechanically and
It is scraped off electrically and the dielectric part is charged by friction. At this time, the charge of the developing roller 1 and the toner by the previous development is fixed by friction and initialized. next,
The toner conveyed by the toner supply roller 8 is charged by friction, and electrostatically adheres to the dielectric portion of the developing roller 1. At this time, the polarity of the toner is opposite to the charge of the photoconductor, and the dielectric portion of the developing roller 1 has the same polarity.
At this time, the electric field on the developing roller 1 becomes a microfield (closed electric field) 13 as shown in FIG. 3, and becomes an electric field having a large electric field gradient, so that the toner can be adhered in multiple layers. Further, since the adhered toner has a closed electric field, it is strongly pulled toward the developing roller 1 and hardly separated. The thickness of the toner layer is further controlled by a blade member 4 that regulates the thickness of the toner layer, so that the toner in the development area becomes an electric field that easily adheres to the photoreceptor, and development is performed.
【0019】次に、前記の現像ローラ1について説明す
る。Next, the developing roller 1 will be described.
【0020】現像ローラ1は、前記したように少なくと
もその表面に導電体部12と誘電体部11が混在してな
り、かつこれらの形成材料は弾性絶縁性粒子を含有した
弾性導電性材料である。As described above, the developing roller 1 has at least the surface on which the conductor portion 12 and the dielectric portion 11 are mixed, and these forming materials are elastic conductive materials containing elastic insulating particles. .
【0021】誘電体部11を構成する弾性絶縁性粒子と
しては、体積抵抗が1013Ω・cm以上好ましくは10
14Ω・cm以上のもので、実効ゴム硬度(現像剤担持体
の形状をJIS K6301で定めるスプリング式硬さ
試験機A型を用いて測定したときの値)が50度以下好
ましくは40度以下のものが使用される。The elastic insulating particles constituting the dielectric portion 11 have a volume resistance of 10 13 Ω · cm or more, preferably 10 13 Ω · cm or more.
14 Ω · cm or more and an effective rubber hardness (a value obtained by measuring the shape of the developer carrying member using a spring-type hardness tester A type defined in JIS K6301) of 50 degrees or less, preferably 40 degrees or less Is used.
【0022】このような材料としては、たとえば、シリ
コーン変性エチレンプロピレンゴム、エピクロルヒドリ
ンゴム、ブチルゴム、シリコーンゴム、エチレンプロピ
レンゴムなどが挙げられる。その平均粒径は5μm以上
好ましくは10μm以上である。5μm未満ではマイク
ロフィールドが形成し難く、安定したトナーの付着、帯
電が得られない。また、粒子形状は定形あるいは不定形
のいずれでもよい。Examples of such materials include silicone-modified ethylene propylene rubber, epichlorohydrin rubber, butyl rubber, silicone rubber, and ethylene propylene rubber. The average particle size is 5 μm or more, preferably 10 μm or more. If it is less than 5 μm, it is difficult to form a microfield, and stable toner adhesion and charging cannot be obtained. Further, the particle shape may be either a regular shape or an irregular shape.
【0023】また、弾性導電性材料としては、体積固有
抵抗が1012Ω・cm以下好ましくは108Ω・cm以
下のものがよく、また実効ゴム硬度(既出)が50度以
上好ましくは40度以下ゴム類に導電性フィラーを添加
したものが使用される。The elastic conductive material preferably has a volume resistivity of 10 12 Ω · cm or less, preferably 10 8 Ω · cm or less, and has an effective rubber hardness of 50 degrees or more, preferably 40 degrees or less. Hereinafter, those obtained by adding a conductive filler to rubbers are used.
【0024】ゴム類としては、シリコーン変性エチレン
−プロピレンゴム、スチレン−ブタジエンゴム、エピク
ロルヒドリンゴム、エチレン−プロピレンゴム、ウレタ
ンゴム、フッ素ゴム、シリコーンゴム、ニトリルゴム、
アクリルゴム、ブチルゴム、イソプレンゴムなどが挙げ
られる。The rubbers include silicone-modified ethylene-propylene rubber, styrene-butadiene rubber, epichlorohydrin rubber, ethylene-propylene rubber, urethane rubber, fluorine rubber, silicone rubber, nitrile rubber,
Acrylic rubber, butyl rubber, isoprene rubber and the like can be mentioned.
【0025】また、導電性フィラーとしては、Ni、C
uなどの金属粉;ファーネスブラック、ランプブラッ
ク、サーマルブラック、アセチレンブラック、チャンネ
ルブラックなどのカーボンブラック;酸化スズ、酸化亜
鉛、酸化モリブデン、酸化アンチモン、チタン酸カリな
どの導電性酸化物;酸化チタン、雲母上などにめっきを
施した無電界めっき物;グラファイト、金属繊維、炭素
繊維などが挙げられる。Further, as the conductive filler, Ni, C
metal powders such as u; carbon blacks such as furnace black, lamp black, thermal black, acetylene black, and channel black; conductive oxides such as tin oxide, zinc oxide, molybdenum oxide, antimony oxide, and potassium titanate; An electroless plating product plated on mica or the like; graphite, metal fiber, carbon fiber, and the like.
【0026】図4に示す現像ローラ1は、導電性金属ロ
ーラ14上に絶縁性粒子15を分散固着した導電性材料
の基本16からなる表面層が形成されている。導電性材
料としては、図3に示す現像ローラと同じく、1012Ω
・cm以下、好ましくは108Ω・cm以下のものが使
用できる。具体的にいうと、有機ポリマー類に導電性付
与剤を添加したものが挙げられる。この場合、有機ポリ
マー類としては樹脂材料(プラストマー)とゴム材料
(エラストマー)がある。The developing roller 1 shown in FIG. 4 has a surface layer made of a conductive material base 16 in which insulating particles 15 are dispersed and fixed on a conductive metal roller 14. As the conductive material, like the developing roller shown in FIG. 3, 10 12 Omega
Cm or less, preferably 10 8 Ωcm or less. To be specific, there may be mentioned those obtained by adding a conductivity-imparting agent to organic polymers. In this case, the organic polymers include a resin material (plastomer) and a rubber material (elastomer).
【0027】現像ローラ1は、導電性材料に絶縁性粒子
を、ボールミル、練り込みなど通常の分散方法に基いて
添加した後、該混合材料を射出成型、押し出し成型、ス
プレーコーティング、ディッピングなどの工法により、
SUS、鉄、Alなどの金属ローラに代表される導電性
金属ローラ上に成型し、その後表面が平滑になるように
研磨を施すことによって作製することができる。The developing roller 1 is prepared by adding insulating particles to a conductive material based on a normal dispersion method such as ball milling or kneading, and then subjecting the mixed material to a method such as injection molding, extrusion molding, spray coating, dipping, or the like. By
It can be manufactured by molding on a conductive metal roller typified by a metal roller of SUS, iron, Al, or the like, and then performing polishing so that the surface becomes smooth.
【0028】次に、図5に示す現像ローラ1は、その表
面に誘電体部17と導電体部18が微小面積で混在し、
かつ誘導体部17は導電性発泡体層の表面近傍の発泡セ
ル19中に形成されている。Next, in the developing roller 1 shown in FIG. 5, a dielectric portion 17 and a conductor portion 18 are mixed in a very small area on the surface thereof.
In addition, the derivative portion 17 is formed in the foam cell 19 near the surface of the conductive foam layer.
【0029】発泡セル19中に形成される誘電体部17
に用いられる材料としては、絶縁性であれば、使用可能
であるが、体積固有抵抗が1012Ω・cm以上、特に1
014Ω・cm以上のものが好ましい。Dielectric part 17 formed in foam cell 19
Any material can be used as long as it has insulating properties, but its volume resistivity is 10 12 Ω · cm or more, especially 1
Those having a value of 0 14 Ω · cm or more are preferable.
【0030】このような絶縁性材料としては、たとえば
ビニル系樹脂、ポリスチレン系樹脂等の有機ポリマー類
が挙げられる。Examples of such insulating materials include organic polymers such as vinyl resins and polystyrene resins.
【0031】導電体部18は、導電性発泡体層から構成
されるが、発泡体を形成する樹脂材料としては、天然ゴ
ム、シリコーンゴム等の有機ポリマー類が使用可能であ
る。The conductor portion 18 is formed of a conductive foam layer. As a resin material forming the foam, organic polymers such as natural rubber and silicone rubber can be used.
【0032】図5の現像ローラを作成するには、例えば
(i)芯金の外周に、ゴム類、導電性付与剤、発泡剤及
びその他の添加剤からなる導電性発泡組成物を押出成形
して弾性発泡体層を設け、ついでその表面を研削して発
泡セルを露出させ、誘電体部埋設用の凹部を成形し、次
に、該凹部に前記誘電体材料20をスプレー、ディッピ
ングなどの方法により埋め込み、所定の条件(温度、時
間)で硬化(焼成)し(塗布膜の厚みは凹部が完全に埋
まる状態にする)〔図6(a)〕、(ii)続いてその表
面を切削又は研磨加工により導電面と誘電面が微小面積
で混在するように削り、導電部面積が20〜60%にな
るように削る〔図6(b)〕という方法が採用される。In order to prepare the developing roller shown in FIG. 5, for example, (i) a conductive foam composition composed of rubbers, a conductivity-imparting agent, a foaming agent and other additives is extrusion-molded on the outer periphery of a cored bar. Then, the elastic foam layer is provided, and the surface thereof is ground to expose the foam cells, a concave portion for embedding the dielectric portion is formed, and then the dielectric material 20 is sprayed and dipped in the concave portion. And cured (fired) under predetermined conditions (temperature and time) (the thickness of the coating film is set so that the concave portion is completely buried) (FIG. 6 (a)), (ii) the surface is subsequently cut or A method is employed in which the conductive surface and the dielectric surface are polished so as to be mixed in a very small area by polishing, and the conductive portion is polished so as to have an area of 20 to 60% (FIG. 6B).
【0033】図7ないし図9に示す現像ローラについ
て、以下に説明する。これらの図に示す現像ローラ1と
して、例えばAl、Fe、Cu等の金属製の導電性ロー
ラ21より成る基体と、その周囲表面に固着された中抵
抗体22及び高抵抗体23とを具備するローラが用いら
れている。中抵抗体22の抵抗率は、導電性の基体表面
(本例では導電性ローラ21)の抵抗率よりも高く、例
えば103乃至108Ω・cm程度に設定され、高抵抗体2
3の抵抗率は、中抵抗体22の抵抗率よりもさらに高
く、例えば109乃至1015Ω・cm程度に設定されてい
る。両抵抗体22,23は、かかる抵抗率を有する誘電
体から構成されているのである。The developing roller shown in FIGS. 7 to 9 will be described below. The developing roller 1 shown in these figures includes a base made of a conductive roller 21 made of a metal such as Al, Fe, Cu, etc., and a medium resistor 22 and a high resistor 23 fixed to the peripheral surface thereof. Rollers are used. The resistivity of the medium resistor 22 is higher than the resistivity of the conductive substrate surface (the conductive roller 21 in this example) and is set to, for example, about 10 3 to 10 8 Ω · cm.
The resistivity of No. 3 is even higher than the resistivity of the medium resistor 22, and is set to, for example, about 10 9 to 10 15 Ω · cm. Both resistors 22 and 23 are made of a dielectric material having such a resistivity.
【0034】図8では、両抵抗体22と23を識別しや
すくするため、高抵抗体23に対して横線を付して示し
てあるが、この図並びに図7および図9から判るよう
に、高抵抗体23と中抵抗体22は規則的に(又は不規
則状態であってもよい)に配置され、これらが現像ロー
ラ1の表面に露出している。In FIG. 8, a horizontal line is shown with respect to the high-resistance element 23 to make it easy to distinguish between the two resistance elements 22 and 23. As can be seen from FIG. 8 and FIGS. The high resistance element 23 and the medium resistance element 22 are arranged regularly (or in an irregular state), and they are exposed on the surface of the developing roller 1.
【0035】各中抵抗体22と高抵抗体23の形状は適
宜設定できるが、その表面形状を図8に例示する如く矩
形とした場合、その一辺の長さD1,D2は、例えば1
0乃至500μm程度の適宜な値に設定することができ
る。このような抵抗体22,23のサイズに関する値や
その抵抗率は、後述する閉電界の強度を高め、現像ロー
ラ1上に最適な量のトナーを担持させることができるよ
うに、適宜選択される。The shape of each of the middle resistor 22 and the high resistor 23 can be appropriately set. When the surface shape is rectangular as illustrated in FIG. 8, the lengths D1 and D2 of one side are, for example, 1
It can be set to an appropriate value of about 0 to 500 μm. The values relating to the sizes of the resistors 22 and 23 and the resistivity thereof are appropriately selected so as to increase the intensity of a closed electric field described later and to carry an optimal amount of toner on the developing roller 1. .
【0036】また本例では、高抵抗体23と中抵抗体2
2として、トナーの帯電極性と反対の極性、すなわち負
極性に摩擦帯電される材質のものが選択されている。In this embodiment, the high resistance element 23 and the medium resistance element 2
As 2, a material having a polarity opposite to the charging polarity of the toner, that is, a material that is frictionally charged to a negative polarity is selected.
【0037】トナー供給ローラ8の周面に接触しながら
現像ローラ1に運ばれるトナー7は、図7に模式的に示
すように、トナー供給ローラ8との摩擦によって正極性
に摩擦帯電され、現像ローラ1に供給されるが、このと
きの現像ローラ1との摩擦によりさらに正極性に強く摩
擦帯電され、現像ローラ1の周面に静電的に付着する。The toner 7 conveyed to the developing roller 1 while being in contact with the peripheral surface of the toner supply roller 8 is frictionally charged to a positive polarity by friction with the toner supply roller 8 as schematically shown in FIG. The toner is supplied to the roller 1, and is frictionally charged to a more positive polarity due to the friction with the developing roller 1 at this time, and electrostatically adheres to the peripheral surface of the developing roller 1.
【0038】このとき、現像ローラ1の高抵抗体23と
中抵抗体22は負極性に摩擦帯電しているが、その抵抗
率が互いに相違するため、図10に模式的に示すよう
に、高抵抗体23の電荷量の方が中抵抗体22の電荷量
よりも多くなり、両者の表面電位に相違が生じる。この
ため、両抵抗体22と23の間には閉電界が形成され
る。At this time, the high-resistance element 23 and the medium-resistance element 22 of the developing roller 1 are triboelectrically charged to the negative polarity. However, since their resistances are different from each other, as shown schematically in FIG. The amount of charge of the resistor 23 is larger than the amount of charge of the middle resistor 22, and a difference occurs between the surface potentials of the two. For this reason, a closed electric field is formed between the two resistors 22 and 23.
【0039】導電性ローラ21の表面には、無数と言え
る程多数の高抵抗体23と中抵抗体22が交互に位置し
ているので、現像ローラ1の表面には無数の微小閉電界
(マイクロフィールド)が現像ローラ表面に一様に分布
した状態で形成される。すなわち、電界の状態を表わす
電気力線を考えた場合、現像ローラ1の表面近傍の空間
には、図10に円弧状の多数の線で表わしたように電気
力線Eが形成され、その電気力線は現像ローラ1から出
て同一の現像ローラ1に戻り、該ローラ1の表面の近傍
に多数の閉電界が形成されるのである。このように、電
界傾度の大なる電界が現像ローラの表面近傍に形成され
る。Since a large number of high-resistance elements 23 and medium-resistance elements 22 are alternately arranged on the surface of the conductive roller 21 so as to be countless, the surface of the developing roller 1 has an infinite number of minute closed electric fields (micro-fields). ) Are uniformly distributed on the surface of the developing roller. That is, when considering the lines of electric force representing the state of the electric field, electric lines of electric force E are formed in the space near the surface of the developing roller 1 as represented by a large number of arc-shaped lines in FIG. The force lines exit the developing roller 1 and return to the same developing roller 1, and a number of closed electric fields are formed near the surface of the roller 1. Thus, an electric field having a large electric field gradient is formed near the surface of the developing roller.
【0040】高抵抗体23と中抵抗体22の表面サイズ
は、前述のように大変微小であるため、各閉電界も微小
なものとなり、これにより各閉電界は所謂エッジ効果な
いしはフリンジング効果(周辺電場効果)によってその
強度が大変強くなる。かかる高強度の閉電界によって、
正に帯電したトナーは、図7に模式的に示したように、
高抵抗体23の表面に強く引かれ、現像ローラ1上に多
量に離れ難い状態で保持される。すなわち、帯電したト
ナーは閉電界の内部に強い束縛力を与えられ、その電気
力線Eに沿って現像ローラ1上に保持されるのである。Since the surface sizes of the high-resistance element 23 and the medium-resistance element 22 are very small as described above, each closed electric field is also very small, so that each closed electric field has a so-called edge effect or fringing effect ( Due to the peripheral electric field effect), the intensity becomes very strong. With such a high intensity closed electric field,
The positively charged toner, as schematically shown in FIG.
It is strongly pulled by the surface of the high resistance element 23 and is held on the developing roller 1 in a state where it is difficult to separate a large amount. That is, the charged toner is given a strong binding force inside the closed electric field, and is held on the developing roller 1 along the line of electric force E.
【0041】その際、トナーはトナー供給ローラ8と現
像ローラ1との摩擦によって強く摩擦帯電しており、し
かも現像ローラ1の表面に強い微小閉電界の作用で保持
されるので、現像ローラ1上には高い電荷を持った多量
のトナーが担持される。しかも、現像ローラ1に担持さ
れたトナーが例えばウレタンよりなるドクターブレード
4によって層厚を規制されるとき、帯電の充分なトナー
は微小閉電界によって現像ローラ1の表面に強く保持さ
れるが、帯電量の小なるトナーがこれに混在していて
も、かかるトナーはドクターブレード4との接触圧によ
って除去され、結局、帯電量の大なるトナーだけが、従
来よりも多量に現像領域へ搬送され、前述の如く静電潜
像を可視像化する。現像領域での現像ローラ1と感光体
1との間の電界は、電極効果が大きくなり、現像ローラ
1上のトナーが感光体ドラム3に付着しやすい状態とな
る。このようにして可視像の画像濃度を高め、かつその
地汚れを防止することができる。At this time, the toner is strongly triboelectrically charged due to the friction between the toner supply roller 8 and the developing roller 1 and is held on the surface of the developing roller 1 by the action of a strong minute electric field. Carries a large amount of toner having a high charge. In addition, when the layer thickness of the toner carried on the developing roller 1 is regulated by a doctor blade 4 made of, for example, urethane, a sufficiently charged toner is strongly held on the surface of the developing roller 1 by a minute closed electric field. Even when a small amount of toner is mixed with the toner, such toner is removed by the contact pressure with the doctor blade 4, and as a result, only the toner having a large charge amount is conveyed to the developing area in a larger amount than before, and The electrostatic latent image is visualized as described above. The electric field between the developing roller 1 and the photoconductor 1 in the developing area has a large electrode effect, so that the toner on the developing roller 1 easily adheres to the photoconductor drum 3. In this manner, the image density of the visible image can be increased and the background can be prevented from being stained.
【0042】図11および図12において、現像ローラ
1は抵抗又は誘電率の異なる複数の材料で構成されてい
る。すなわち、同現像ローラは、導電性材料、例えばア
ルミニウム等の金属素材あるいは導電性ゴムや導電性プ
ラスチックのローラの表面に網目状ローレット加工を施
し、その条痕にポリカーボネート、アクリル、ポリエス
テル、4弗化エチレン等の誘電体樹脂を摺り込んで充て
んし、微細な網目状の絶縁性領域面25を形成すると共
に、これに接して微細な導電性領域面24を形成してい
る。In FIGS. 11 and 12, the developing roller 1 is made of a plurality of materials having different resistances or dielectric constants. That is, the developing roller is formed by applying a mesh-like knurling process to the surface of a roller made of a conductive material, for example, a metal material such as aluminum, or a conductive rubber or a conductive plastic, and applying a polycarbonate, acryl, polyester, or tetrafluoride to the streaks. A dielectric resin such as ethylene is rubbed and filled to form a fine mesh-shaped insulating region surface 25, and a fine conductive region surface 24 is formed in contact therewith.
【0043】微細な導電性領域面24と絶縁性領域面2
5を形成する方法は上記の例に限られるものではなく、
各種の方法が採用可能である。Fine conductive region surface 24 and insulating region surface 2
The method of forming 5 is not limited to the above example,
Various methods can be adopted.
【0044】絶縁性領域の大きさは平均直径として30
〜2000μm、好ましくは50〜1000μmであ
る。絶縁性領域面25の形状が例えば円形であるとき
は、図13に示すように、その径D1を30乃至200
0μm、好ましくは100乃至400μm程度に設定
し、その中心間距離P1を、適宜バランス良く設定す
る。又絶縁性領域面25の形状が矩形であるときは、こ
の一番短い辺の長さを30乃至2000μm程度とす
る。同様に、絶縁性領域面25の形状が長円形乃至は楕
円形であるときは、その短軸側の幅を30乃至2000
μm程度とする。絶縁性領域面25の形状が他の形状の
ときも、これらに準じて、その幅を30乃至2000μ
m程度とする。又、その占有面積比率としては、現像ロ
ーラ1表面積の50〜80%、好ましくは65〜75%
とすれば良い。現像ローラ1の構造をこのようにするこ
とによって、トナー供給ローラ8でトナー7を現像ロー
ラ1にこすりつける時に生ずる摩擦帯電作用によりトナ
ー7を帯電して、現像ローラ1の表面に充分な量のトナ
ーを担持することが出来る。The size of the insulating region is 30 as an average diameter.
20002000 μm, preferably 50-1000 μm. When the shape of the insulating region surface 25 is, for example, a circle, as shown in FIG.
The distance is set to 0 μm, preferably about 100 to 400 μm, and the center-to-center distance P1 is appropriately set in a well-balanced manner. When the shape of the insulating region surface 25 is rectangular, the length of the shortest side is about 30 to 2000 μm. Similarly, when the shape of the insulating region surface 25 is an ellipse or an ellipse, the width on the minor axis side is 30 to 2000.
It is about μm. When the shape of the insulating region surface 25 is another shape, the width is set to 30 to 2000 μm according to these.
m. The occupied area ratio is 50 to 80%, preferably 65 to 75% of the surface area of the developing roller 1.
It is good. By making the structure of the developing roller 1 in this manner, the toner 7 is charged by the frictional charging effect generated when the toner 7 is rubbed against the developing roller 1 by the toner supply roller 8, and a sufficient amount of the toner 7 is applied to the surface of the developing roller 1. It can carry toner.
【0045】[0045]
【発明の効果】現像ローラのトナー付着量およびトナー
帯電量を改善し、更にトナーの付着力を弱めて現像転移
率を高めることにより、階調度がよくかつ高濃度の画像
を得ることが出来る。As described above, by improving the toner adhesion amount and the toner charge amount of the developing roller, and further increasing the development transfer rate by weakening the toner adhesion force, it is possible to obtain an image with good gradation and high density.
【図1】図1は本発明を適用せる現像装置の断面図であ
る。FIG. 1 is a sectional view of a developing device to which the present invention is applied.
【図2】図2は重畳印加電圧波形を示す図である。FIG. 2 is a diagram showing a superimposed applied voltage waveform.
【図3】図3は現像ローラにおける閉電界生成の説明図
である。FIG. 3 is an explanatory diagram of generation of a closed electric field in a developing roller.
【図4】図4は別の構成の現像ローラの部分断面図であ
る。FIG. 4 is a partial cross-sectional view of a developing roller having another configuration.
【図5】図5は誘電体部を発泡セル中に形成した現像ロ
ーラの説明図である。FIG. 5 is an explanatory diagram of a developing roller in which a dielectric portion is formed in a foam cell.
【図6】図6は図5に示す現像ローラの作成過程を示す
図式断面図である。FIG. 6 is a schematic cross-sectional view showing a process of producing the developing roller shown in FIG.
【図7】図7は更に別の構成の現像ローラを示す説明図
である。FIG. 7 is an explanatory view showing a developing roller having still another configuration.
【図8】図8は各抵抗体を模式的に示す現像ローラ表面
の1部の拡大平面図である。FIG. 8 is an enlarged plan view of a part of the surface of a developing roller schematically showing each resistor.
【図9】図9は図8のIV−IV線による断面図である。FIG. 9 is a sectional view taken along line IV-IV in FIG.
【図10】図10は図8および図9に示す現像ローラ表
面に形成される微小閉電界の電気力線を示す説明図であ
る。FIG. 10 is an explanatory diagram showing electric lines of force of a minute closed electric field formed on the surface of the developing roller shown in FIGS. 8 and 9;
【図11】図11は更に別の構成の現像ローラの斜視図
である。FIG. 11 is a perspective view of a developing roller having still another configuration.
【図12】図12は図11に示す現像ローラの1部の断
面図である。FIG. 12 is a sectional view of a part of the developing roller shown in FIG. 11;
【図13】図13は図11に示す現像ローラの表面に形
成される微小閉電界の電気力線を示す説明図である。FIG. 13 is an explanatory diagram showing electric lines of force of a minute closed electric field formed on the surface of the developing roller shown in FIG. 11;
1 現像ローラ 2 現像装置 3 感光体ドラム 7 トナー 9 低周波交互電圧印加用電源 10 高周波交互電圧印加用電源 11,17 誘電体部 12,18 導電体部 13 閉電界 19 発泡セル 22 中抵抗体 23 高抵抗体 24 導電性領域面 25 絶縁性領域面 DESCRIPTION OF SYMBOLS 1 Developing roller 2 Developing device 3 Photoreceptor drum 7 Toner 9 Power supply for low frequency alternating voltage application 10 Power supply for high frequency alternating voltage application 11, 17 Dielectric part 12, 18 Conductor part 13 Closed electric field 19 Foaming cell 22 Medium resistor 23 High resistance body 24 Conductive area surface 25 Insulating area surface
───────────────────────────────────────────────────── フロントページの続き (72)発明者 榎木 繁和 東京都大田区中馬込1丁目3番6号 株 式会社リコー内 (72)発明者 冨田 潤子 東京都大田区中馬込1丁目3番6号 株 式会社リコー内 (56)参考文献 特開 昭61−273563(JP,A) 特開 平2−61652(JP,A) 特開 平1−267566(JP,A) 特開 昭60−61774(JP,A) 実開 昭60−54150(JP,U) 実開 昭62−79257(JP,U) (58)調査した分野(Int.Cl.7,DB名) G03G 15/06 G03G 15/08 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shigekazu Enoki 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (72) Inventor Junko Tomita 1-3-6 Nakamagome, Ota-ku, Tokyo No. Ricoh Co., Ltd. (56) References JP-A-61-273563 (JP, A) JP-A-2-61652 (JP, A) JP-A-1-267566 (JP, A) JP-A-60-61774 (JP, A) Japanese Utility Model Showa 60-54150 (JP, U) Japanese Utility Model Showa 62-79257 (JP, U) (58) Fields investigated (Int. Cl. 7 , DB name) G03G 15/06 G03G 15 / 08
Claims (14)
剤を担持した現像剤担持体とを現像部において対向さ
せ、現像部においてバイアスを印加して現像を行う現像
装置において、導電性基体の表面に該基体の導電部と基
体に固着された誘電部とが規則的または不規則に混在露
出してなるとともに、少なくとも前記誘電部を現像剤の
極性と逆極性または同極性に帯電することにより表面に
多数の微小閉電界を形成する現像剤担持体と、第1交互
電界と第1交互電界より高周波の第2交互電界を重畳し
た交互電界を形成するバイアスを印加する手段とを有
し、前記現像部にて、前記静電潜像担持体上の電位と前
記バイアスによる電界と前記現像剤担持体上の微小閉電
界とにより決定される電界により、前記現像剤担持体に
保持された前記現像剤の前記静電潜像担持体への転移、
逆転移を行って現像することを特徴とする現像装置。An image forming apparatus includes an electrostatic latent image carrier that carries an electrostatic latent image and a developer carrier that carries a developer in a developing unit, and a bias is applied to the developing unit to perform development. The conductive portion of the substrate and the dielectric portion fixed to the substrate are regularly or irregularly mixed and exposed on the surface of the conductive substrate, and at least the dielectric portion is made of a developer.
A developer carrying member that forms a large number of minute closed electric fields on the surface by being charged to the opposite polarity or the same polarity as the polarity, and an alternating electric field obtained by superimposing a first alternating electric field and a second alternating electric field having a higher frequency than the first alternating electric field. Means for applying a bias to be formed, wherein in the developing section, the potential on the electrostatic latent image carrier, the electric field due to the bias, and the minute closing on the developer carrier
The developer carrier by the electric field determined by the
Transfer of the held developer to the electrostatic latent image carrier,
A developing device characterized by performing reverse transfer and developing.
剤を担持した現像剤担持体とを現像部において対向さ
せ、現像部においてバイアスを印加して現像を行う現像
装置において、抵抗または誘電率の異なる複数の材料が
規則的または不規則に混在露出してなるとともに、少な
くとも前記抵抗または誘電率の異なる複数の材料を現像
剤の極性と逆極性または同極性に帯電することにより表
面に多数の微小閉電界を形成する現像剤担持体と、第1
交互電界と第1交互電界より高周波の第2交互電界を重
畳した交互電界を形成するバイアスを印加する手段とを
有し、前記現像部にて、前記静電潜像担持体上の電位と
前記バイアスによる電界と前記現像剤担持体上の微小閉
電界とにより決定される電界により、前記現像剤担持体
に保持された前記現像剤の前記静電潜像担持体への転
移、逆転移を行って現像することを特徴とする現像装
置。2. A developing device, comprising: an electrostatic latent image carrier for carrying an electrostatic latent image and a developer carrier for carrying a developer facing each other in a developing section; , together with the different material is mixed exposed regularly or irregularly resistivity or dielectric constant, low
Develop at least several materials with different resistance or dielectric constant
A developer carrier that forms a large number of minute closed electric fields on the surface by being charged to a polarity opposite to or the same as the polarity of the developer;
And means for applying a bias to form an alternating electric field and alternating electric field superimposing the second alternating field of high frequency than the first alternating electric field at the developing unit, the potential on the latent electrostatic image bearing member Electric field due to bias and micro-close on the developer carrier
An electric field determined by the electric field and the developer carrier
Transfer of the developer held on the electrostatic latent image carrier to the developer
A developing device for performing development by performing transfer and reverse transfer .
剤を担持した現像剤担持体とを現像部において対向さ
せ、現像部においてバイアスを印加して現像を行う現像
装置において、絶縁性粒子を含有した導電材料を成型し
てなるとともに、少なくとも前記絶縁性粒子を現像剤の
極性と逆極性または同極性に帯電することにより表面に
多数の微小閉電界を形成する現像剤担持体と、第1交互
電界と第1交互電界より高周波の第2交互電界を重畳し
た交互電界を形成するバイアスを印加する手段とを有
し、前記現像部にて、前記静電潜像担持体上の電位と前
記バイアスによる電界と前記現像剤担持体上の微小閉電
界とにより決定される電界により、前記現像剤担持体に
保持された前記現像剤の前記静電潜像担持体への転移、
逆転移を行って現像することを特徴とする現像装置。3. A developing device in which an electrostatic latent image carrier carrying an electrostatic latent image and a developer carrier carrying a developer are opposed in a developing section, and a bias is applied in the developing section to perform development. Along with molding a conductive material containing insulating particles, at least the insulating particles
A developer carrying member that forms a large number of minute closed electric fields on the surface by being charged to the opposite polarity or the same polarity as the polarity, and an alternating electric field obtained by superimposing a first alternating electric field and a second alternating electric field having a higher frequency than the first alternating electric field. Means for applying a bias to be formed, wherein in the developing section, the potential on the electrostatic latent image carrier, the electric field due to the bias, and the minute closing on the developer carrier
The developer carrier by the electric field determined by the
Transfer of the held developer to the electrostatic latent image carrier,
A developing device characterized by performing reverse transfer and developing.
剤を担持した現像剤担持体とを現像部において対向さ
せ、現像部においてバイアスを印加して現像を行う現像
装置において、表面に導電体部と誘電体部とが微小面積
で混在してなり、かつ該誘電体部は導電性発泡体層の表
面近傍の発泡セル中に形成されたものを用いるととも
に、少なくとも誘電体部が現像剤の極性と逆極性または
同極性に帯電することにより表面に多数の微小閉電界を
形成する現像剤担持体と、第1交互電界と第1交互電界
より高周波の第2交互電界を重畳した交互電界を形成す
るバイアスを印加する手段とを有し、前記現像部にて、
前記静電潜像担持体上の電位と前記バイアスによる電界
と前記現像剤担持体上の微小閉電界とにより決定される
電界により、前記現像剤担持体に保持された前記現像剤
の前記静電潜像担持体への転移、逆転移を行って現像す
ることを特徴とする現像装置。4. A developing device in which an electrostatic latent image carrier carrying an electrostatic latent image and a developer carrier carrying a developer are opposed to each other in a developing section, and a bias is applied in the developing section to perform development. A conductive part and a dielectric part are mixed in a minute area on the surface, and the dielectric part is formed in a foam cell near the surface of the conductive foam layer. A developer carrier that forms a large number of micro-closed electric fields on the surface when the portion is charged to a polarity opposite or the same as the polarity of the developer; and a first alternating electric field and a second alternating electric field having a higher frequency than the first alternating electric field. Means for applying a bias for forming a superimposed alternating electric field ,
Determined by the potential on the electrostatic latent image carrier, the electric field due to the bias, and the minute closed electric field on the developer carrier
The developer held on the developer carrier by an electric field
Transfer to the electrostatic latent image carrier, reverse transfer and development
Developing apparatus is characterized in that that.
剤を担持した現像剤担持体とを現像部において対向さ
せ、現像部においてバイアスを印加して現像を行う現像
装置において、表面に導電体部と誘電体部とが微小面積
で混在してなりかつこれらが絶縁性粒子を含有した弾性
導電性材料からなるものを用いるとともに、少なくとも
誘電体部が現像剤の極性と逆極性または同極性に帯電す
ることにより表面に多数の微小閉電界を形成する現像剤
担持体と、第1交互電界と第1交互電界より高周波の第
2交互電界を重畳した交互電界を形成するバイアスを印
加する手段とを有し、前記現像部にて、前記静電潜像担
持体上の電位と前記バイアスによる電界と前記現像剤担
持体上の微小閉電界とにより決定される電界により、前
記現像剤担持体に保持された前記現像剤の前記静電潜像
担持体への転移、逆転移を行って現像することを特徴と
する現像装置。5. A developing device in which an electrostatic latent image carrier for carrying an electrostatic latent image and a developer carrier for carrying a developer are opposed in a developing section, and a bias is applied in the developing section to perform development. In addition, a conductive part and a dielectric part are mixed in a minute area on the surface and made of an elastic conductive material containing insulating particles, and at least the dielectric part has a polarity opposite to that of the developer. A developer carrier that forms a large number of minute closed electric fields on the surface by being charged to a polarity or the same polarity, and a bias that forms an alternating electric field in which a first alternating electric field and a second alternating electric field higher in frequency than the first alternating electric field are superimposed; and means for applying said at developing unit, by an electric field determined by a micro閉電field on field and said developer carrying member by electric potential and the bias on the electrostatic latent image bearing member, before
The electrostatic latent image of the developer held on the developer carrier
A developing device for performing development by performing transfer to a carrier and reverse transfer .
体部とが微小面積で混在してなり、かつこれらが弾性絶
縁性粒子を含有した弾性導電性材料からなるものを用い
るとともに、少なくとも誘電体部が現像剤の極性と逆極
性または同極性に帯電することにより表面に多数の微小
閉電界を形成する請求項5に記載の現像装置。 6. A developer carrier comprising a conductive part and a dielectric part mixed on a surface thereof in a very small area, each of which is made of an elastic conductive material containing elastic insulating particles. , At least the dielectric part is charged to the opposite polarity or the same polarity as the polarity of the developer, so that many minute
The developing device according to claim 5, which forms a closed electric field .
担持体に保持されることを特徴とする請求項1乃至請求
項6いずれかに記載の現像装置。7. Before Symbol developing device according to any one claims 1 to 6, characterized in that it is held to the developer carrying member developer by the micro閉電field.
剤を担持した現像剤担持体とを現像部において対向さ
せ、現像部においてバイアスを印加して現像を行う現像
装置において、導電性基体の表面に該基体の導電部と基
体に固着された誘電部とが規則的または不規則に混在露
出してなるとともに、少なくとも前記誘電部を現像剤の
極性と逆極性または同極性に帯電することにより表面に
多数の微小閉電界を形成する現像剤担持体と、第1工程
として第1交互電界を形成するバイアスを印加する手段
と、第2工程として第1交互電界より小さい交互電界と
第1交互電界より高周波の第2交互電界を重畳した交互
電界を形成するバイアスを印加する手段とを有し、前記
現像部にて、前記静電潜像担持体上の電位と前記バイア
スによる電界と前記現像剤担持体上の微小閉電界とによ
り決定される電界により、前記現像剤担持体に保持され
た前記現像剤の前記静電潜像担持体への転移、逆転移を
行って現像することを特徴とする現像装置。8. A developing device for developing an electrostatic latent image bearing member carrying an electrostatic latent image and a developer carrying member carrying a developer in a developing portion by applying a bias in the developing portion. The conductive portion of the substrate and the dielectric portion fixed to the substrate are regularly or irregularly mixed and exposed on the surface of the conductive substrate, and at least the dielectric portion is made of a developer.
A developer carrying member that forms a large number of minute closed electric fields on the surface by being charged to the opposite polarity or the same polarity as the polarity ; a means for applying a bias for forming a first alternating electric field as a first step; and means for applying a bias for forming an alternating electric field by superimposing a second alternating electric field of high frequency smaller alternating electric field and a first alternating electric field from the first alternating electric field, the
In the developing unit, the potential on the electrostatic latent image carrier, the electric field due to the bias, and the minute closed electric field on the developer carrier are used .
Is held by the developer carrier by the electric field determined
Transfer of the developer to the electrostatic latent image carrier,
Developing apparatus characterized by development performed.
剤を担持した現像剤担持体とを現像部において対向さ
せ、現像部においてバイアスを印加して現像を行う現像
装置において、抵抗または誘電率の異なる複数の材料が
規則的または不規則に混在露出してなるとともに、少な
くとも前記抵抗または誘電率の異なる複数の材料を現像
剤の極性と逆極性または同極性に帯電することにより表
面に多数の微小閉電界を形成する現像剤担持体と、第1
工程として第1交互電界を形成するバイアスを印加する
手段と、第2工程として第1交互電界より小さい交互電
界と第1交互電界より高周波の第2交互電界を重畳した
交互電界を形成するバイアスを印加する手段とを有し、
前記現像部にて、前記静電潜像担持体上の電位と前記バ
イアスによる電界と前記現像剤担持体上の微小閉電界と
により決定される電界により、前記現像剤担持体に保持
された前記現像剤の前記静電潜像担持体への転移、逆転
移を行って現像することを特徴とする現像装置。9. A developing device in which an electrostatic latent image carrier for carrying an electrostatic latent image and a developer carrier for carrying a developer are opposed in a developing section, and a bias is applied in the developing section to perform development. , together with the different material is mixed exposed regularly or irregularly resistivity or dielectric constant, low
Develop at least several materials with different resistance or dielectric constant
A developer carrier that forms a large number of minute closed electric fields on the surface by being charged to a polarity opposite to or the same as the polarity of the developer;
A means for applying a bias for forming a first alternating electric field as a step, and a bias for forming an alternating electric field in which an alternating electric field smaller than the first alternating electric field and a second alternating electric field higher in frequency than the first alternating electric field are superimposed as a second step. Means for applying,
In the developing unit, an electric field due to the potential and the bias on the electrostatic latent image carrier and a minute closed electric field on the developer carrier
Held on the developer carrier by the electric field determined by
Transfer, reversal of the developed developer to the electrostatic latent image carrier
A developing device for performing transfer and developing.
像剤を担持した現像剤担持体とを現像部において対向さ
せ、現像部においてバイアスを印加して現像を行う現像
装置において、絶縁性粒子を含有した導電材料を成型し
てなるとともに、少なくとも前記絶縁性粒子を現像剤の
極性と逆極性または同極性に帯電することにより表面に
多数の微小閉電界を形成する現像剤担持体と、第1工程
として第1交互電界を形成するバイアスを印加する手段
と、第2工程として第1交互電界より小さい交互電界と
第1交互電界より高周波の第2交互電界を重畳した交互
電界を形成するバイアスを印加する手段とを有し、前記
現像部にて、前記静電潜像担持体上の電位と前記バイア
スによる電界と前記現像剤担持体上の微小閉電界とによ
り決定される電界により、前記現像剤担持体に保持され
た前記現像剤の前記静電潜像担持体への転移、逆転移を
行って現像することを特徴とする現像装置。10. A developing device in which an electrostatic latent image carrier for carrying an electrostatic latent image and a developer carrier for carrying a developer are opposed in a developing section, and a bias is applied in the developing section to perform development. Along with molding a conductive material containing insulating particles, at least the insulating particles
A developer carrying member that forms a large number of minute closed electric fields on the surface by being charged to the opposite polarity or the same polarity as the polarity ; a means for applying a bias for forming a first alternating electric field as a first step; and means for applying a bias for forming an alternating electric field by superimposing a second alternating electric field of high frequency smaller alternating electric field and a first alternating electric field from the first alternating electric field, the
In the developing unit, the potential on the electrostatic latent image carrier, the electric field due to the bias, and the minute closed electric field on the developer carrier are used .
Is held by the developer carrier by the electric field determined
Transfer of the developer to the electrostatic latent image carrier,
Developing apparatus characterized by development performed.
像剤を担持した現像剤担持体とを現像部において対向さ
せ、現像部においてバイアスを印加して現像を行う現像
装置において、表面に導電体部と誘電体部とが微小面積
で混在してなり、かつ該誘電体部は導電性発泡体層の表
面近傍の発泡セル中に形成されたものを用いるととも
に、少なくとも誘電体部が現像剤の極性と逆極性または
同極性に帯電することにより表面に多数の微小閉電界を
形成する現像剤担持体と、第1工程として第1交互電界
を形成するバイアスを印加する手段と、第2工程として
第1交互電界より小さい交互電界と第1交互電界より高
周波の第2交互電界を重畳した交互電界を形成するバイ
アスを印加する手段とを有し、前記現像部にて、前記静
電潜像担持体上の電位と前記バイアスによる電界と前記
現像剤担持体上の微小閉電界とにより決定される電界に
より、前記現像剤担持体に保持された前記現像剤の前記
静電潜像担持体への転移、逆転移を行って現像すること
を特徴とする現像装置。11. A developing device in which an electrostatic latent image carrier for carrying an electrostatic latent image and a developer carrier for carrying a developer are opposed in a developing section, and a bias is applied in the developing section to perform development. A conductive part and a dielectric part are mixed in a minute area on the surface, and the dielectric part is formed in a foam cell near the surface of the conductive foam layer. A developer carrying member that forms a large number of micro-closed electric fields on the surface by charging the part with a polarity opposite to or the same as the polarity of the developer; and a unit that applies a bias that forms a first alternating electric field as a first step. , and means for applying a bias for forming a smaller alternating electric field than the first alternating electric field as a second step alternating electric field superimposing the second alternating field of high frequency than the first alternating electric field at the developing unit, the The charge on the electrostatic latent image carrier The electric field is determined by the electric field and the micro閉電field on the developer carrying member by the bias and
From the above, the developer of the developer held by the developer carrier
A developing device for performing development by performing transfer to an electrostatic latent image carrier and reverse transfer .
像剤を担持した現像剤担持体とを現像部において対向さ
せ、現像部においてバイアスを印加して現像を行う現像
装置において、表面に導電体部と誘電体部とが微小面積
で混在してなりかつこれらが絶縁性粒子を含有した弾性
導電性材料からなるものを用いるとともに、少なくとも
誘電体部が現像剤の極性と逆極性または同極性に帯電す
ることにより表面に多数の微小閉電界を形成する現像剤
担持体と、第1工程として第1交互電界を形成するバイ
アスを印加する手段と、第2工程として第1交互電界よ
り小さい交互電界と第1交互電界より高周波の第2交互
電界を重畳した交互電界を形成するバイアスを印加する
手段とを有し、前記現像部にて、前記静電潜像担持体上
の電位と前記バイアスによる電界と前記現像剤担持体上
の微小閉電界とにより決定される電界により、前記現像
剤担持体に保持された前記現像剤の前記静電潜像担持体
への転移、逆転移を行って現像することを特徴とする現
像装置。12. A developing device in which an electrostatic latent image carrier for carrying an electrostatic latent image and a developer carrier for carrying a developer are opposed in a developing section, and a bias is applied in the developing section to perform development. In addition, a conductive part and a dielectric part are mixed in a minute area on the surface and made of an elastic conductive material containing insulating particles, and at least the dielectric part has a polarity opposite to that of the developer. A developer carrier that forms a large number of minute closed electric fields on the surface by being charged to the same polarity or the same polarity; a unit that applies a bias that forms a first alternating electric field as a first step; and means for applying a bias for forming an alternating electric field superimposed with smaller alternating electric field and a second alternating electric field of high frequency than the first alternating electric field electric field at the developing section, on the latent electrostatic image bearing member Potential and said bi The electric field is determined by the by scan the field and the minute閉電field on the developer carrying member, said developing
Electrostatic latent image carrier of the developer held by developer carrier
A developing device, which performs development by performing transfer to a reverse transfer and reverse transfer .
電体部とが微小面積で混在してなり、かつこれらが弾性
絶縁性粒子を含有した弾性導電性材料からなるものを用
いるとともに、少なくとも誘電体部が現像剤の極性と逆
極性または同極性に帯電することにより表面に多数の微
小閉電界を形成する請求項12に記載の現像装置。13. A developer carrier comprising a conductive part and a dielectric part mixed on a surface with a very small area on the surface and made of an elastic conductive material containing elastic insulating particles. At least the dielectric portion is charged to a polarity opposite to or the same as the polarity of the developer, so that a large number of fine particles are formed on the surface.
The developing device according to claim 12, wherein the developing device forms a small closed electric field .
剤担持体に保持されることを特徴とする請求項8乃至請
求項13のいずれかに記載の現像装置。14. The developing device according to claim 8, wherein the developer is held on the developer carrier by the minute closed electric field .
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP03080116A JP3080426B2 (en) | 1991-04-12 | 1991-04-12 | Developing device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP03080116A JP3080426B2 (en) | 1991-04-12 | 1991-04-12 | Developing device |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH04314068A JPH04314068A (en) | 1992-11-05 |
JP3080426B2 true JP3080426B2 (en) | 2000-08-28 |
Family
ID=13709225
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP03080116A Expired - Lifetime JP3080426B2 (en) | 1991-04-12 | 1991-04-12 | Developing device |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP3080426B2 (en) |
-
1991
- 1991-04-12 JP JP03080116A patent/JP3080426B2/en not_active Expired - Lifetime
Also Published As
Publication number | Publication date |
---|---|
JPH04314068A (en) | 1992-11-05 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP3243696B2 (en) | Developing device | |
US5220383A (en) | Developing device for an image forming apparatus having a large number of microfields formed on a developer carrier | |
JP3080426B2 (en) | Developing device | |
JP3086000B2 (en) | Developing device | |
JP3029138B2 (en) | Developing device | |
JP3024711B2 (en) | Developing device | |
JP3147922B2 (en) | Developing method and apparatus | |
JP3049622B2 (en) | Developing device | |
JP3035638B2 (en) | Image forming device | |
JP3078349B2 (en) | Developing device | |
JP3151228B2 (en) | Developing device | |
JP3078345B2 (en) | Developing device | |
JP3151231B2 (en) | Developing device | |
JP3078337B2 (en) | Developing method and apparatus | |
JPH04127177A (en) | Developing method and device | |
JP3078347B2 (en) | Developing device | |
JP3272126B2 (en) | One-component developing device | |
JP3020644B2 (en) | Developing device | |
JP3020641B2 (en) | Developing device | |
JP3897085B2 (en) | Image forming apparatus | |
JP3049620B2 (en) | Developing device | |
JP3078348B2 (en) | Developing method and apparatus | |
JP3078346B2 (en) | Developing method and apparatus | |
JP3080423B2 (en) | One-component developing device | |
JP3049621B2 (en) | Developing device |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080623 Year of fee payment: 8 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090623 Year of fee payment: 9 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090623 Year of fee payment: 9 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100623 Year of fee payment: 10 |