JPS62192758A - Developing method - Google Patents
Developing methodInfo
- Publication number
- JPS62192758A JPS62192758A JP3546086A JP3546086A JPS62192758A JP S62192758 A JPS62192758 A JP S62192758A JP 3546086 A JP3546086 A JP 3546086A JP 3546086 A JP3546086 A JP 3546086A JP S62192758 A JPS62192758 A JP S62192758A
- Authority
- JP
- Japan
- Prior art keywords
- toner
- sleeve
- magnetic particles
- latent image
- electric field
- 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
- 238000000034 method Methods 0.000 title claims description 18
- 239000006249 magnetic particle Substances 0.000 claims abstract description 95
- 230000005684 electric field Effects 0.000 claims abstract description 45
- 239000002245 particle Substances 0.000 claims abstract description 28
- 210000005069 ears Anatomy 0.000 description 27
- 239000010410 layer Substances 0.000 description 20
- 108091008695 photoreceptors Proteins 0.000 description 11
- 230000000694 effects Effects 0.000 description 8
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 5
- 229910052782 aluminium Inorganic materials 0.000 description 5
- 239000000696 magnetic material Substances 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- 230000007423 decrease Effects 0.000 description 4
- 238000010408 sweeping Methods 0.000 description 4
- 230000009471 action Effects 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 239000004020 conductor Substances 0.000 description 2
- 238000007599 discharging Methods 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 229910001369 Brass Inorganic materials 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 239000004793 Polystyrene Substances 0.000 description 1
- 239000006061 abrasive grain Substances 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 230000001174 ascending effect Effects 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 239000010951 brass Substances 0.000 description 1
- 238000005282 brightening Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000011247 coating layer Substances 0.000 description 1
- 239000008119 colloidal silica Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 238000009499 grossing Methods 0.000 description 1
- RBTKNAXYKSUFRK-UHFFFAOYSA-N heliogen blue Chemical compound [Cu].[N-]1C2=C(C=CC=C3)C3=C1N=C([N-]1)C3=CC=CC=C3C1=NC([N-]1)=C(C=CC=C3)C3=C1N=C([N-]1)C3=CC=CC=C3C1=N2 RBTKNAXYKSUFRK-UHFFFAOYSA-N 0.000 description 1
- 230000005389 magnetism Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 239000000123 paper Substances 0.000 description 1
- 239000000049 pigment Substances 0.000 description 1
- 229920002223 polystyrene Polymers 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 230000000452 restraining effect Effects 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000005488 sandblasting Methods 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
- 229920003048 styrene butadiene rubber Polymers 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 229920003002 synthetic resin Polymers 0.000 description 1
- 239000000057 synthetic resin Substances 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
Landscapes
- Magnetic Brush Developing In Electrophotography (AREA)
- Developing For Electrophotography (AREA)
Abstract
Description
【発明の詳細な説明】
(産業上の利用分舒)
本発明は電子写真法あるいは静電記録法などによって形
成された静電潜像を現像する現像方法に関する。DETAILED DESCRIPTION OF THE INVENTION (Industrial Application) The present invention relates to a developing method for developing an electrostatic latent image formed by electrophotography or electrostatic recording.
(背景技術)
出願人は、現像剤の薄層を現像剤担持体上に形成し、該
薄層の現像剤を潜像に接近させ、この接近部分に交互電
界を印加して現像を行なう現像装置を提案した(特公昭
58−32375号、同58−32377号明細書)。(Background Art) The applicant has proposed a development method in which a thin layer of developer is formed on a developer carrier, the developer in the thin layer is brought close to a latent image, and an alternating electric field is applied to this approaching portion to perform development. proposed a device (Japanese Patent Publication Nos. 58-32375 and 58-32377).
この装置は現像効率(現像部に存在するトナーのうち現
像に消費され得るトナーの割合)が高く、小型化などの
面で非常に有用であるが、この装置において使用される
現像剤は一成分磁性トナーであるために、トナーは磁性
材を含有することが必須であり、このため現像像の定着
性が悪いこと、またカラー画像の再現製が悪いこと、な
どの欠点を有する。This device has a high development efficiency (the ratio of toner that can be consumed for development out of the toner present in the development section) and is very useful in terms of miniaturization. However, the developer used in this device is one component. Since the toner is a magnetic toner, it is essential that the toner contains a magnetic material, which has drawbacks such as poor fixability of developed images and poor reproduction of color images.
この欠点を補う装置として出願人は、非磁性トナーを使
用し、非磁性トナーのみの薄層を現像剤担持部材上に形
成する方法および装置を開発し、非磁性トナーのみの薄
層を潜像に対面させて交互電界を印加して現像を行なう
現像方法および装置を提案した(特開昭58−1433
60号、同59−101880号明細書)。As a device to compensate for this drawback, the applicant has developed a method and device that uses non-magnetic toner to form a thin layer of only non-magnetic toner on a developer carrying member, and forms a latent image of the thin layer of only non-magnetic toner. proposed a developing method and apparatus in which development is carried out by applying an alternating electric field to the two faces (Japanese Patent Laid-Open No. 58-1433).
No. 60, specification No. 59-101880).
これは、前記の磁性トナーを使用する現像装置の利点を
保ちつつ、トナーが磁性材料を含有することによる欠点
を解消したので有用であるが、現像像の濃度が比較的低
いことおよび後述の負性特性(画像濃度が潜像電位の上
昇とともに低下すること)を示す場合があるなどの現像
特性の欠点が見出された。This is useful because it eliminates the disadvantages caused by the toner containing magnetic materials while maintaining the advantages of the developing device using magnetic toner, but it also has the disadvantages of relatively low density of the developed image and the negative effects described below. It has been found that there are some drawbacks in the development characteristics, such as the fact that the image density may decrease as the latent image potential increases.
また、いわゆる2成分磁気ブラシ現像法として知られて
いるもの(例えば、特開昭53−93841号明細書)
は、非磁性現像剤を使用できるが、現像部における磁気
ブラシ中の消費可能なトナーの割合が少ないので現像効
率が低い、ブラシによる摺擦の跡が掃目のように現像像
に発生するなどの欠点がある。Also, what is known as the so-called two-component magnetic brush development method (for example, Japanese Patent Application Laid-open No. 53-93841)
A non-magnetic developer can be used, but the development efficiency is low because the proportion of consumable toner in the magnetic brush in the developing section is low, and scratches caused by the brush may appear on the developed image, like sweeping marks. There are drawbacks.
(発明の目的)
したがって、本発明は現像効率が高く、高画像濃度の現
像像を形成することができ、しかも負性特性がない現像
方法を提供することを目的とする。(Objective of the Invention) Therefore, an object of the present invention is to provide a developing method that has high developing efficiency, can form a developed image with high image density, and has no negative characteristics.
(発明の概要)
本発明は、現像剤担持体上にトナー粒子層とトナー粒子
と磁性粒子からなる磁気ブラシ層を持ち、該現像剤担持
体と該静電潜像担持体との間に交流成分と直流成分から
なるバイアス電界を印加して現像する現像方法において
、前記交流成分の電界を周波数200〜3000Hzと
し、ピークトウピーク電圧を静電潜像を破壊せず、かつ
現像領域において磁性粒子を前記現像剤担持体と前記静
’21Hu像間を移動させる電圧とすることを特徴とす
る現像方法である。(Summary of the Invention) The present invention has a toner particle layer and a magnetic brush layer made of toner particles and magnetic particles on a developer carrier, and an alternating current between the developer carrier and the electrostatic latent image carrier. In a developing method in which development is performed by applying a bias electric field consisting of a DC component and a DC component, the electric field of the AC component has a frequency of 200 to 3000 Hz, and the peak-to-peak voltage is set such that the electrostatic latent image is not destroyed and the magnetic particles are not damaged in the development area. The developing method is characterized in that the voltage is set to move between the developer carrier and the static '21Hu image.
(実施例)
第1図は本発明の実施例による現像装置の断面図である
。(Embodiment) FIG. 1 is a sectional view of a developing device according to an embodiment of the present invention.
本図において、1は像されるべき静電潜像を担持する静
電潜像担持体であり、具体的には無端移動可能な感光ド
ラムあるいはベルトもしくは誘電体ドラムあるいはベル
トなどである。この上に静電潜像を形成する方法は本発
明の要旨ではなく、公知の方法でよい。本実施例では静
電潜像担持体は電子写真法によって静電潜像が形成され
る感光ドラムであり、矢印aの方向に回転可能である。In this figure, reference numeral 1 denotes an electrostatic latent image carrier that carries an electrostatic latent image to be imaged, and specifically, it is an endlessly movable photosensitive drum, a belt, a dielectric drum, a belt, or the like. The method of forming an electrostatic latent image thereon is not the gist of the present invention, and any known method may be used. In this embodiment, the electrostatic latent image carrier is a photosensitive drum on which an electrostatic latent image is formed by electrophotography, and is rotatable in the direction of arrow a.
本実施例の装置は現像剤容器21、現像剤保持部材であ
る現像スリーブ22(以下単にスリーブと呼ぶ)、磁界
発生手段である磁石23、スリーブ22上で現像部に搬
送される現像剤の量を制御する規制ブレード24(以下
単にブレードと呼ぶ)、交互電界形成手段である電源3
4などを有する。以下それぞれの構成を説明する。The apparatus of this embodiment includes a developer container 21, a developing sleeve 22 (hereinafter simply referred to as a sleeve) that is a developer holding member, a magnet 23 that is a magnetic field generating means, and an amount of developer that is conveyed to the developing section on the sleeve 22. A regulation blade 24 (hereinafter simply referred to as a blade) that controls the
4 etc. Each configuration will be explained below.
容器21は磁性粒子27とトナー粒子28とを混合物と
して有する現像剤を収容する。トナー粒子は本実施例で
は、例えばカーボン10部、ポリスチレン90部を主体
として形成された粒径7〜20μmの非磁性トナー粒子
である。トナー粒子と磁性粒子とは本実施例では、スリ
ーブ22近傍で磁性粒子の濃度が高く、スリーブ22か
ら離れたところでは低いように収容されているが、均等
な混合物として容器21内に収容してもよい。容器21
は第1図左下部に開口を有する。Container 21 contains a developer having a mixture of magnetic particles 27 and toner particles 28 . In this embodiment, the toner particles are non-magnetic toner particles having a particle size of 7 to 20 μm and are mainly formed of, for example, 10 parts of carbon and 90 parts of polystyrene. In this embodiment, the toner particles and magnetic particles are stored in the container 21 as a uniform mixture, with the concentration of the magnetic particles being high near the sleeve 22 and low in areas away from the sleeve 22. Good too. Container 21
has an opening at the lower left in FIG.
スリーブ22は、例えばアルミニウムなどの非磁性材料
製であり、容器21の上記開口部に設けられ、その表面
の一部を露出させ、他の面を容器21内に突入させてい
る。スリーブ22は図面に直角な軸の回りに回転可能に
軸支され、矢印すで示す方向に回転駆動される。本実施
例ではスリーブ22は円筒状のスリーブであるが、これ
は無端ベルトでもよい。The sleeve 22 is made of a non-magnetic material such as aluminum, and is provided at the opening of the container 21, with a part of its surface exposed and the other surface protruding into the container 21. The sleeve 22 is rotatably supported about an axis perpendicular to the drawing and is rotationally driven in the direction indicated by the arrow. Although the sleeve 22 is a cylindrical sleeve in this embodiment, it may be an endless belt.
スリーブ22は感光ドラム1に対して微小間隙をもって
対向して現像部を構成する。この現像部にはトナーおよ
び磁性粒子がスリーブ22によって搬送されている。The sleeve 22 opposes the photosensitive drum 1 with a small gap therebetween and constitutes a developing section. Toner and magnetic particles are conveyed to this developing section by a sleeve 22.
6T1石23はスリーブ22内部に静止的に固定され、
スリーブ22の回転時も不動である。磁石23は後述の
ブレード24と共同してスリーブ22上への現像剤塗布
量を制御するN 1iil極23a、現像磁極であるS
磁極23b、現像部通過後の現像剤を容器21内に搬送
するN磁極23cおよびS磁極23dを有する。S極と
N極は逆でもよい。この磁石は本実施例では永久磁石で
あるが、これに代えて電磁石を使用してもよい。The 6T1 stone 23 is fixed statically inside the sleeve 22,
It remains stationary even when the sleeve 22 rotates. The magnet 23 has an N pole 23a that controls the amount of developer applied onto the sleeve 22 in cooperation with a blade 24 to be described later, and an S pole 23a that is a developing magnetic pole.
It has a magnetic pole 23b, an N magnetic pole 23c and an S magnetic pole 23d that transport the developer into the container 21 after passing through the developing section. The south pole and north pole may be reversed. Although this magnet is a permanent magnet in this embodiment, an electromagnet may be used instead.
ブレード24は本実施例では、少なくともその先端が例
えばアルミニウムなどの非磁性材料製であり、容器21
の開口の上部近傍でスリーブ22の長手方向に延在し、
その基部は容器21に固定され、先端側はスリーブ22
の表面に間隙をもって対向している。ブレード24の先
端とスリーブ22の表面との間隙は50〜500Atm
、好ましくは100〜350μmであり、本実施例では
300μmである。この間隙が50μmより小さいと、
磁性粒子がこの間隙部に詰まり易く、500μmを越え
ると、磁性粒子およびトナーが多量に間隙を通過し、ス
リーブ22上に適当な厚さの現像剤層が形成できない。In this embodiment, the blade 24 has at least its tip made of a non-magnetic material such as aluminum, and the blade 24 is made of a non-magnetic material such as aluminum.
extending in the longitudinal direction of the sleeve 22 near the top of the opening;
Its base is fixed to a container 21, and its distal end is fixed to a sleeve 22.
facing the surface with a gap. The gap between the tip of the blade 24 and the surface of the sleeve 22 is 50 to 500 Atm.
, preferably 100 to 350 μm, and in this example, 300 μm. If this gap is smaller than 50 μm,
Magnetic particles tend to clog this gap, and if the diameter exceeds 500 μm, a large amount of magnetic particles and toner will pass through the gap, making it impossible to form a developer layer with an appropriate thickness on the sleeve 22.
現像剤層の淳さは後述の現像部における感光ドラム1と
スリーブ22との間隙よりも小さい(ただしこのとき現
像剤の厚さとは磁力が働いていない状態でのスリーブ2
2上での厚さである)。このような厚さの現像剤層を作
るためには、ブレード先端とスリーブ面との間隙は、ス
リーブ面と感光ドラム面の間隙と同等または小さいこと
が好ましいが、それ以上にしても可能である。The thickness of the developer layer is smaller than the gap between the photosensitive drum 1 and the sleeve 22 in the developing section, which will be described later.
2). In order to create a developer layer with such a thickness, it is preferable that the gap between the blade tip and the sleeve surface be equal to or smaller than the gap between the sleeve surface and the photosensitive drum surface, but it is also possible to make it larger. .
ブレード24の容器21内部側には、磁性粒子循環限定
部材26が設けられ、これは後述の磁性粒子の容器21
内での循環域を制限する。A magnetic particle circulation limiting member 26 is provided inside the container 21 of the blade 24, and this member 26 is connected to the magnetic particle container 21, which will be described later.
Limit the circulation area within.
電源34は感光ドラム1とスリーブ22との間に電圧を
印加して、それらの間の空隙に交互電界を形成させ、ス
リーブ22上の現像、剤からトナーを感光ドラム1に転
移させる。電源34による電圧は正側と負側のピーク電
圧が同じである対称型交互電圧でも、このような交互電
圧に直流電圧を重畳した形の非対称交互電圧でもよい。The power supply 34 applies a voltage between the photosensitive drum 1 and the sleeve 22 to form an alternating electric field in the gap therebetween, thereby transferring toner from the developer and agent on the sleeve 22 to the photosensitive drum 1. The voltage from the power supply 34 may be a symmetrical alternating voltage in which the peak voltages on the positive side and the negative side are the same, or an asymmetrical alternating voltage in which a DC voltage is superimposed on such an alternating voltage.
具体的な電圧値としては、例えば暗部電位−a o o
v、明部電位−200vの静電潜像に対して、−例と
して、直流電圧−300vを重畳してピーク・ピーク電
圧を500〜2200VPP、周波数200〜3000
Hz交互電圧をスリーブ22側に印加し、感光ドラム1
を接地電位に保持する。As a specific voltage value, for example, dark potential -a o o
For example, a direct current voltage of -300v is superimposed on an electrostatic latent image with a bright area potential of -200v, so that the peak-to-peak voltage is 500 to 2200VPP, and the frequency is 200 to 3000V.
A Hz alternating voltage is applied to the sleeve 22 side, and the photosensitive drum 1
is held at ground potential.
つぎに本実施例の現像装置の作動について説明する。ま
ず、容器21に磁性粒子27を投入する。投入された磁
性粒子はl1i1極23aおよび23dによってスリー
ブ22上に保持され、容器21内に面するスリーブ22
の表面全体に渡って付着し、磁性粒子層を構成する。こ
の磁性粒子層の磁極23aおよびIQ8i23 dに近
い部分では磁性粒子27は磁気ブラシを構成する。その
後、トナー28を容器21内に投入し、前記磁性粒子層
の外側にトナ一層を形成する。前記の最初に投入する磁
性粒子27は磁性粒子に対して、もともと2〜70%(
重量)トナーを含むことが好ましいが、磁性粒子のみと
してもよい。磁性粒子27は−Hスリーブ22表面上に
磁性粒子層として吸着保持されれば、装置の振動やかな
り大きな傾きによっても実質的な流動あるいは傾斜は発
生せず、スリーブ22の表面を覆った状態が維持される
。Next, the operation of the developing device of this embodiment will be explained. First, magnetic particles 27 are put into the container 21 . The charged magnetic particles are held on the sleeve 22 by the l1i1 poles 23a and 23d, and the sleeve 22 facing inside the container 21
The magnetic particles adhere to the entire surface of the magnetic particles and form a layer of magnetic particles. In the portion of this magnetic particle layer near the magnetic pole 23a and IQ8i23d, the magnetic particles 27 constitute a magnetic brush. Thereafter, toner 28 is put into the container 21 to form a single layer of toner on the outside of the magnetic particle layer. The magnetic particles 27 initially introduced have a ratio of 2 to 70% (based on the magnetic particles).
Weight) It is preferable that the toner is included, but it is also possible to include only magnetic particles. If the magnetic particles 27 are adsorbed and held as a magnetic particle layer on the surface of the -H sleeve 22, no substantial flow or inclination will occur even if the device is vibrated or tilted considerably, and the state in which the magnetic particles 27 cover the surface of the sleeve 22 will not occur. maintained.
つぎに、スリーブ22を矢印方向に回転すると、磁性粒
子は容器21の下部からスリーブ22の表面に沿った方
向に上昇し、ブレード24の近傍に至る。そこで、磁性
粒子の一部はトナーとともにブレード24の先端とスリ
ーブ22の表面との間隙を通過し、他部は部材26に衝
突した後、反転して磁性粒子の上昇経路の外側を重力に
よって下降して容器21の下部に至り、再びスリーブ2
2の近傍を上昇して上記動作を繰返す。なお、容器21
の下部からブレード24に向って上昇する磁性粒子27
のなかにはブレード24の近傍に至る前に反転して落下
するものもある。これは特にスリーブ22の表面から遠
い磁性粒子に顕著に見られる。Next, when the sleeve 22 is rotated in the direction of the arrow, the magnetic particles rise from the bottom of the container 21 in a direction along the surface of the sleeve 22 and reach the vicinity of the blade 24. Therefore, a part of the magnetic particles passes through the gap between the tip of the blade 24 and the surface of the sleeve 22 together with the toner, and the other part collides with the member 26, then reverses and descends by gravity on the outside of the ascending path of the magnetic particles. and reaches the bottom of the container 21, and then the sleeve 2
2 and repeat the above operation. In addition, the container 21
magnetic particles 27 rising toward the blade 24 from the bottom of the
Some of them turn around and fall before reaching the vicinity of the blade 24. This is particularly noticeable in magnetic particles far from the surface of the sleeve 22.
このようにして、ブレード24の近傍あるいはその手前
で反転して落下する磁性粒子はその外側のトナ一層から
トナー粒子を取込んで行く。In this way, the magnetic particles that turn around and fall near or in front of the blade 24 take in toner particles from the outer toner layer.
スリーブ22の回転とともにこのように循環することに
よって、トナー28は磁性粒子27およびスリーブ22
表面との摩擦によフて帯電する。By circulating in this manner with the rotation of the sleeve 22, the toner 28 is mixed with the magnetic particles 27 and the sleeve 22.
It becomes electrically charged due to friction with the surface.
ブレード24の手前近傍では、スリーブ22の表面に近
い磁性粒子27は磁極23aによってスリーブ22表面
に引付けられ、スリーブ22の回転とともにブレード2
4の下方を抜けて容器21外に出る。このさい磁性粒子
27はその表面に付着したトナーを一緒に運び出す。ま
た帯電したトナー粒子28の一部はスリーブ22表面に
鏡映力によって付着したままスリーブ22上を容器外に
出る。ブレード24はスリーブ22上に塗布される現像
剤量を規制する。Near the front of the blade 24, the magnetic particles 27 near the surface of the sleeve 22 are attracted to the surface of the sleeve 22 by the magnetic pole 23a, and as the sleeve 22 rotates, the blade 2
4 and exits the container 21. At this time, the magnetic particles 27 carry away the toner attached to their surfaces. Further, some of the charged toner particles 28 leave the container on the sleeve 22 while remaining attached to the surface of the sleeve 22 due to the reflection force. Blade 24 regulates the amount of developer applied onto sleeve 22.
このようにしてスリーブ22の表面上に形成された現像
剤層(磁性粒子27とトナー28との混合体)はスリー
ブ22の回転とともに感光ドラム1と対面する現像部に
至る。ここでは、感光ドラム1とスリーブ22との間に
印加される交互電界によってトナーがスリーブ22の表
面および6n性粒子の表面から潜像上に転移し、該潜像
を現像する。The developer layer (mixture of magnetic particles 27 and toner 28) thus formed on the surface of the sleeve 22 reaches a developing section facing the photosensitive drum 1 as the sleeve 22 rotates. Here, toner is transferred from the surface of the sleeve 22 and the surface of the 6n particles onto the latent image by an alternating electric field applied between the photosensitive drum 1 and the sleeve 22, and the latent image is developed.
ついで第2図をもって現像部におけるトナー並びに磁性
粒子の挙動について説明する。本実施例においては静電
潜像は負電荷(画像暗部)によって構成されているので
、静電潜像による電界は矢印aで示す方向である。トナ
ー粒子と磁性粒子は現像製蓋内での相互摩擦によりトナ
ーは正電荷、磁性粒子は負電荷を帯びている。磁性粒子
はその材質・形状その他によって決定される電荷の充放
電時定数によって電荷が注入され電界次第でその帯電極
性は変化しうる。Next, the behavior of toner and magnetic particles in the developing section will be explained with reference to FIG. In this embodiment, since the electrostatic latent image is composed of negative charges (dark parts of the image), the electric field due to the electrostatic latent image is in the direction indicated by arrow a. Due to mutual friction between the toner particles and the magnetic particles within the developer lid, the toner particles are positively charged and the magnetic particles are negatively charged. Charge is injected into the magnetic particles according to the charge/discharge time constant determined by the material, shape, etc. of the particles, and the polarity of the charge can change depending on the electric field.
静電潜像が口n部例えば−600Vであり、スリーブ2
2側に交互電界の正成分が印加されている位相では、こ
れによる電界の方向は潜像による電界の方向と一致して
いる。この時電界によって磁性粒子のfi!!51に注
入される電荷の量は最大となり、磁性粒子は正電荷を帯
び、穂51は図示(第2図a)の如く最大起立状態とな
って、長い穂は感光ドラム1表面に伸び、短い穂は電界
の作用により感光ドラム1表面へ飛翔する。The electrostatic latent image is -600V at the mouth part, for example, and the sleeve 2
In the phase in which the positive component of the alternating electric field is applied to the second side, the direction of the electric field due to this matches the direction of the electric field due to the latent image. At this time, the electric field causes the magnetic particles to fi! ! The amount of charge injected into the photosensitive drum 1 reaches its maximum, the magnetic particles become positively charged, and the ears 51 reach their maximum standing state as shown in the figure (Fig. 2 a), with the long ears extending over the surface of the photosensitive drum 1 and the short ears The ears fly to the surface of the photosensitive drum 1 due to the action of the electric field.
一方トナーは絶縁性のため電荷の注入効果は少なく常に
正極性に帯電しているので、スリーブ22および磁性粒
子の表面上のトナーはこの空間に形成されている電界に
よって感光ドラム1に転移する。このときに穂51は粗
の状態で起立しているので、スリーブ22表面は露出し
ており、トナー28はスリーブ22表面および穂51の
表面の両方から離脱する。加えて、穂51にはトナー2
8と同極性の電荷が存在するため、穂51表面上のトナ
ー28は電気的反発力によってさらに移動し易い。On the other hand, since the toner is insulating, the charge injection effect is small and it is always positively charged, so the toner on the sleeve 22 and the surface of the magnetic particles is transferred to the photosensitive drum 1 by the electric field formed in this space. At this time, since the ears 51 stand up in a rough state, the surface of the sleeve 22 is exposed, and the toner 28 separates from both the sleeve 22 surface and the surface of the ears 51. In addition, toner 2 is applied to the ears 51.
Since there is a charge having the same polarity as that of toner 8, the toner 28 on the surface of the ears 51 is more likely to move due to electrical repulsion.
交互電圧成分の負の成分がスリーブ22に印加される位
相では、交互電圧による電界(矢印b)は静電潜像によ
る電界(矢印a)と逆方向である。したがってこの空間
部での電界は逆方向に強くなり、正極性の電荷を帯びた
磁性粒子はスリーブ22側へ引かれ、長い穂は縮み、短
い穂はスリーブ22表面へ飛翔する。In the phase in which the negative component of the alternating voltage component is applied to the sleeve 22, the electric field due to the alternating voltage (arrow b) is in the opposite direction to the electric field due to the electrostatic latent image (arrow a). Therefore, the electric field in this space becomes stronger in the opposite direction, and the positively charged magnetic particles are drawn toward the sleeve 22, the long ears shrink, and the short ears fly toward the sleeve 22 surface.
一方、感光ドラム1上のトナー28は前述のごとく正極
性に帯電しているので、この空間に形成されている電界
によってスリーブ22あるいは磁性粒子27に逆転移す
る。このようにしてトナー28は感光ドラム1とスリー
ブ22表面あるいは磁性粒子27表面との間を往復運動
し、感光ドラム1およびスリーブ22の回転によって、
これらの間の空間が広がるにつれて、電界が弱くなると
ともに現像作用が完了する。On the other hand, since the toner 28 on the photosensitive drum 1 is positively charged as described above, it is reversely transferred to the sleeve 22 or the magnetic particles 27 by the electric field formed in this space. In this way, the toner 28 moves back and forth between the photosensitive drum 1 and the surface of the sleeve 22 or the surface of the magnetic particles 27, and as the photosensitive drum 1 and sleeve 22 rotate,
As the space between them increases, the electric field weakens and the development action is completed.
又逆に静電潜像が明部例えば−100Vである時、スリ
ーブ22側に交互電界の正成分が印加されている位相に
おいても、電界により磁性粒子の穂に注入される電荷は
殆どなく、磁性粒子は後述するようにスリーブに負成分
が印加された位相時に注入されて負極性に帯電されたま
まであり、電界により長い穂は縮み、短い穂はスリーブ
22表面へ飛翔する。Conversely, when the electrostatic latent image is bright, for example at -100V, there is almost no charge injected into the ears of the magnetic particles by the electric field even in the phase where the positive component of the alternating electric field is applied to the sleeve 22 side. As will be described later, the magnetic particles are injected and remain negatively charged during the phase in which a negative component is applied to the sleeve, and the long ears shrink due to the electric field, and the short ears fly toward the surface of the sleeve 22.
トナーはこの空間に形成されている電界によって感光ド
ラム1に転移するが、このときに穂51は縮んでおり、
スリーブ22表面が覆われており、スリーブ22からの
トナーの離脱を抑制し、加えて穂51にはトナーと逆極
性の電荷が存在するために、穂51表面上のトナー28
は電気的吸引力によりトナーの離脱を抑制する。The toner is transferred to the photosensitive drum 1 by the electric field formed in this space, but at this time, the ears 51 are shrunk.
The surface of the sleeve 22 is covered to suppress the separation of the toner from the sleeve 22, and in addition, since the ears 51 have charges of opposite polarity to the toner, the toner 28 on the surface of the ears 51 is covered.
suppresses toner separation by electric attraction force.
交互電圧成分の負の成分がスリーブ22に印加される位
相では、逆方向矢印す方向の電界が最大となり、磁性粒
子の穂に注入される電荷量も増し磁性粒子はより負極性
の電荷を帯び穂51は最大起立状態となり、長い穂は感
光ドラム表面に伸び、短い穂は電界の作用により感光ド
ラム表面へ飛翔する。In the phase in which the negative component of the alternating voltage component is applied to the sleeve 22, the electric field in the direction indicated by the opposite arrow is at its maximum, and the amount of charge injected into the ears of the magnetic particles also increases, causing the magnetic particles to become more negatively charged. The ears 51 are in the maximum standing state, and the long ears extend to the surface of the photosensitive drum, and the short ears fly to the surface of the photosensitive drum due to the action of the electric field.
一方、感光ドラム上のトナーはこの空間に形成されてい
る電界によってスリーブ22又は磁性粒子へ転移する。On the other hand, the toner on the photosensitive drum is transferred to the sleeve 22 or the magnetic particles by the electric field formed in this space.
このときに穂51は粗の状態で起立しているのでスリー
ブ22表面は露出しており、トナーが戻りやすくなって
いるとともに、トナーと逆極性に帯電した磁性粒子が近
接しているために電気的吸引力によりトナーはさらに感
光体表面より離脱しやすい。At this time, since the ears 51 are standing up in a rough state, the surface of the sleeve 22 is exposed, making it easier for the toner to return. The toner is further easily separated from the surface of the photoreceptor due to the attraction force.
穂51にはトナー28との摩擦帯電電荷もしくは鏡映電
荷、感光ドラムl上の静電潜像電荷および感光ドラム1
とスリーブ22との間の交互電界によって注入される電
荷が存在するが、その状態は磁性粒子27の材質その他
によって決定される電荷の充放電時定数によって変化す
る。The ears 51 have triboelectric charges or mirror charges with the toner 28, electrostatic latent image charges on the photosensitive drum 1, and photosensitive drum 1.
There is a charge injected by the alternating electric field between the magnetic particles 27 and the sleeve 22, but its state changes depending on the charging/discharging time constant of the charge determined by the material of the magnetic particles 27 and other factors.
一般的に磁性粒子の抵抗値が低い程電荷注入が多く画像
暗部、明部に磁性粒子が電荷の注入により現像されてし
まう。又逆に抵抗が極めて高い場合には常にトナーとは
逆極性の電荷を保持するため、背景部への磁性粒子カブ
リとなりやすく、磁性粒子の抵抗材質形状等を適切に選
択することにより磁性粒子の付着を防止することができ
る。Generally, the lower the resistance value of the magnetic particles, the more charges are injected, and the magnetic particles are developed in dark and bright areas of the image due to charge injection. On the other hand, when the resistance is extremely high, the toner always retains a charge of the opposite polarity, which tends to cause the magnetic particles to fog on the background area. Adhesion can be prevented.
上記説明の磁性粒子の挙動を確実にならしめるには、現
像スリーブと感光体間に印加されるバイアス電界の電位
(交流成分と直流成分を重畳したもの)がトナーを感光
体から現像スリーブ方向への波形成分のピーク値■2と
該感光体のgB部電位V、の値がIVp I>Ivo
lとな’l、交互電圧による電界が静電潜像による電
界を上まわることが好ましい。In order to ensure the behavior of the magnetic particles described above, the potential of the bias electric field (a combination of alternating current and direct current components) applied between the developing sleeve and the photoreceptor moves the toner from the photoreceptor toward the developing sleeve. The value of the peak value of the waveform component 2 and the gB part potential V of the photoreceptor is IVp I>Ivo
Preferably, the electric field due to the alternating voltage exceeds the electric field due to the electrostatic latent image.
以上の如く、磁性粒子の穂は上述の交互電界によって微
小なしかし激しい振動飛翔状態となる。As described above, the ears of magnetic particles are brought into a flying state of slight but intense vibration due to the above-mentioned alternating electric field.
このように現像部に交番電界を加え、トナー並びに磁性
粒子を振動飛翔させることによって次の如く効果が発生
する。By applying an alternating electric field to the developing section in this manner and causing the toner and magnetic particles to vibrate and fly, the following effects are produced.
トナーを磁気ブラシ及びスリーブ表面から飛翔させ現像
するために現像効率が極めて高くなる。The development efficiency is extremely high because the toner is ejected from the surface of the magnetic brush and sleeve.
従って現像剤の塗布量も比較的小量ですみ、現像像の解
像力が高まる。また現像効率が高いため現像スリーブと
感光体の相対速度をほぼ同一とすることが可能であり、
相対速度をつけることで生じるベタ現像部の掃き寄せ等
は生じない。さらに相対速度をつけても掃き寄せを軽減
する効果もある。Therefore, the amount of developer applied is relatively small, and the resolution of the developed image is increased. In addition, because the developing efficiency is high, it is possible to make the relative speed between the developing sleeve and the photoreceptor almost the same.
Sweeping of the solid development area, which occurs when the relative speed is increased, does not occur. Furthermore, adding relative speed also has the effect of reducing sweeping.
又、磁性粒子が交番電界によって振動しているため、1
木1木の磁気ブラシの跡も発生せず、極めて高画質な現
像画像を得ることができる。Also, since the magnetic particles are vibrated by an alternating electric field, 1
There are no traces of the magnetic brush, and extremely high-quality developed images can be obtained.
さらに磁性粒子がスリーブと感光体のなす空間を6動す
るだけの交番電界を印加することにより、前述の様な磁
性粒子の飛翔の際に暗部セはトナーと共に挙動して現像
を促進し、明部ではトナーと反対の挙動を示し、感光体
表面に付着しているトナーを引き離す効果がありカブリ
防止になる。Furthermore, by applying an alternating electric field sufficient to cause the magnetic particles to move through the space formed by the sleeve and the photoreceptor, the dark area behaves together with the toner when the magnetic particles fly as described above, promoting development and brightening. It behaves in the opposite way to that of toner, and has the effect of separating toner adhering to the surface of the photoreceptor, thereby preventing fogging.
さらに感光体表面に付着した磁性粒子も最終的には、磁
気力及びこの電界による移動力によって現像スリーブ側
に引き戻され、磁性粒子の感光体への付着量を減少する
ことができる。Furthermore, the magnetic particles adhering to the surface of the photoreceptor are eventually pulled back toward the developing sleeve by the magnetic force and the moving force caused by the electric field, thereby reducing the amount of magnetic particles adhering to the photoreceptor.
さらに磁性粒子の穂が偏在している場合においても、磁
性粒子の飛翔の際に穂が一部崩れ磁性粒子のならし効果
もある。Furthermore, even when the ears of magnetic particles are unevenly distributed, when the magnetic particles fly, some of the ears collapse and have the effect of smoothing out the magnetic particles.
比較的低い抵抗値の磁性粒子27を使用する場合、感光
ドラム1とスリーブ22との間に印加する交互電圧は、
そのピーク値の際に潜像の暗部、明部のいずれにおいて
も間隙放電が発生しないように設定する必要がある。一
方、比較的高い抵抗値の穂51を使用する場合は、交互
電圧の周波数と穂51の充放電時定数を適切に選択する
ことによって、間隙電圧が放電開始電圧に到達しないよ
うにすることが好ましい。When using magnetic particles 27 with a relatively low resistance value, the alternating voltage applied between the photosensitive drum 1 and the sleeve 22 is as follows:
Settings must be made so that no gap discharge occurs in either the dark or bright areas of the latent image when the peak value is reached. On the other hand, when using ears 51 with a relatively high resistance value, it is possible to prevent the gap voltage from reaching the discharge starting voltage by appropriately selecting the frequency of the alternating voltage and the charging/discharging time constant of the ears 51. preferable.
これらを考慮した場合、穂51全体の抵抗としては、感
光ドラム1に現像ブラシが接触した状態で穂51の高さ
方向の抵抗が10″〜106Ωcmの程度が好ましく、
現像電極効果を期待する場合は10′。〜106Ωcf
fI程度が好ましい。Taking these into consideration, the resistance of the entire spike 51 in the height direction of the spike 51 with the developing brush in contact with the photosensitive drum 1 is preferably in the range of 10'' to 106 Ωcm;
If you expect a developing electrode effect, set it to 10'. ~106Ωcf
Approximately fI is preferable.
磁性粒子27は平均粒径が30〜iooμ、好ましくは
40〜80μである。一般的に平均粒径の小さいもの程
、スリーブ22上でのトナーの摩擦帯電特性が優れ、ス
リーブゴースト(ベタ黒原稿を現像した直後のスリーブ
回転による現像で濃度が低くなる現象あるいはスリーブ
の回転ごとに現像濃度が低下する現象として現れる)が
発生しなくなる。しかし粒径が小さい場合は、静電保持
体への磁性粒子の付着を発生する傾向がある。この付着
位置は磁性粒子の抵抗値によって異なり、例えば比較的
低抵抗なものでは画像部に付着し、高抵抗なものでは非
画像部に付着する。これは一般的傾向で、実際には磁性
粒子の磁気的特性、表面形状、表面処理材(樹脂コート
を含む)も多少隈三響する。The magnetic particles 27 have an average particle size of 30 to iooμ, preferably 40 to 80μ. In general, the smaller the average particle size, the better the triboelectric charging characteristics of the toner on the sleeve 22, and the sleeve ghost (a phenomenon in which the density decreases due to the rotation of the sleeve immediately after developing a solid black original, or every rotation of the sleeve). (which appears as a phenomenon in which the developing density decreases) will no longer occur. However, if the particle size is small, there is a tendency for the magnetic particles to adhere to the electrostatic holder. The position of this adhesion differs depending on the resistance value of the magnetic particles; for example, those with relatively low resistance will adhere to the image area, and those with high resistance will adhere to the non-image area. This is a general tendency, and in reality, the magnetic properties of magnetic particles, surface shape, and surface treatment materials (including resin coating) also have some influence.
つぎに、第1図の現像装置を用いた具体例について述べ
る。第1図において、スリーブ22として直径20mm
のアルミスリーブの表面を、アランダム砥粒により不定
型サンドブラスト処理したものを用い、磁石23として
4極着磁でN極、S極が交互に第1図で示されるような
ものを用いた。Next, a specific example using the developing device shown in FIG. 1 will be described. In FIG. 1, the sleeve 22 has a diameter of 20 mm.
The surface of the aluminum sleeve was subjected to amorphous sandblasting treatment using alundum abrasive grains, and the magnet 23 was magnetized with four poles, with N and S poles alternating as shown in FIG.
磁石23による表面磁束密度の最大値は約900ガウス
であった。The maximum value of the surface magnetic flux density due to the magnet 23 was about 900 Gauss.
ブレード24としては1.2mm厚の非磁性ステンレス
を用い、上記角度θは15°とした。The blade 24 was made of nonmagnetic stainless steel with a thickness of 1.2 mm, and the angle θ was 15°.
磁性粒子としては、表面にシリコン樹脂コートした平均
粒径55μmのフェライト(最大1ifi化60 e
m u / g )を用いた。As magnetic particles, ferrite with an average particle diameter of 55 μm (maximum 1ifi 60 e
mu/g) was used.
非磁性トナーとしては、スチレン/ブタジェン共重合体
系樹脂100部に銅フタロシアニン系顔料5部から成る
平均粒径10μのトナー粉体にコロイダルシリカ0.6
%を外添したブルートナーを用いたところ、スリーブ2
2表面上にコーティング厚約20〜30μmのトナー塗
布層を得、さらにその上層として100〜200μの磁
性粒子層を得た。各磁性粒子の表面上には上記トナーが
付着している。The non-magnetic toner is a toner powder with an average particle size of 10μ consisting of 100 parts of styrene/butadiene copolymer resin and 5 parts of copper phthalocyanine pigment, and 0.6 parts of colloidal silica.
When using blue toner with external addition of %, sleeve 2
A toner coating layer with a coating thickness of about 20 to 30 .mu.m was obtained on the surface of No. 2, and a magnetic particle layer with a thickness of 100 to 200 .mu.m was further formed as an upper layer thereon. The toner is attached to the surface of each magnetic particle.
このときのスリーブ22上の磁性粒子と全トナーとの合
計重量は約2.43xlO−2g/cm2であった。At this time, the total weight of the magnetic particles and all the toner on the sleeve 22 was about 2.43xlO-2g/cm2.
磁性粒子は現像部およびその近傍でスリーブ22内の磁
極23bにより磁界によって穂立ちして、最大要約0.
9mmの穂立ちブラシを形成していた。The magnetic particles are made to stand up by the magnetic field generated by the magnetic pole 23b in the sleeve 22 in the developing area and its vicinity, and the maximum density is 0.
It formed a 9mm standing brush.
帯電量をブローオフ法で測定したところスリーブ上及び
磁性粒子上のトナーのトリボ電荷量が+10μC/gで
あった。When the amount of charge was measured by a blow-off method, the amount of triboelectric charge of the toner on the sleeve and on the magnetic particles was +10 μC/g.
この現像装置をキャノン(株)製PC−10型複写機に
組み込み、感光ドラム3(有機感光材料製)とスリーブ
22の表面との間隔を350μmとした。静電潜像を暗
部電位を一620■、明部電位を一180Vとし、バイ
アス電源の直流電圧を一260vとし、交流成分を周波
数並びにピーク対ピーク電圧を変えて現像を行ったとこ
ろ、第3図のような相関図が得られた。This developing device was installed in a PC-10 copying machine manufactured by Canon Inc., and the distance between the photosensitive drum 3 (made of an organic photosensitive material) and the surface of the sleeve 22 was set to 350 μm. When the electrostatic latent image was developed with the dark potential at -620V, the light potential at -180V, the DC voltage of the bias power supply at -260V, and the frequency and peak-to-peak voltage of the AC component changed, the third A correlation diagram as shown in the figure was obtained.
周波数200Hz未満では磁性粒子の振動飛mが充分で
なく、磁気ブラシ跡が現像画像に表われ好ましくない。If the frequency is less than 200 Hz, the vibration flight of the magnetic particles will not be sufficient, and magnetic brush marks will appear on the developed image, which is undesirable.
又3000Hzを越えると、トナー、磁性粒子共に電界
に追随しなくなり、画像が薄くカブリやすい画像となり
好ましくない。縦線で影を付した領域はスリーブ・感光
体間で放電をしやすくなる領域であり、高地等気圧の低
い地域ではこの値はさらに低いものとなる。横線で影を
付した領域は背景部に地力ブリを生じやすい領域であり
、斜線で影を付した領域は、磁性粒子が充分に空隙を飛
翔しなくなる領域である。従ってこれらのラインで囲ま
れた領域で現像を行うことが好ましい。さらに画像濃度
階調性(カブリ、ラチチュード等より、より好ましくは
周波数は1〜2KHz、VPpは800〜1500Vの
領域が好ましい。If the frequency exceeds 3000 Hz, neither the toner nor the magnetic particles can follow the electric field, resulting in an image that is thin and prone to fogging, which is undesirable. The area shaded by vertical lines is the area where discharge is likely to occur between the sleeve and the photoconductor, and this value is even lower in areas with low isobaric pressure at high altitudes. The area shaded with horizontal lines is an area where ground force blur is likely to occur in the background, and the area shaded with diagonal lines is an area where magnetic particles do not fly sufficiently through the gap. Therefore, it is preferable to perform development in the area surrounded by these lines. Further, in view of image density gradation (fogging, latitude, etc.), the frequency is preferably 1 to 2 KHz, and the VPp is preferably in the range of 800 to 1500V.
さらに好ましくは1.4〜1.8KHz、1000〜1
350Vppの領域が良い。同様にしてS−D間隔を2
50〜500μmに変えて同じ設定で現像を行った時、
最も良好な画像を得られたのは表1に記載された交番電
界を印加したときであった。More preferably 1.4 to 1.8 KHz, 1000 to 1
A region of 350 Vpp is good. Similarly, set the S-D interval to 2.
When I changed it to 50-500μm and developed it with the same settings,
The best image was obtained when the alternating electric field listed in Table 1 was applied.
同様な実験より実用上では周波数1〜2,2KHz、V
pp800〜2200、S −D gap250〜70
0μmの範囲において、はぼ良好な画像が得られた。S
−D gapを800μm以上にすると、交番電界電
圧を高くしても細線の再現が悪くなり好ましくない。Based on similar experiments, in practical use the frequency is 1 to 2.2 KHz, V
pp800-2200, S-D gap250-70
Very good images were obtained in the 0 μm range. S
-D gap of 800 μm or more is not preferable because the reproduction of fine lines deteriorates even if the alternating field voltage is increased.
表I S−D間隔と最適交番電界
磁性粒子の粒径をさらに細かく例えば平均粒径40μm
位になると適切な交番電界の範囲は変化し、周波数はほ
ぼ同等であるが、印加電圧は500〜1600Vが良好
となる。これは磁性粒子の粒径が細かくなることによっ
て表面積が増し、磁性粒子の電荷量が増し、磁気容量が
減フたことによりスリーブ内の固定磁極による拘束力が
低下し、電界の力をより顕著に受けるために生じると考
えられる。但し、小粒径の磁性粒子は感光体に付着しや
すく、30μm以下の粒径のものでは、商業的な600
〜900ガウスの現像磁極をもった現像装置においては
、交番電圧を印加しても感光体上の磁性粒子を回収しき
れない。Table I S-D spacing and optimum alternating field The particle size of the magnetic particles can be further refined to, for example, an average particle size of 40 μm.
The appropriate range of the alternating electric field changes when the voltage reaches 500V, and although the frequency is almost the same, the applied voltage is preferably 500 to 1600V. This is because as the particle size of the magnetic particles becomes finer, the surface area increases, the amount of charge on the magnetic particles increases, and the magnetic capacity decreases, which reduces the restraining force of the fixed magnetic pole inside the sleeve, making the force of the electric field more pronounced. It is thought that this occurs due to the exposure to However, small-sized magnetic particles tend to adhere to the photoreceptor, and those with a particle size of 30 μm or less
In a developing device having a developing magnetic pole of ~900 Gauss, the magnetic particles on the photoreceptor cannot be completely recovered even if an alternating voltage is applied.
以上に説明のごとく、本実施例によれば、高画像濃度、
高現像効率で、かぶり、ゴースト像、掃目むら、負性特
性のない現像を行なうことができる。As explained above, according to this embodiment, high image density,
It is possible to perform development with high development efficiency without fogging, ghost images, uneven sweeping, or negative characteristics.
スリーブ22の材料としてはアルミニウムのほか真ちゅ
うやステンレス鋼などの導電体、紙筒や合成樹脂の円筒
を使用可能である。また、これら円筒の表面を導電処理
するか、導電体で構成すると現像電極として機能させる
こともできる。さらに、芯ロールを用いてその周面に導
電性の弾性体、例えば導電性スポンジを巻装して構成し
てもよい。As the material of the sleeve 22, in addition to aluminum, conductive materials such as brass and stainless steel, paper tubes, and synthetic resin cylinders can be used. Furthermore, if the surfaces of these cylinders are subjected to conductive treatment or made of a conductive material, they can function as developing electrodes. Furthermore, a core roll may be used and a conductive elastic body, for example, a conductive sponge, may be wound around the circumferential surface of the core roll.
現像部の磁極23bについては、実施例では現像部の中
央に磁極を配置したが、中央からずらした位置としても
よく、また磁極間に現像部を配置するようにしてもよい
。Regarding the magnetic pole 23b of the developing section, although the magnetic pole is arranged at the center of the developing section in the embodiment, it may be placed at a position shifted from the center, or the developing section may be arranged between the magnetic poles.
トナーには、流動性を高めるためにシリカ粒子や、例え
ば転写方式画像形成方法に於て潜像保持部材たる感光ド
ラム3の表面の研磨のために研磨剤粒子等を外添しても
よい。トナー中に少量の磁性粒子を加えたものを用いて
もよい。すなわち、磁性粒子に比べ著しく弱い磁性であ
り、トリボイ1F電可能であれば磁性トナーも用いるこ
とができる。Silica particles may be externally added to the toner to improve fluidity, and abrasive particles may be added to the toner to polish the surface of the photosensitive drum 3, which is a latent image holding member in a transfer image forming method, for example. A toner containing a small amount of magnetic particles may also be used. That is, it has significantly weaker magnetism than magnetic particles, and if possible, magnetic toner can also be used.
ゴースト像現象を防止するために、容器21内へ戻り回
動じたスリーブ22面から現像に供されずにスリーブ2
2上に残った現像剤層を、一旦スフレーバ手段(不図示
)でかき落し、そのかき落しされたスリーブ面を磁性粒
子層に接触させて現像剤の再コーテイングを行なわせる
ようにしてもよい。In order to prevent the ghost image phenomenon, the sleeve 2 is not subjected to development from the surface of the sleeve 22 that has returned to the container 21 and has been rotated.
The developer layer remaining on the magnetic particle layer 2 may be scraped off once by a soflavor means (not shown), and the scraped sleeve surface may be brought into contact with the magnetic particle layer to re-coat the developer.
磁性粒子とトナーとの濃度を検出して、この出力に応じ
て自動的にトナーを補給する機構を設けてもよい。A mechanism may be provided that detects the concentration of magnetic particles and toner and automatically replenishes toner according to this output.
本発明の現像装置は容器21、スリーブ22およびブレ
ード24などを一体化した使いすてタイプの現像器とし
ても、画像形成装置に固定された通常現像器としても使
用可能である。The developing device of the present invention can be used as a disposable type developing device that integrates a container 21, a sleeve 22, a blade 24, etc., or as a normal developing device fixed to an image forming apparatus.
(発明の効果)
以上説明のごとく、本発明によれば、高画像濃度で高現
像効率現像装置が提供される。(Effects of the Invention) As described above, according to the present invention, a developing device with high image density and high development efficiency is provided.
第1図は本発明の現像法を用いる実施例による現像装置
の断面図である。
第2図(a)、(b)は第1図の現像装置の現像部の拡
大断面図である。
第3図は本発明の実施例による現像装置の現像l・・・
潜像担持体(感光ドラム)
21・・現像剤容器(容器)
22・・現像剤保持部材(スリーブ)
23・・磁界発生手段(磁石)
27・・磁性粒子
28・・トナー粒子(トナー)
園浦館KfhFIG. 1 is a sectional view of a developing device according to an embodiment using the developing method of the present invention. 2(a) and 2(b) are enlarged sectional views of the developing section of the developing device shown in FIG. 1. FIG. FIG. 3 shows a developing device according to an embodiment of the present invention.
Latent image carrier (photosensitive drum) 21... Developer container (container) 22... Developer holding member (sleeve) 23... Magnetic field generating means (magnet) 27... Magnetic particles 28... Toner particles (toner) Uradate Kfh
Claims (3)
性粒子からなる磁気ブラシ層を持ち、該現像剤担持体と
該静電潜像担持体との間に交流成分と直流成分からなる
バイアス電界を印加して現像する現像方法において、前
記交流成分の電界を周波数200〜3000Hzとし、
ピークトウピーク電圧を静電潜像を破壊せず、かつ現像
領域において磁性粒子を前記現像剤担持体と前記静電潜
像間を移動させる電圧とすることを特徴とする現像方法
。(1) A toner particle layer and a magnetic brush layer consisting of toner particles and magnetic particles are provided on the developer carrier, and an alternating current component and a direct current component are provided between the developer carrier and the electrostatic latent image carrier. In a developing method in which development is performed by applying a bias electric field, the electric field of the alternating current component has a frequency of 200 to 3000 Hz,
A developing method characterized in that the peak-to-peak voltage is set to a voltage that does not destroy the electrostatic latent image and moves magnetic particles between the developer carrier and the electrostatic latent image in a developing region.
200V_P_Dであることを特徴とする特許請求の範
囲第1項記載の現像方法。(2) The voltage of the AC component of the bias electric field is set to 500 to 2
The developing method according to claim 1, characterized in that the voltage is 200V_P_D.
体上から現像剤保持部材へ移動させる方向の波形成分の
ピーク値V_Pと該潜像保持体上の暗部潜像電位V_D
の関係が |V_P|>|V_D| であることを特徴とする特許請求の範囲第1項又は第2
項記載の現像方法。(3) The voltage of the bias power supply is determined by the peak value V_P of the waveform component in the direction of moving the toner from the electrostatic latent image holding member to the developer holding member and the dark area latent image potential V_D on the latent image holding member.
Claim 1 or 2, characterized in that the relationship is |V_P|>|V_D|
Development method described in section.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3546086A JPS62192758A (en) | 1986-02-20 | 1986-02-20 | Developing method |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3546086A JPS62192758A (en) | 1986-02-20 | 1986-02-20 | Developing method |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS62192758A true JPS62192758A (en) | 1987-08-24 |
Family
ID=12442395
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP3546086A Pending JPS62192758A (en) | 1986-02-20 | 1986-02-20 | Developing method |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS62192758A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US10197948B2 (en) | 2014-09-17 | 2019-02-05 | Ricoh Company, Ltd. | Developing device and image forming apparatus |
-
1986
- 1986-02-20 JP JP3546086A patent/JPS62192758A/en active Pending
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US10197948B2 (en) | 2014-09-17 | 2019-02-05 | Ricoh Company, Ltd. | Developing device and image forming apparatus |
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