JPS58186765A - Developing method - Google Patents

Abstract

PURPOSE:To execute a stable development having a wide allowable range of bias voltage, which is capable of obtaining an inverted development of high quality, and also to execute a regular development, too, by supplying a magnetic toner onto a sleeve whose surface is conductive, and relatively moving a magnetic field generating means and the conductive sleeve. CONSTITUTION:When bias voltage and an adhering quantity of a toner 5 are derived in case when the surface is slide-rubbed by a toner brush by using zinc oxide paper as a recording body 1 and carrying it to a developing area 2 in a state that it remains uncharged, a result as shown in the figure is obtained. When the bias voltage increases and reaches some values V+t, V-t, the toner 5 adheres, and when the bias voltage is further raised, the toner adherent quantity increases suddenly. That is to say, when the bias voltage reaches V+1, V-1, the toner 5 adheres to a non-charged area, therefore, the bias voltage V+1 and V-1 in this case are called development start voltage. In this case, there is relation of ¦V+s¦>¦V+t¦, ¦V-t¦ against saturation potential V+s of the recording body 1, and ¦V+t¦approx.=¦V-t¦, therefore, the toner 5 is apt to be charged positive and negative. Accordingly, when an inverted development is executed by use of a toner having such a charging characteristic, adhering of the toner to the non-charged area becomes apt to be generated by a small electric field.

Description

【発明の詳細な説明】 本発明は静電潜像を保持してなる記録体の表面に一成分
系の磁性トナーを付着させてトナー像を得る現像方法に
関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a developing method for obtaining a toner image by depositing a one-component magnetic toner on the surface of a recording medium holding an electrostatic latent image.

電子写真を利用した乾式複写方式においては、通常、記
録体の光導電性記録層の表面を一様に帯電後光像で露光
して静電潜像を形成し、次いで現像剤を用いて静電潜像
を顕像化して現像画像を得ている。ここで光導電性記録
層としては、光導電性セレニウム、絶縁性バインダー中
に光導電性酸化亜鉛粒子を分散させた層、絶縁性バイン
ダー中に光導電性硫化カドミニウムを分散させた層の上
にポリエステルフィルムを形成したもの、ポリビニルカ
ルバソール、ポリ−Ｎ−ビニルカルバソール等の有機光
導電体層などが知られている。In the dry copying method using electrophotography, the surface of the photoconductive recording layer of the recording medium is usually uniformly charged and then exposed to light to form an electrostatic latent image, and then a developer is used to develop the electrostatic latent image. A developed image is obtained by visualizing the electrostatic latent image. Here, the photoconductive recording layer includes photoconductive selenium, a layer in which photoconductive zinc oxide particles are dispersed in an insulating binder, and a layer in which photoconductive cadmium sulfide is dispersed in an insulating binder. Organic photoconductor layers formed of polyester films, polyvinylcarbasol, poly-N-vinylcarbasol, and the like are known.

上記現像剤としては、例えば特開昭５０−２１７５５号
公報や特開昭５２−９４１４２号公報等に記載されてい
るように鉄粉、鋼球、フェライト等の強磁性キャリア（
粒径５０〜２００μｍ程度）とバインダー樹脂と顔料、
染料等の着色剤を主成分とするトナー粒子からなる二成
分現像剤が従来から使用されている。この二成分現像剤
は現像前に予め混合攪拌されてトナーとキャリアが摩擦
帯電により互いに逆極性の電荷を保持し、よってキャリ
ア粒子の表面にトナー粒子が静電的に保持される。The developer may be a ferromagnetic carrier such as iron powder, steel balls, ferrite, etc., as described in, for example, JP-A-50-21755 and JP-A-52-94142.
(particle size of about 50 to 200 μm), binder resin and pigment,
Two-component developers consisting of toner particles whose main component is a colorant such as a dye have been used. This two-component developer is mixed and stirred in advance before development, and the toner and carrier hold charges of opposite polarity to each other due to triboelectric charging, so that the toner particles are electrostatically held on the surface of the carrier particles.

この現像剤により磁気ブラシを形成し、この磁気ブラシ
で記録体の表面を摺擦することにより現像剤中のトナー
が静電潜像に付着して現像が行われる。This developer forms a magnetic brush, and by rubbing the surface of the recording medium with this magnetic brush, the toner in the developer adheres to the electrostatic latent image and development is performed.

二成分現像剤を用いる場合、通常の電子写真複写機にお
いてはトナーとキャリア粒子の帯電特性の選択によって
トナーを静’ｌ［像と逆極性に帯電させ、そしてトナー
を未篇光部分（以下帯電領域という）に付着させてポジ
画ｇＩヲ得ている。これに対シ、例えばコンピューター
の端末機器であるプリンターにおいては、トナーを静電
潜像と同極性に帯電させ、そしてトナーを無光部分（以
下非帯電領域という）に付着させてネガ画像（以下反転
画像という）を得ている。When using a two-component developer, in an ordinary electrophotographic copying machine, the toner is statically charged to the opposite polarity to the image by selecting the charging characteristics of the toner and carrier particles, and the toner is charged to the unprinted light area (hereinafter referred to as charged). A positive image is obtained by adhering it to a region (referred to as a region). In contrast, in printers, which are computer terminal devices, for example, toner is charged to the same polarity as the electrostatic latent image, and the toner is deposited on non-light areas (hereinafter referred to as uncharged areas) to create a negative image (hereinafter referred to as uncharged area). The result is a reversed image).

しかして二成分現像剤を使用する場合は、キャリアとト
ナーの混合攪拌、現像剤中のトナー濃度の制御、キャリ
アの定期的交換等の必要があるが、これらを解消すべく
、樹脂と磁性粉を主成分とする２〜５０μｍ程度の粒子
からなる一成分系の磁性トナーが提案されている。例え
ば米国特許第へ６５９゜２４５号明細誉にはトナー粒子
の表面にカーボンブラックなどの導電性粒子を埋め込ん
だ導を率が１０−′〜１Ｏ−ＩＩ　Ω・副の範囲にある
導電性磁性トナーが記載されている。また特開昭５１−
１２６８３４号公報には、トナー粒子の表面に平均粒径
が３μｍ以下好ましくは［１１μｍ以下の微粒子、例え
ば水溶性又は油溶性の染料微粉末、顔料微粉末、カーボ
ンブラック微粉末など００１〜２　ｗｔ％を静電吸引力
によって保持した磁性トナーが記載されている。However, when using a two-component developer, it is necessary to mix and stir the carrier and toner, control the toner concentration in the developer, and periodically replace the carrier. A one-component magnetic toner consisting of particles of approximately 2 to 50 μm in size and mainly composed of is proposed. For example, U.S. Pat. No. 659.245 discloses a conductive magnetic toner having conductive particles such as carbon black embedded in the surface of the toner particles and having a conductivity in the range of 10-' to 1 O-II Ω.sub. is listed. Also, JP-A-51-
Publication No. 126834 discloses that on the surface of toner particles, fine particles having an average particle size of 3 μm or less, preferably 11 μm or less, such as water-soluble or oil-soluble dye fine powder, pigment fine powder, carbon black fine powder, etc. A magnetic toner is described in which the magnetic toner is held by electrostatic attraction.

マタ特開昭５１−１０１５３５号公＠ｔｉｃ　Ｈ：、ト
ナー粒子の表面にＳｉＯっ、Ｔｉｅ、、、ＡＩ！０．　
等の流動性改質剤微粉末をＩ１２〜３０ｗｔ％混合した
磁性トナーが記載されている。Mata JP-A-51-101535 @tic H:, SiO, Tie, AI! on the surface of toner particles! 0.
A magnetic toner in which 12 to 30 wt % of a fluidity modifier fine powder such as I is mixed is described.

一成分系の磁性トナーを用いた現縁方法は、例えば特公
昭５６−２７９５号公報に記載されている。この現像方
法は、前記米国特許に記載されている如くの導電性磁性
トナーを導電性スリーブ上に磁気的に保持し、導電性磁
性トナーを介して導電性スリーブと静電潜像面との間に
導電路を形成せしめている。この公告公報には、上記導
電性スリーブに直流バイアス電位を加え、このバイアス
′亀位を変化させることによって反転現像がイ→られる
ことが記載されている。またその実施例２には導電性ス
リーブに帯電領域の表面電位と略吾しいバイアス電圧を
印加することが示されているが、この方法では静′亀宿
像の表面電位の影響を受けや４　・ すく安定性に難点がある。A current edge method using a one-component magnetic toner is described, for example, in Japanese Patent Publication No. 56-2795. This developing method magnetically holds a conductive magnetic toner on a conductive sleeve as described in the above-mentioned U.S. patent, and connects the conductive sleeve and the electrostatic latent image surface via the conductive magnetic toner. A conductive path is formed between the two. This publication describes that reversal development can be achieved by applying a direct current bias potential to the conductive sleeve and changing the bias position. Further, in Example 2, it is shown that a bias voltage that is approximately equal to the surface potential of the charged region is applied to the conductive sleeve, but this method is not affected by the surface potential of static images.・ There is a problem with stability.

そこで反転画像を得る場合、通常は帯電領域の表面電位
よりやや高いバイアス電圧が設定されている。しかして
、反転現像の実施においては、湿度、温度等の環境条件
の変化により画質が大きく変化することから、特に湿度
を考慮してバイアス電圧を調整している。すなわち従来
の反転現像では、環境条件に応じたバイアス電圧の調整
が必要であり、実用性に欠けるという問題がある。Therefore, when obtaining an inverted image, a bias voltage that is slightly higher than the surface potential of the charged area is usually set. However, in implementing reversal development, the image quality changes greatly due to changes in environmental conditions such as humidity and temperature, so the bias voltage is adjusted with particular consideration to humidity. That is, in conventional reversal development, it is necessary to adjust the bias voltage depending on the environmental conditions, and there is a problem that it lacks practicality.

本発明の目的は、上述の従来技術の問題点を解消し、高
品質の反転画像が得られるバイアス電圧の許容範囲が広
く、環境変化に対する安定性の高い現像方法を提供する
ことである。SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a developing method that provides a high-quality inverted image, has a wide bias voltage tolerance range, and is highly stable against environmental changes.

本発明の他の目的は、反転現像のみならず正規現像も可
能な現像方法を提供することである。Another object of the present invention is to provide a developing method that allows not only reversal development but also regular development.

本発明の現像方法は、帯電領域と非帯電領域からなる静
電潜像を保持してなる負の帯電特性を有する記録層に対
向して、内部に磁界発生手段を有する非磁性材料からな
如、少へとも表面が導電性でおるスリーブを配置し、該
スリーブ上に磁性トナーを供給し、前記磁界発生手段と
導電性スリーブを相対的に移動させることにより前記記
録層と導電性スリーブとの間に形成された現像領域に向
かって磁性トナーを搬送させ、前記導電性スリーブを接
地するかもしくは負極性のバイアス電圧を印加し、前記
現像領域において磁性トナーを前記帯電領域もしくは非
帯電領域に選択的に付着させてなる現像方法において、
体積抵抗が１０７〜１０′４Ω・清の範囲にありかつ、
未帯電の前記記録層に磁性トナーが付着し始める時の正
および負のバイアス電圧をそれぞれ■１および鴇とし、
かつ前記記録層の飽和電位を鬼とした場合に、ｌ　Ｖ、
Ｉ　＞　ＩＶ＋、１＞ＩＶ、ｌなる関係の帯電能力を有
する磁性トナーを用いることを％徴としている。The developing method of the present invention is directed to a recording layer made of a non-magnetic material having a magnetic field generating means inside, facing a recording layer having a negative charging characteristic and holding an electrostatic latent image consisting of a charged area and an uncharged area. , by disposing a sleeve whose surface is at least electrically conductive, supplying magnetic toner onto the sleeve, and moving the magnetic field generating means and the conductive sleeve relative to each other, the recording layer and the conductive sleeve are connected to each other. The magnetic toner is transported toward a developing area formed between the two, and the conductive sleeve is grounded or a negative bias voltage is applied, and the magnetic toner is selected in the charged area or the uncharged area in the developing area. In a developing method in which
The volume resistivity is in the range of 107 to 10'4 Ω, and
Let the positive and negative bias voltages at which magnetic toner starts to adhere to the uncharged recording layer be 1 and 1, respectively,
And when the saturation potential of the recording layer is set as a demon, lV,
The percentage characteristic is to use a magnetic toner having a charging ability of the relationship I>IV+, 1>IV, l.

以下本発明の詳細を図面により説明する。The details of the present invention will be explained below with reference to the drawings.

第１図は本発明の反転現像方法の機構を説明するための
現像部の断面模式図、第２〜５図はバイアス電圧とトナ
ーの付着量との関係を示す図、第６図は環境条件と画質
との関係を示す図である。Figure 1 is a schematic cross-sectional view of the developing section for explaining the mechanism of the reversal developing method of the present invention, Figures 2 to 5 are diagrams showing the relationship between bias voltage and toner adhesion amount, and Figure 6 is the environmental conditions. FIG. 3 is a diagram showing the relationship between image quality and image quality.

まず第１図に関し、導電性基体１ｂ上に光導電性ノー１
１を形成してなる記録体１の表面上は一様帯電及び光像
の露光工８を経て静電潜像が形成される。この静電潜像
において、図中−記号で示す未露光部を帯電領域と称し
、一方最高露光を受けて電位が残留している部分を非帯
電領域と称して以下説明する。First, with regard to FIG. 1, a photoconductive no.
1, an electrostatic latent image is formed on the surface of the recording medium 1 through uniform charging and an optical image exposure step 8. In this electrostatic latent image, the unexposed area indicated by the symbol - in the figure will be referred to as a charged area, while the area that has been exposed to maximum light and has a residual potential will be referred to as an uncharged area, which will be described below.

上記記録体１との間に現像領域２を形成するために、記
録体１に対向して非磁性かつ導電性を有する円筒状のス
リーブ３が配置されてｂる。このスリーブ３は導電性基
体１ｂとバイアス電源６を介して結線されているととも
に、現像領域２における記録１−１ａの非帯電領域によ
り大きな電界が形成されるようにスリーブ６には静電Ｉ
Ｗ像と同極性（−）の電圧が印加されている。スリーブ
５上に供給された磁性トナー５は、スリーブ３の内部に
配置された複数個の磁極を有す不永久磁石４の磁気臥引
力によってスリーブ６上に保持される。In order to form a developing area 2 between the recording medium 1 and the recording medium 1, a non-magnetic and conductive cylindrical sleeve 3 is placed opposite the recording medium 1. This sleeve 3 is connected to the conductive substrate 1b via a bias power supply 6, and the sleeve 6 is charged with an electrostatic I.
A voltage of the same polarity (-) as the W image is applied. The magnetic toner 5 supplied onto the sleeve 5 is held on the sleeve 6 by the magnetic attraction force of the permanent magnet 4 having a plurality of magnetic poles arranged inside the sleeve 3 .

スリーブｓ上に吸着された磁性トナー５はスリーブ５と
永久磁石４の相対的回転、例えばスリーブ３を固定して
永久磁石４を図示矢印（Ｘ）方向に回転させることによ
シ鎖状に連なって図示矢印（ｙ）方向に搬送される。こ
の場合磁気ブラシ中の磁性トナーは微視的にみると鎖状
に連なっており、現像領域２に至る前のトナー鎖５ａは
中性に保たれている。次に現像領域２中のトナー鎖５ｂ
には、静電潜像の非帯電領域とスリーブ３との間に形成
された電界Ｅが作用するため、各トナー粒子の内部で電
界Ｅに沿って空間電荷の分離が始まり、各トナー粒子の
接触面に互いに反対極性の空間電荷が分布する。これの
空間電荷は、誘電分極による表面電荷と異なり、他の物
質へ自由に移動できるため、各トナー粒子の接触部にお
いて、逆極性の電荷が再結合しよってトナー鎖５ｂの先
端のトナーを靜ｔａ像と同極性に帯電させる。またトナ
ー鎖５ｂでは静電潜像と逆極性の電荷はスリーブ５に流
れてしまう。次にトナー鎖５ｃにおいても各トナー粒子
の内部での空間電荷の分離が続くことから、トナー鎖先
端のトナー粒子は一層強く帯電される。その結果このト
ナー粒子には電界Ｅにより静電潜像に向かう静電吸引力
が作用してこの静電吸引力が上記磁気吸引力に勝って非
帯電領域にトナーが付着すると考えられる０そして現像
領域２の外のトナー鎖５ｄは、電界Ｅの影響を受けない
ため再び電気的に中性化される０ 上記の反転現像において磁性トナーを非帯電領域に安定
かつ良好に付着させるべく種々検討した結果、次のよう
な条件で現像を行えば良好な結果が得られることを見い
だした。The magnetic toner 5 attracted onto the sleeve s is connected in a chain by relative rotation of the sleeve 5 and the permanent magnet 4, for example, by fixing the sleeve 3 and rotating the permanent magnet 4 in the direction of the arrow (X) shown in the figure. and is transported in the direction of the arrow (y) shown in the figure. In this case, the magnetic toner in the magnetic brush is microscopically linked in a chain, and the toner chain 5a before reaching the development area 2 is kept neutral. Next, the toner chain 5b in the development area 2
Since the electric field E formed between the uncharged area of the electrostatic latent image and the sleeve 3 acts on the , space charges begin to separate along the electric field E inside each toner particle, causing the separation of the space charges of each toner particle. Space charges of opposite polarity are distributed on the contact surface. Unlike the surface charge due to dielectric polarization, this space charge can freely move to other substances, so at the contact area of each toner particle, charges of opposite polarity recombine, thereby suppressing the toner at the tip of the toner chain 5b. It is charged to the same polarity as the ta image. Further, in the toner chain 5b, charges having a polarity opposite to that of the electrostatic latent image flow to the sleeve 5. Next, since separation of space charges within each toner particle continues in the toner chain 5c, the toner particle at the tip of the toner chain is more strongly charged. As a result, an electrostatic attraction force toward the electrostatic latent image acts on the toner particles due to the electric field E, and this electrostatic attraction force overcomes the magnetic attraction force, causing the toner to adhere to the uncharged area. The toner chains 5d outside area 2 are not affected by the electric field E and are therefore electrically neutralized again. In the above reversal development, various studies were conducted to make the magnetic toner adhere stably and well to the uncharged area. As a result, it was found that good results could be obtained if development was carried out under the following conditions.

まず、第１図において、記録体１として市販の酸化亜鉛
紙（飽和電位−４ｓ　ＯＶ）を用い、この酸化亜鉛紙を
未帯電のまま現像領域に搬送して、酸化亜鉛紙の表面を
トナーブラシで摺擦した場合のバイアス電圧とトナーの
付着量を求めたところ、第２図に示す結果が得られた。First, in FIG. 1, a commercially available zinc oxide paper (saturation potential -4s OV) is used as the recording medium 1. The zinc oxide paper is conveyed to the developing area in an uncharged state, and the surface of the zinc oxide paper is brushed with a toner brush. When the bias voltage and the amount of toner adhesion were determined when rubbing was performed, the results shown in FIG. 2 were obtained.

ここでスリーブは外径３２ｍｒｒｌｌのアルミニウム製
円筒を用い、永久磁石ロールは外径２９．５ｒｒＥｎダ
、８極対称着磁、スリーブ上の磁束密度が８００Ｇのバ
リウムフェライト磁石を用い、現像ギャップをｃＬ５５
ｎ′ｌｌＴ１１　　ドクターギャップを１４ｍｍに設定
した０またトナーは第１表に示すＡトナーを用いた。Here, the sleeve is an aluminum cylinder with an outer diameter of 32 mrrll, the permanent magnet roll is a barium ferrite magnet with an outer diameter of 29.5 mm, 8-pole symmetrical magnetization, and a magnetic flux density of 800 G on the sleeve, and the developing gap is cL55.
n'llT11 The doctor gap was set to 14 mm, and toner A shown in Table 1 was used.

第２図に示すように、バイアス電圧が増加しである値鬼
、■１に達するとトナーの付着が生じ、さらにバイアス
電圧を上げるとトナー付着量は急激に増加する。すなわ
ちバイアス電圧が鴇、■１に達するとトナーは非帯電領
域に付着するので、この時のバイアス電圧当および■１
を現像開始電圧と称する。しかしてＡトナーの場合は、
第２図に示すように記録体の飽和電位Ｖ＋５に対して、
ＩＶ、ｌ＞１ｖ、１、ＩＶ−１ｌ：ｅる関係に６す、ｌ
　Ｖ、　Ｉｌｌ　Ｖ−、ｌ　−ｃあるため、トナーは正
及び負に帯電しゃすい。したがってこのようなトナーを
用いて反転現像を行うと、非帯電領域へのトナーの付着
が小さな電界により生じやすくなる。As shown in FIG. 2, when the bias voltage increases and reaches a certain value (1), toner adhesion occurs, and when the bias voltage is further increased, the amount of toner adhesion increases rapidly. In other words, when the bias voltage reaches 1, the toner adheres to the uncharged area, so the bias voltage and 1
is called the development start voltage. However, in the case of A toner,
As shown in FIG. 2, for the saturation potential V+5 of the recording medium,
IV, l>1v, 1, IV-1l: 6s, l in the relationship
Since V, Ill V-, l-c, the toner is charged positively and negatively. Therefore, when reversal development is performed using such toner, toner tends to adhere to uncharged areas due to a small electric field.

第　　　１　　　表 １ なお第１表において、樹脂はワックス（三井石゛油化学
製ハイワックス２０（ＩＰ）とエチレン酢酸ビニル共重
合体（アライドケミカル族ＡＣ４ｏ　ｏ）を重蓋比で７
＝３に混合したもの、磁性粉はマグネタイト　（戸田工
業製ＥＰＴ５００）、カーボンブラックは三菱化成製す
４４．５ｉｎｓはエロジル１８０（日本エアロジル製）
を使用して、次のようにしてトナーを調整した。Table 1 In Table 1, the resin is a mixture of wax (Mitsui Stone Oil Chemicals Hiwax 20 (IP)) and ethylene-vinyl acetate copolymer (allied chemical group AC4o) at a weight ratio of 7.
Magnetic powder is magnetite (EPT500 manufactured by Toda Kogyo), carbon black is manufactured by Mitsubishi Kasei, and 44.5ins is Erosil 180 (manufactured by Nippon Aerosil).
I adjusted the toner as follows using:

すなわちまず樹脂と磁性粉を乾式混合した後１５０°０
で加熱混練し、次いで冷却固化後粉砕した。次１に粉砕
粉を２００°０の熱気流中に導入して球状化処理を行っ
た後カーボンブラック又はカーボンブラックと５ｉｎｓ
を添加混合し、次いで分級した。トナーの抵抗は、内径
５−ｔＪ５ｒｒｒｎｌの絶縁シリンダー中にトナー粉末
を１Ｄ〜２０ｒｌＴＨの高さに充填し、（約１ｏｏｇＯ
荷重下、Ｄ　、　Ｃ１０ｏｖ／ａｓｏ電場で測定した。That is, first, after dry mixing the resin and magnetic powder,
The mixture was heated and kneaded, then cooled and solidified, and then pulverized. Next, the pulverized powder is introduced into a hot air stream at 200°0 to perform a spheroidization treatment, and then mixed with carbon black or carbon black for 5ins.
were added and mixed, and then classified. The resistance of the toner is determined by filling an insulated cylinder with an inner diameter of 5-tJ5rrrnl with toner powder to a height of 1D to 20rlTH (approximately 10ogO
Measured under load, D, C10ov/aso electric field.

次に第１表のＢ−Ｅのトナーを用いて、上記と同様の実
験を行ったところ、第５図に示す結果が得られた。第５
図に示すように、トナーの表面に１２　。Next, an experiment similar to the above was conducted using toners B to E in Table 1, and the results shown in FIG. 5 were obtained. Fifth
12 on the surface of the toner as shown in the figure.

添加するカーボンブラックの量が増加するにつれて現像
開始電圧ＶＬｔが増加することがわかる。すなわちトナ
ーが負に帯電しやすくするためには、カーボンブラック
の添加量を減少させればよい。It can be seen that as the amount of carbon black added increases, the development start voltage VLt increases. That is, in order to easily charge the toner negatively, the amount of carbon black added may be reduced.

次に第１表のＦ−Ｈのトナーを用いて、上記と同様の実
験を行ったところ第４図に示す結果が得られた。第４図
に示すように、トナーの表面に添加する８１０２粒子の
添加量が増加するにつれて、現像開始電圧の絶対値ＩＶ
−ｔｌおよびｌＶ＋ｔｌはいずれも増加するとともにｌ
　Ｖ−Ｈｌの増加分がＩＶ−ｔｌの増加分よりも大とな
ることがわかる。また５ｔＯ２の他れはこれら流動性改
質剤は低湿時に脱水してトナー粒子を負に帯電させ、よ
ってトナーの電荷量が・増加するからであると考えられ
る。Next, an experiment similar to the above was conducted using toners F-H in Table 1, and the results shown in FIG. 4 were obtained. As shown in FIG. 4, as the amount of 8102 particles added to the toner surface increases, the absolute value of the development start voltage IV
-tl and lV+tl both increase and l
It can be seen that the increase in V-Hl is larger than the increase in IV-tl. In addition to 5tO2, it is believed that these fluidity modifiers dehydrate at low humidity and negatively charge the toner particles, thereby increasing the charge amount of the toner.

第２〜４図に示す結果から、酸化亜鉛紙の如くの負帯電
型の感光体に対しては第５図に示すような帯！特性を有
するトナーを用いることにより良好な反転現象が得られ
る。すなわちＩ　Ｖ−ｔ　ｌ　＜　ｌｖ＋。From the results shown in FIGS. 2 to 4, it can be seen that for a negatively charged photoreceptor such as zinc oxide paper, the band shown in FIG. 5! A good reversal phenomenon can be obtained by using a toner having such characteristics. That is, I V-t l < lv+.

１＜ＩＶ、ｌなる条件を満たすトナーは、トナーが負に
強く帯電しやすく、良好な反転画像が得られるＯ またトナーの抵抗は低すぎるとトナーがブラシの運動に
より帯電しにくくなって反転現像に問題を生じ、高すぎ
ると帯電領域への付着に問題を生じる。すなわち、正規
現像が困難となる０したがって本発明で使用するトナー
の抵抗は１０拳〜１０１チΩ・１１好ましくは１０１０
〜１０１１Ω・鏝の範囲がよい。Toner that satisfies the condition 1<IV, l is easily charged strongly negatively, and a good reversal image can be obtained.In addition, if the resistance of the toner is too low, the toner becomes difficult to be charged by the movement of the brush, resulting in reversal development. If it is too high, it will cause problems with adhesion to charged areas. That is, the resistance of the toner used in the present invention is 10 to 101 Ω·11, preferably 1010, which makes regular development difficult.
A range of ~1011Ω/trowel is preferable.

またトナーが上町のような帯電特性を有するためには、
カーボンブラックの添加量を０〜ａ、ａ％の範囲で選択
することが好ましい。これはカーボンブラックは添加量
が多すぎるとＩＶ＋ｓ＋の値が大きくなり却って負に帯
電しにくくなるからでわるく、１．　Ｏｗｔチを超える
とＩＶ＋ｔｌと１−１との差が小さくなるからでわる０
なおり−ボンプラックは無添加でも流動性改質剤の添加
量の調整によって上記条件を満たすことができる。In addition, in order for the toner to have charging characteristics like Kamimachi,
It is preferable to select the amount of carbon black added in the range of 0 to a.a.%. This is bad because if the amount of carbon black added is too large, the value of IV+s+ will increase, making it difficult to be negatively charged.1. This occurs because the difference between IV+tl and 1-1 becomes smaller when Owt is exceeded.
Naori-Bonplak can satisfy the above conditions even without additives by adjusting the amount of the fluidity modifier added.

次に第１表のＡトナーとＨトナーを用いて、第１図にお
いて、記録体として酸化亜鉛紙を用い、−４５０Ｖに一
様帯電後霧光して、種々の環境条件の下で画像作成実験
を行ったところ、第６図に示す結果が得られた。第６図
において、実線はＡトナーの場合の良好な反転画像が得
られる範囲、そして破線はＨトナーで良好な反転画像が
得られる範囲を示している。Next, using toner A and toner H shown in Table 1, images were created under various environmental conditions by using zinc oxide paper as a recording medium, uniformly charging it to -450V, and fogging it as shown in Figure 1. When the experiment was conducted, the results shown in FIG. 6 were obtained. In FIG. 6, the solid line shows the range in which a good reversed image can be obtained with the A toner, and the broken line shows the range in which a good reversed image can be obtained with the H toner.

第６図から、従来のＡトナーでは良好な画像が得られる
バイアス範囲は極めて狭く、各環境毎にバイアス電圧を
調整する必要があることがわかる。From FIG. 6, it can be seen that the bias range in which a good image can be obtained with the conventional A toner is extremely narrow, and it is necessary to adjust the bias voltage for each environment.

これに対して本発明のトナーでは良好な画像が得られる
バイアス電圧は極めて広＜、６［１％ＲＨ％３０℃まで
はバイアス電圧が同一でも良好な画像が得られる。On the other hand, with the toner of the present invention, the bias voltage at which good images can be obtained is extremely wide.

さらに、上記Ｈトナーを用いて、スリーブを接地して、
上記同様の条件で現像を行ったところ、濃度１．３、解
像度１０本／ｍｍ以上の良好な画像が得られた。Furthermore, using the above H toner, ground the sleeve,
When development was performed under the same conditions as above, a good image with a density of 1.3 and a resolution of 10 lines/mm or more was obtained.

以上に記述の如く、本発明によれば、高品質の反転現像
が得られるバイアス電圧の許容範囲が広くて安定した現
像を行うことができ、かつ正規現像も可能であるという
優れた効果が得られるものである。As described above, according to the present invention, excellent effects are obtained in that high-quality reversal development can be achieved with a wide bias voltage tolerance range, stable development can be performed, and regular development is also possible. It is something that can be done.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は反転現像の原理を説明するための現像部の断面
図、第２図は従来のトナーを用いた場合のバイアス電圧
とトナーの付着量との関係を示す図、第３図および第４
図はカーボンブラックおよび５ｉｎｓをパラメータとし
た場合のバイアス電圧とトナーの付着量との関係を示す
図、第５図は本発明のトナーのバイアス電圧とトナーの
付着量との関係を示す図、第６図はバイアス電圧と環境
条件との関係を示す図である。 １：記録体、２：現像領域、３ニスリーブ、４：永久磁
石、５：磁性トナーFigure 1 is a cross-sectional view of the developing section to explain the principle of reversal development, Figure 2 is a diagram showing the relationship between bias voltage and toner adhesion amount when conventional toner is used, Figures 3 and 3 are diagrams showing the relationship between bias voltage and toner adhesion amount when conventional toner is used. 4
The figure shows the relationship between the bias voltage and the toner adhesion amount when carbon black and 5ins are used as parameters. FIG. 6 is a diagram showing the relationship between bias voltage and environmental conditions. 1: Recording body, 2: Development area, 3 Ni sleeve, 4: Permanent magnet, 5: Magnetic toner

Claims (1)

【特許請求の範囲】 １、　帯電領域と非帯電領域からなる静電潜像を保持し
てなる負の帯電特性を有する記録層に対向して、内部に
磁界発生手段を有する非磁性材料からなる導電性スリー
ブを配置し、該導電性スリーブ上に磁性トナーを供給し
、前記磁界発生手段と導電性スリーブを相対的に移動さ
せることにより前記記録層と導電性スリーブとの間に形
成された現像領域に向って磁性トナーを搬送させ、前記
導電性スリーブに０を含む負極性のバイアス電圧を印加
し、前記現像領域において磁性トナーを前記帯電領域も
しくは非帯電領域に選択的に付着させてなる現像方法に
おいて、体積比抵抗が１０゛テ〜１ｏ゛４Ω・傷の範囲
にあるとともに、未帯電の前記記録層に磁性トナーが付
着し始める時の正および負のバイアス電圧をそれぞれ看
およびＶ□としかつ前記記録層の飽和電位ｔ　Ｖ、トＬ
ｉ場合Ｋ　Ｉ　Ｖ、ｌ　＞　ｌ　Ｖ＋ｉ＋　カッｌ　Ｖ
＋ｔｌ＜　＋　Ｖ＋ｓ＋　＜　＋　ｖ、ｔなる関係を満
たす帯電能力を有する磁性トナーを用いることを特徴と
する現像方法。 ２　体積比抵抗が１０１１〜１０すΩ・藻の範囲にある
磁性トナーを用い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。 工ａＣ録層として光導電性酸化亜鉛をバインダー樹脂中
に分散させた層を用いることを特徴とする特許請求の範
囲第２項記載の現像方法。[Claims] 1. A recording layer made of a non-magnetic material and having a magnetic field generating means therein, facing a recording layer having a negative charging characteristic and holding an electrostatic latent image consisting of a charged area and an uncharged area. A developed image is formed between the recording layer and the conductive sleeve by arranging a conductive sleeve, supplying magnetic toner onto the conductive sleeve, and relatively moving the magnetic field generating means and the conductive sleeve. Development in which magnetic toner is conveyed toward a region, a bias voltage of negative polarity including 0 is applied to the conductive sleeve, and magnetic toner is selectively attached to the charged region or the uncharged region in the development region. In the method, the volume resistivity is in the range of 10° to 1°4Ω scratches, and the positive and negative bias voltages at which magnetic toner begins to adhere to the uncharged recording layer are set as V and V, respectively. and the saturation potential tV, tL of the recording layer
If i, K I V, l > l V+i+ Ka l V
A developing method characterized by using a magnetic toner having a charging ability that satisfies the relationship: +tl<+V+s+<+v, t. 2. The developing method according to claim 1, wherein a magnetic toner having a volume resistivity in the range of 10 11 to 10 ohms is used. 3. The developing method according to claim 2, wherein a layer in which photoconductive zinc oxide is dispersed in a binder resin is used as the aC recording layer.