JPS59162563A - Mangetic developer for developing electrostatic latent image - Google Patents
Mangetic developer for developing electrostatic latent imageInfo
- Publication number
- JPS59162563A JPS59162563A JP58037165A JP3716583A JPS59162563A JP S59162563 A JPS59162563 A JP S59162563A JP 58037165 A JP58037165 A JP 58037165A JP 3716583 A JP3716583 A JP 3716583A JP S59162563 A JPS59162563 A JP S59162563A
- Authority
- JP
- Japan
- Prior art keywords
- carrier
- magnetic
- toner
- developer
- particle size
- 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
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G9/00—Developers
- G03G9/08—Developers with toner particles
- G03G9/083—Magnetic toner particles
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G9/00—Developers
- G03G9/08—Developers with toner particles
- G03G9/10—Developers with toner particles characterised by carrier particles
- G03G9/107—Developers with toner particles characterised by carrier particles having magnetic components
- G03G9/108—Ferrite carrier, e.g. magnetite
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Developing Agents For Electrophotography (AREA)
Abstract
Description
【発明の詳細な説明】
本発明は静電潜像現像用磁性現像剤、具体的には、絶縁
性トナーをキャリアによって摩擦帯電させる一方、主と
して、磁石の回転により必要に応じては現像スリーブの
回転を伴い、トナーと磁性キャリアとからなる磁性現像
剤によって磁気刷子を形成すると共に磁気的に搬送し、
それを静電潜像担体表面に摺擦させることにより該担体
表面に担持された静電潜像を現像するーいわゆる磁気刷
子現像法において使用される2成分系磁性現像剤に関す
る。DETAILED DESCRIPTION OF THE INVENTION The present invention provides a magnetic developer for developing an electrostatic latent image, specifically, an insulating toner is triboelectrically charged by a carrier, and a developing sleeve is charged by rotation of a magnet as necessary. With rotation, a magnetic developer consisting of toner and magnetic carrier forms a magnetic brush and is transported magnetically.
The present invention relates to a two-component magnetic developer used in the so-called magnetic brush development method, in which an electrostatic latent image carried on the surface of an electrostatic latent image carrier is developed by rubbing it on the surface of the carrier.
従来、この種の磁性現像剤としては、平均粒径100〜
200μm程度の鉄粉等からなる磁性キャリアと、平均
粒径10〜20μm程度の絶縁性トナーとを混合してな
る現像剤が知られているが、この様な現像剤では特にト
ナーとキャリアとの混合比を精度良く一定に維持してお
かなければ良質な現像画像が安定して得られず−しかも
混合比の適正範囲が狭いため使用時に適正な混合比に維
持することが困難であること、また長期使用によってキ
ャリア表面にトナーが融着してキャリアが劣化するため
、周期的に現像剤を新しいものと交換 ・しなければな
゛らず、保守に多大の工数を要し、かつ不経済であるこ
と、さらに、現像画像中にカブ、りを生じ易く画像の解
像度も低いなどの欠点を伴うものであった。このため、
これらの欠点の改善された現像剤として、近年、特開昭
55−3:ll’0に3号公報にて、鉄粉キャリアの代
りに、バインダ樹脂中に磁性微粉末を分散させてなる平
均粒径5〜40μm程度の絶縁性磁性粒子をキャリアと
して使用した現像剤が提案されるに至っている。Conventionally, this type of magnetic developer has an average particle size of 100~
A developer is known that is made by mixing a magnetic carrier made of iron powder or the like with a diameter of about 200 μm and an insulating toner with an average particle size of about 10 to 20 μm. Unless the mixing ratio is kept constant with high precision, high-quality developed images cannot be stably obtained - and since the appropriate mixing ratio range is narrow, it is difficult to maintain the appropriate mixing ratio during use. In addition, due to long-term use, toner adheres to the carrier surface and the carrier deteriorates, making it necessary to periodically replace the developer with a new one, which requires a large amount of maintenance work and is uneconomical. In addition, there were other drawbacks such as fogging and smearing easily occurring in the developed image and the resolution of the image being low. For this reason,
In recent years, as a developing agent that has improved these drawbacks, Japanese Patent Application Laid-open No. 3/1983 (1989-3: ll'0) has proposed a developer in which fine magnetic powder is dispersed in a binder resin instead of an iron powder carrier. Developers using insulating magnetic particles with a particle size of about 5 to 40 μm as carriers have been proposed.
この現像剤は、前記の如き欠点のいくつかはキャリア自
体の粒径を小粒径化することによって改善され得るであ
ろうとの認識の下に開発されたものである。なお1、鉄
粉等を25〜60μm程度に小粒径化し、これをキャリ
アとして使用した場合、磁気刷子形成時にキャリア間で
生じる磁気吸引力が強磁きて、各キャリアが磁気刷子担
体上で連鎖状もしくはフィン状に凝集し、これが現像剤
の搬送障害となり、ソリッド状の現像画像中に白スジ等
のトラブルを発生させるため実用できない。このため、
前記提案された現像剤においては、微細な鉄粉等の磁性
微粉末をバインダ樹脂中に分散させてなる、いわゆるバ
インダ型磁性粒子がキャリアとして使用されている。従
って一前記キャリア間の磁気吸引力は弱められ、磁気刷
子担体上でのキャリアの凝集は防止されると共に、ソフ
トな刷子の穂が形成され、その結果、良好な画質の現像
画像が得られることとなる。しかし、この現像剤におい
ては、バインダとしての樹脂の存在によって磁性キャリ
アの磁化が弱められているため、帯電量の高いトナーが
使用されている場合、トナーとの摩擦帯電によりキャリ
ア自体の帯電量も増大することから、該キャリアに作用
する電気吸引力(静電潜像担体の非画像部に吸引される
力)が増大し、特に静電潜像担体表面上の画像周囲の電
界反転部にキャリアが付着する現象も発生し、現像画像
中の下地カブリとなり現像画像の画質を低下させるとい
う問題が往々にして生じ得る。This developer was developed based on the recognition that some of the above-mentioned drawbacks could be improved by reducing the particle size of the carrier itself. Note 1. When iron powder or the like is reduced in particle size to about 25 to 60 μm and used as a carrier, the magnetic attraction force generated between the carriers during magnetic brush formation becomes strong, and each carrier is attached to the magnetic brush carrier. It is not practical because it aggregates in chains or fins, which impedes the conveyance of the developer and causes problems such as white streaks in solid developed images. For this reason,
In the proposed developer, so-called binder-type magnetic particles, which are made by dispersing fine magnetic powder such as fine iron powder in a binder resin, are used as carriers. Therefore, the magnetic attractive force between the carriers is weakened, and aggregation of the carriers on the magnetic brush carrier is prevented, and soft brush ears are formed, resulting in a developed image of good quality. becomes. However, in this developer, the magnetization of the magnetic carrier is weakened by the presence of resin as a binder, so if a toner with a high charge amount is used, the charge amount of the carrier itself will decrease due to frictional charging with the toner. As a result, the electric attractive force acting on the carrier (the force attracted to the non-image area of the electrostatic latent image carrier) increases, and the carrier is particularly attracted to the electric field reversal area around the image on the surface of the electrostatic latent image carrier. The phenomenon of adhesion of the toner may also occur, which often causes the problem of forming a base fog in the developed image and deteriorating the image quality of the developed image.
本発明は、前記の様な問題に鑑みてなされたもので、ソ
リッド状の現像画像中に白スジを生じたり、あるいは下
地カブリを生じることがなく、極めて良好な画質の現像
画像を得ることのできる現像剤を提供することを目的と
するものである。そして、その要旨は、絶縁性トナーと
磁性キャリアとからなる静電潜像現像用磁性現像剤にお
いて、前記トナーが樹脂と磁性微粉末を倉荷してなると
共に略60エルステッド以上の保磁力を有する磁性トナ
ーであり、一方、前記・キャリアが平均粒径15〜45
μmの強磁性体キャリアであって、該キャリアと前記ト
ナーとが重量比90:10〜60:40で混合されてい
ることにある。The present invention has been made in view of the above-mentioned problems, and it is possible to obtain developed images of extremely good quality without causing white streaks or background fog in solid developed images. The purpose of this invention is to provide a developer that can be used. The gist is that in a magnetic developer for developing electrostatic latent images consisting of an insulating toner and a magnetic carrier, the toner is composed of a resin and a magnetic fine powder and has a magnetic coercive force of approximately 60 Oe or more. toner, while the carrier has an average particle size of 15 to 45
The present invention is a ferromagnetic carrier having a diameter of .mu.m, in which the carrier and the toner are mixed at a weight ratio of 90:10 to 60:40.
、すなわち、本発明は、強磁性体からなるキャリアの持
つ利点、具体的には、磁化が強くその帯電量が大きくな
っても静電潜像担体の非画部には付着せず、下地カブリ
を発生しないという利点を生かしつつ、磁化が大き過ぎ
ることに起因する問題、具体的には、キャリア自体が各
キャリア相互間で生じる強い磁気吸引力によって凝集し
、現像剤の磁気搬送性に悪影響を与え、ソリッド状の現
像画像中に白スジ等を発生させるという問題を−トナー
の2合比を高めると共に一特定の保磁力を有する磁性ト
、ナーの使用によって解決したものである。That is, the present invention has the advantages of a carrier made of ferromagnetic material, specifically, it has strong magnetization and does not adhere to the non-image area of the electrostatic latent image carrier even if the amount of charge increases, and the underlying fogging is prevented. While taking advantage of the advantage of not generating magnetic flux, we are solving problems caused by too large magnetization. Specifically, the carriers themselves aggregate due to the strong magnetic attraction force generated between each carrier, which adversely affects the magnetic transportability of the developer. The problem of white streaks and the like occurring in a solid developed image is solved by increasing the toner ratio and using a magnetic toner having a specific coercive force.
ここで、絶縁性トナーとじて略6oエルステッド以上の
保磁力を有する磁性トナーを使用するのは、トナーが磁
性を持たない場合、強磁性体キャリアに対し、トナーの
混和性が極めて悪く両者が分離してしまい、キャリアの
凝集による前記白スジか発生する一方、トナーの摩擦帯
電性も悪くなり、その結果として著しいトナーの飛散が
生ずることとなるからである。また、キャリアが磁性を
持つにも係わらず、その保磁力が略60エルステツドに
満たない場合にはキャリアに対するトナーの混和性が充
分に改善されず、キャリアの凝集による前記白スジが発
生し易いが、略6oエルステッド以上になると、混合性
が充分な程度にまで向上し、キャリアの磁気的凝集が阻
止され、さらに、ソフトな磁気刷子が形成されることと
なり、強磁、柱体キャリアの使用による前記問題を事実
」二解決できるからである。Here, the reason why a magnetic toner having a coercive force of about 6 o Oe or more is used as an insulating toner is that if the toner does not have magnetism, the miscibility of the toner with the ferromagnetic carrier is extremely poor and the two will separate. This is because, while the above-mentioned white streaks are generated due to carrier aggregation, the triboelectric charging properties of the toner are also deteriorated, and as a result, significant toner scattering occurs. Furthermore, even though the carrier is magnetic, if its coercive force is less than about 60 oersted, the miscibility of the toner with the carrier will not be sufficiently improved, and the white streaks will likely occur due to agglomeration of the carrier. , approximately 6o Oersted or more, the mixing property is sufficiently improved, magnetic agglomeration of carriers is prevented, and a soft magnetic brush is formed. This is because the above problem can be actually solved.
また、キャリアとトナーとの混合比を重量比で90:1
0〜60:40、好ましくは、85:15〜70:30
としたのは、トナー混合比がlQwt%未満では前記保
磁力を有する磁性トナーであっても、キャリアの磁気的
凝集を、さらには前記白スジの発生を防止する効果が充
分に期待できないこと、及び現像スリーブからキャリア
への電荷注入が顕著に発生することとなるため−キャリ
アが感光体の表面へと静電吸着され易く何り、その結果
として感光体の表面に擦傷が生するからである。Also, the mixing ratio of carrier and toner is 90:1 by weight.
0-60:40, preferably 85:15-70:30
The reason for this is that if the toner mixing ratio is less than 1Qwt%, even a magnetic toner having the above-mentioned coercive force cannot be expected to be sufficiently effective in preventing magnetic aggregation of carriers and furthermore the generation of the above-mentioned white streaks. Also, significant charge injection from the developing sleeve to the carrier occurs - the carrier is likely to be electrostatically attracted to the surface of the photoreceptor, resulting in scratches on the surface of the photoreceptor. .
また一方、40W[%を超えるとトナー自体の摩擦帯電
性が悪くなり、トナー飛散、下地カブリ等が発生するか
らである。On the other hand, if it exceeds 40 W [%, the triboelectric charging properties of the toner itself will deteriorate, resulting in toner scattering, background fogging, etc.
さらに、強磁性体キャリアの平均粒径を15〜45μm
好ましくは、30〜40μmとしたのは、平均粒径が1
5μm未満では、キャリアの磁気力が弱くなることに起
因して、キャリアの感光体の表面への付着が阻止され難
くなり、その結果として感光体の表面に擦傷が生するか
らである。また一方、45μmを超えると、キャリアの
磁力が強くなることに起因して、現像スリーブ上で現像
剤が磁気的に凝集され易くなり、ソリッド状の現像画像
中に白スジ等が発生し、更には、現像剤中におけるトナ
ーの荷電性が悪化され、トナー飛散等に伴う下地カブリ
等も発生することとなるからである。Furthermore, the average particle size of the ferromagnetic carrier is 15 to 45 μm.
Preferably, the average particle size is 30 to 40 μm.
If the thickness is less than 5 μm, the magnetic force of the carrier becomes weak, making it difficult to prevent the carrier from adhering to the surface of the photoreceptor, resulting in scratches on the surface of the photoreceptor. On the other hand, if the diameter exceeds 45 μm, the magnetic force of the carrier becomes stronger, making it easier for the developer to be magnetically aggregated on the developing sleeve, causing white streaks etc. to occur in the solid developed image. This is because the chargeability of the toner in the developer is deteriorated, and base fog etc. occur due to toner scattering and the like.
本発明に係る磁性現像剤における絶縁性トナーは、バイ
ンダとしての樹脂と磁性微粉末とを含有する他、従来多
用されている絶縁性トナーと同様着色剤および必要に応
じて帯電制御剤等を含有することができるが、磁性微粉
末の含有量はトナー全体に対し5〜35W【%とするの
が好ましい。これは磁性微粉末が5wt%未満では十分
な磁気力を有するトナーを製造し難く、また、35wt
%を超えると現像自体に悪影響が及はされ、具体的には
、現像画像濃度が低下するからである。磁性微粉末とし
ては、従来現像剤中に使用されている各種磁性体の微粉
末を使用すれはよい。但し、強磁性体キャリアの材料と
しては、特に−フエライト、鉄粉、磁性酸化鉄などの強
磁性材が好適であ′る。なお、前記磁性微粉末の粒子形
状は、表面に凹凸のある不定形か好適である。また、バ
インダ樹脂としては、ポリスチレン、スチレン−アクリ
ル系樹脂、アクリル樹脂、エポキシ樹脂−弗素樹脂など
従来現像剤中に使用されている各種樹脂を使用すればよ
い。The insulating toner in the magnetic developer according to the present invention contains a resin as a binder and magnetic fine powder, and also contains a colorant and, if necessary, a charge control agent, etc., as in the case of insulating toners commonly used in the past. However, the content of the magnetic fine powder is preferably 5 to 35 W[%] based on the total toner. This is because it is difficult to produce a toner with sufficient magnetic force when the magnetic fine powder is less than 5 wt%, and when the magnetic fine powder is less than 5 wt%,
If it exceeds %, the development itself will be adversely affected, specifically, the density of the developed image will decrease. As the magnetic fine powder, fine powders of various magnetic substances conventionally used in developers may be used. However, as the material for the ferromagnetic carrier, ferromagnetic materials such as ferrite, iron powder, and magnetic iron oxide are particularly suitable. The particle shape of the magnetic fine powder is preferably an amorphous shape with an uneven surface. Further, as the binder resin, various resins conventionally used in developers, such as polystyrene, styrene-acrylic resin, acrylic resin, and epoxy resin-fluororesin, may be used.
一方、磁石の回転により現像剤を磁気的に現像領域へと
搬送する形態の現像装置としては、特開昭54−119
935号公報、特開昭55−32073号公報等に開示
されるものを初めとして、その他種々のものが知られて
いるが、この様な形態の現像装置に限られることなく、
磁石(磁気ローラ)を内蔵する現像スリーブが固定され
た形態の、または、現像スリーブが磁石と同方向にある
いは逆方向に回転される形態の現像装置のいずれにも、
本発明に係る磁性現像剤は使用することができる。なお
、本発明に係る磁性現像剤は一前記の各現像装置との組
合せによって使用される場合において特に優れた効果を
示すものである。On the other hand, as a developing device in which the developer is magnetically conveyed to the developing area by rotating a magnet, there is
Various other developing devices are known, including those disclosed in Japanese Patent Application Laid-open No. 935 and Japanese Patent Application Laid-Open No. 55-32073, but are not limited to these types of developing devices.
A developing device in which a developing sleeve containing a magnet (magnetic roller) is fixed, or a developing device in which the developing sleeve is rotated in the same direction or in the opposite direction as the magnet,
The magnetic developer according to the present invention can be used. The magnetic developer according to the present invention exhibits particularly excellent effects when used in combination with each of the above-mentioned developing devices.
以下、本発明の実施例について説明する。Examples of the present invention will be described below.
実施例1
平均粒径0.5μmの酸化第2鉄63.3 wt%、平
均粒径Q、 l lLmの酸化亜鉛25.9 wt%お
よび平均粒径13μmの酸化ニッケル10.8wt%の
混合物3000yと水1195Fとを混合してスラリー
化し、これにポリメタクリル酸ナトリウム塩、ダーバン
7(商品名、アール ティ・パンデルビルト社製)の2
5W【%水溶液約98gを加えて混合した後、アトマイ
ザ−で噴霧乾燥し、次いで空気中1190℃で2時間焼
成して、平均粒径34.572mのフェライトキャリア
(組成:(NiO)o、3(ZnO)0.7(Fe20
3)。、8.)を得た。Example 1 3000y of a mixture of 63.3 wt% ferric oxide with an average particle size of 0.5 μm, 25.9 wt% zinc oxide with an average particle size Q, 11Lm, and 10.8 wt% nickel oxide with an average particle size of 13 μm and water 1195F to form a slurry, and to this slurry, polymethacrylic acid sodium salt and Durban 7 (trade name, manufactured by R.T. Pandelbilt) were added.
After adding and mixing about 98 g of 5W% aqueous solution, spray drying with an atomizer, and then baking in air at 1190°C for 2 hours to obtain a ferrite carrier with an average particle size of 34.572 m (composition: (NiO) o, 3 (ZnO)0.7(Fe20
3). , 8. ) was obtained.
またーこれ之は別に市販のスチレン・アクリル系樹脂1
00重量部、負帯電性染料T RH(商品名、係上ゲ谷
化学社製)4重量部および磁性微粉末として−マグネタ
イトKBC−100L(商品名、関東電化社製)20重
量部を150°Cで三本ロールにより混練し、冷却後へ
粉砕、分級して平均粒径11μmの絶縁性トナーを得た
。このトナーの保磁力は60エルステツドであった。Also, this is separately commercially available styrene/acrylic resin 1
00 parts by weight, 4 parts by weight of negatively chargeable dye T RH (trade name, manufactured by Kageya Kagaku Co., Ltd.) and 20 parts by weight of magnetite KBC-100L (trade name, manufactured by Kanto Denka Co., Ltd.) as magnetic fine powder at 150°C. The mixture was kneaded using three rolls, cooled, and then crushed and classified to obtain an insulating toner having an average particle size of 11 μm. The coercive force of this toner was 60 oersted.
前記キャリアとトナーとを重量比90:10で10、O
Lの代りにマクネタイト、E’1)T−100(商品名
、戸田工業社製)を用いた以外は同じ組成、方法により
、平均粒径11μm、保磁力110エルステツドの絶縁
性トナーを得た。このトナーを実流側1で得たキャリア
と10 :90の1重量比で混合し、磁性現像剤CB)
を調製した。The carrier and toner were mixed in a weight ratio of 90:10 and
An insulating toner having an average particle size of 11 μm and a coercive force of 110 oersted was obtained using the same composition and method except that manetite, E'1) T-100 (trade name, manufactured by Toda Kogyo Co., Ltd.) was used in place of L. This toner is mixed with the carrier obtained in the actual flow side 1 at a weight ratio of 10:90 to form a magnetic developer CB).
was prepared.
実施例3
実施例1において、磁性微粉末としてのWBC−10O
Lの代りにマグネタイト、RB−BL(商品名、チタン
工業社製)を用いた以外は同じ組成、方法により平均粒
径11μm、保磁力200エルステツドの絶縁性トナー
を雨、これを前記キャリアと10:90の重量比で混合
して磁性現像剤(C)を調製した。Example 3 In Example 1, WBC-10O as magnetic fine powder
An insulating toner with an average particle size of 11 μm and a coercive force of 200 oersted was mixed with the carrier for 10 to :90 weight ratio to prepare a magnetic developer (C).
実施例4
実施例1において、磁性微粉末としてのWBC−10O
Lの代りにマグネタイト、MTA−740(商品名、戸
田工業社製)を用いた以外は同じ組成、方法により平均
粒径11μm、保磁力350エルステツドの絶縁性トナ
ーを得、これを前記キャリアと10 :90の重量比で
混合して磁性現像剤(D)を調製した。Example 4 In Example 1, WBC-10O as magnetic fine powder
An insulating toner with an average particle size of 11 μm and a coercive force of 350 oersted was obtained using the same composition and method except that magnetite, MTA-740 (trade name, manufactured by Toda Kogyo Co., Ltd.) was used in place of L, and this was mixed with the carrier and :90 weight ratio to prepare a magnetic developer (D).
比較例1
実施例1において、磁性微粉末としてのKBC−100
Lの代りに鉄粉、MGMC(商品名、日本鉄粉社製)を
用いた以外は、同じ組成、方法により平均粒径11μm
−保磁力略0エルステツドの絶縁性トナーを得、これを
前記キャリアと10 : 90の重量比で混合して磁性
現像剤(E)を調製した。Comparative Example 1 In Example 1, KBC-100 as magnetic fine powder
The average particle size was 11 μm using the same composition and method except that iron powder, MGMC (trade name, manufactured by Nippon Tetsuko Co., Ltd.) was used instead of L.
- An insulating toner having a coercive force of approximately 0 oersted was obtained, and this was mixed with the carrier at a weight ratio of 10:90 to prepare a magnetic developer (E).
比較例2
実施例1で用いたスチレン・アクリル系樹脂100重量
部と、T RH4重量部と、カーボンブラックMA#8
(商品名、三菱化成工業社製)4重量部とから、実施例
1と同じ方法で平均粒径11μmの絶縁性トナー(非磁
性)を得、これを前記キャリアと10 :90の重量比
で混合して磁性現像剤(、F)を調製した。Comparative Example 2 100 parts by weight of the styrene/acrylic resin used in Example 1, 4 parts by weight of TRH, and carbon black MA#8
(trade name, manufactured by Mitsubishi Chemical Industries, Ltd.) by the same method as in Example 1 to obtain an insulating toner (non-magnetic) with an average particle size of 11 μm, and add this to the carrier at a weight ratio of 10:90. A magnetic developer (F) was prepared by mixing.
前記各現像剤をトナー像転写型電子写真複写機内の現像
装置(磁気ローラが現像剤搬送方向とは逆の方向に、現
像ローラが同じ方向に回転される形態の装置)中に装填
し、複写動作を繰返すこと°により復られる複写画像の
画質を調べた結果を第1表に示す。なお、前記現像装置
において、現像スリー;は感光体ドラムとの間に微少間
隙をおいて平行に配置され、かつ高速回転する磁気ロー
ラを内蔵するものである。ここで現像ス1ノープCt感
光体と逆方向に低速度で回転され、その内部の磁気ロー
ラは現像スリーブと逆方同番こ回転され、さらには、現
像スリーブに対して現像ノくイ・アスカ≦印加されてい
る。また、この現像装置におし1で、現像剤はバゲット
ローラによって混合攪拌され一トナーとキャリアとはお
互いに摩擦帯電されつつ、現像スリーブの周面上へと供
給される。ところで、前記複写機における静電潜像の現
像条件6ま次の通りである。Each developer is loaded into a developing device (a device in which a magnetic roller rotates in the opposite direction to the developer conveying direction and a developing roller rotates in the same direction) in a toner image transfer type electrophotographic copying machine, and copies are made. Table 1 shows the results of examining the image quality of the copied image restored by repeating the operation. In the above-mentioned developing device, the developing device 3 is arranged in parallel with the photosensitive drum with a small gap therebetween, and contains a magnetic roller that rotates at high speed. Here, the developing sensor 1 is rotated at a low speed in the opposite direction to the Ct photoconductor, and the magnetic roller therein is rotated at the same speed in the opposite direction to the developing sleeve. ≦ Applied. Further, in this developing device, the developer is mixed and agitated by a baguette roller, and the toner and carrier are mutually charged by friction and supplied onto the circumferential surface of the developing sleeve. By the way, conditions 6 for developing an electrostatic latent image in the copying machine are as follows.
磁%ローラ回転数−1、、OOOrPm現像スリーブ回
転数: 60 rPIn静電潜像最高電位:+400
V
現像バイアス電圧:+100V
第1表
第1表の結果から明らかなように、小粒径の強磁性体キ
ャリアを非磁性トナーとの組合せで用いた場合(現像剤
F)、白スジや下地カブリが発生し、また磁性トナーと
の組合せて用いた場合ごも保磁力が小さい場合(現像剤
E)には、下地カブリは防止できるものの白スジが発生
し、保磁力が60工ルステツド以上の磁性トナーと組合
せによって初めて白スジや下地カブリの発生が同時防止
できていることが判る。なお−この複写実験に関し、本
発明に係る現像剤(現像剤A〜D)では、市販の複写機
によって得られるものと比較して、非常にシャープで良
好な複写画像が得られることも別途確認されている。Magnetic % Roller rotation speed -1, OOOrPm Developing sleeve rotation speed: 60 rPIN electrostatic latent image maximum potential: +400
V Development bias voltage: +100V As is clear from the results in Table 1, when a small particle size ferromagnetic carrier is used in combination with a non-magnetic toner (developer F), white streaks and undercoat fogging occur. If the coercive force is small (developer E) when used in combination with a magnetic toner, white streaks will occur although background fogging can be prevented. It can be seen that the combination with toner can simultaneously prevent the occurrence of white streaks and background fog. Regarding this copying experiment, it was also separately confirmed that the developers according to the present invention (Developers A to D) were able to obtain very sharp and good copied images compared to those obtained by commercially available copying machines. has been done.
実施例5
実施例1で用意したフェライトキャリアと絶縁性トナー
とを用い−それらの混合比を第2表に示すように種々に
変えて磁性現像剤(A、G−J)を調製し、各現像剤を
用いて前記複写実験と同一の複写実験を行い−得られた
複写画像の画質を調べた。それらの結果を第2表に示す
。Example 5 Using the ferrite carrier and insulating toner prepared in Example 1, magnetic developers (A, G-J) were prepared by varying their mixing ratio as shown in Table 2. A copying experiment identical to the copying experiment described above was conducted using a developer and the quality of the resulting copied image was examined. The results are shown in Table 2.
第2表
第2表に示す結果から明らかなように、トナーの混合比
が5w(%では白スジか発生し、他方、60W【%では
トナーの摩擦帯電性が悪くなりトナーが充分な電荷を保
持し得ず、トナー飛散による上押カブリが発生すること
から、トナーの混合比は略10〜4 Q wt%の範囲
が適当であることが判る。また、この複写実験に関し、
この範囲では、特に現像剤Hが用いられた場合、白スジ
や下地カブリの発生がないことは勿論のこと一静電潜像
の非画像部へのキャリア付着も一切なく、画像濃度の高
い非常にシャープで良好な複写画像が得られることも別
途確認されている。Table 2 As is clear from the results shown in Table 2, when the toner mixing ratio is 5W (%), white streaks occur, while at 60 W (%), the triboelectric charging properties of the toner deteriorate and the toner does not have enough charge. Since the toner cannot be retained and top-press fog occurs due to toner scattering, it is found that the appropriate toner mixing ratio is in the range of approximately 10 to 4 Q wt%.In addition, regarding this copying experiment,
In this range, especially when developer H is used, not only will there be no white streaks or background fog, but there will be no carrier adhesion to the non-image areas of the electrostatic latent image, and the image density will be very high. It has also been separately confirmed that sharp and good quality copied images can be obtained.
実施例6
実施例1の場合と同一の方法に従い、第3表に示す平均
粒径のフェライトキャリアを得た。そして、各キャリア
を実施例1で得られたトナーと混合してトナー混合比1
0w【%の現像剤(K、N)を調製し、各現像剤を用い
て前記複写実験と同一の複写実験を行い、得られた複写
画像の画質を調べた。それらの結果を第3表に示す。Example 6 According to the same method as in Example 1, ferrite carriers having the average particle diameter shown in Table 3 were obtained. Then, each carrier was mixed with the toner obtained in Example 1 at a toner mixing ratio of 1.
0w% developers (K, N) were prepared, and a copying experiment identical to the copying experiment described above was conducted using each developer, and the image quality of the resulting copied images was examined. The results are shown in Table 3.
第゛3表
第3表および第1表の結果から明らかなように保磁力が
60工ルステツド以上のトナーとの組合せにおいて、キ
ャリアの粒径が少なくとも15〜45μmの範囲で良好
な画質の複写画像が得られることがわかる。なお、キャ
リアの平均粒径が45μmを超えた場合(現像剤N)白
スジが発生するのは、粒径の増大に伴いキヤ’Jア自体
の磁化が強くなり過ぎ、現像スリーブ上でキャリアの磁
気的凝集が発生し易くなることから、キャリアが磁気ロ
ーラの回転に追随して移動し難くなり、その結果−現像
剤自体の搬送が阻害されているからであると考えられる
。また、このことからも従来使用されている羊肉粒径1
00〜20011mの強磁性体キャリアは、磁石の回転
により現像剤を磁気的に現像領域へと搬送する形態の現
像装置において使用される磁性現像剤中のキャリアとし
て不適当であることかうかかわれる。また、この実験に
関しては、前記範囲内において、特に現像剤Mが用いら
れた場合、非常に良好な画質の現像画像が得られること
も別途確認されている。As is clear from the results in Table 3 and Table 1, when used in combination with a toner having a coercive force of 60 degrees or more, good image quality is obtained when the carrier particle size is at least in the range of 15 to 45 μm. It can be seen that the following can be obtained. Note that when the average particle size of the carrier exceeds 45 μm (developer N), white streaks occur because the magnetization of the carrier itself becomes too strong as the particle size increases, causing the carrier to form on the developing sleeve. This is thought to be because magnetic aggregation is more likely to occur, making it difficult for the carrier to move following the rotation of the magnetic roller, and as a result, the conveyance of the developer itself is inhibited. Also, from this, the conventionally used mutton particle size 1
It is said that the ferromagnetic carrier of 00 to 20011 m is unsuitable as a carrier in a magnetic developer used in a developing device in which the developer is magnetically conveyed to a developing area by rotation of a magnet. Further, regarding this experiment, it has been separately confirmed that within the above range, especially when developer M is used, a developed image of very good quality can be obtained.
比較例3
実施例1で用いたスチレン−アクリル系樹/+=100
重量部と、実施例3で用いたマクネタイトRB−BL2
Q′O重量部とを三本ロールで混練し、冷却後、粉砕、
分級して平均粒径11μmのいわゆるバインダ型磁性キ
ャリアを得た。このバインダ型磁性誹ヤリアを実施例1
で得た絶縁性トナーと第4表に示す混合比で混合して現
像剤(0−R)を調製し、各現像剤を用いて前記複写実
験と同一の複写実験を行い、得られた複写画像の画質を
調べた。それらの結果を第4表に示す。Comparative Example 3 Styrene-acrylic tree used in Example 1/+=100
Weight parts and macnetite RB-BL2 used in Example 3
Part by weight of Q'O is kneaded with three rolls, and after cooling, pulverization,
It was classified to obtain a so-called binder type magnetic carrier having an average particle size of 11 μm. Example 1 of this binder type magnetic carrier
A developer (0-R) was prepared by mixing with the insulating toner obtained in the mixing ratio shown in Table 4, and a copying experiment identical to the above copying experiment was conducted using each developer. I checked the image quality. The results are shown in Table 4.
第4表
第4表の結果から明らかなように、前記バインダ型磁性
キャリアを使用する現像剤においては一トナーの混合比
が低い場合には白スジやトナー飛散による下地カブリが
なく良好な複写画像が得られるものの現像されるべき静
電潜像の電位が+400■と比較的低いことに起因して
複写画像濃度が低く、しかもキャリアの非画像部への付
着は避けられず、また、画像濃度を高めるためにトナー
の混合比を高くすると、キャリアの付着量が急激に増大
し、いずれにせよ、良好な結果が得られ難いことが判る
。Table 4 As is clear from the results in Table 4, when the developer using the binder-type magnetic carrier has a low toner mixing ratio, there is no white streak or background fog due to toner scattering, resulting in good copied images. However, because the potential of the electrostatic latent image to be developed is relatively low at +400μ, the density of the copied image is low, and the adhesion of carrier to non-image areas is unavoidable, and the image density is low. It can be seen that when the toner mixing ratio is increased in order to increase the toner content, the amount of carrier adhesion increases rapidly, and in any case, it is difficult to obtain good results.
Claims (1)
現像用磁性現像剤において、前記トナーか樹脂と磁性微
粉末を含有してなると共に一路60エルステッド以上の
保磁力を有する磁性トナーであり、一方、前記キャリア
が平均粒径15〜45μmの強磁性体キャリアであって
、該キャリアと前記トナーとが重量比90 : 10〜
60:40で混合されていることを特徴とする静電潜像
現像用磁性現像剤。(1) A magnetic developer for developing an electrostatic latent image consisting of an insulating toner and a magnetic carrier, wherein the toner contains a resin and a magnetic fine powder and has a coercive force of 60 Oe or more. , on the other hand, the carrier is a ferromagnetic carrier with an average particle size of 15 to 45 μm, and the carrier and the toner have a weight ratio of 90:10 to
A magnetic developer for developing electrostatic latent images, characterized in that the mixture is mixed at a ratio of 60:40.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP58037165A JPS59162563A (en) | 1983-03-07 | 1983-03-07 | Mangetic developer for developing electrostatic latent image |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP58037165A JPS59162563A (en) | 1983-03-07 | 1983-03-07 | Mangetic developer for developing electrostatic latent image |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS59162563A true JPS59162563A (en) | 1984-09-13 |
Family
ID=12489980
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP58037165A Pending JPS59162563A (en) | 1983-03-07 | 1983-03-07 | Mangetic developer for developing electrostatic latent image |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS59162563A (en) |
Cited By (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS62100773A (en) * | 1985-10-29 | 1987-05-11 | Hitachi Metals Ltd | Developer for heat roll fixing |
JPH02101480A (en) * | 1988-10-11 | 1990-04-13 | Fuji Xerox Co Ltd | Image forming method |
US5053305A (en) * | 1988-09-07 | 1991-10-01 | Tdk Corporation | Composition and method for developing electrostatic latent images |
US5064739A (en) * | 1989-02-13 | 1991-11-12 | Hitachi Metals, Ltd. | Method of developing electrostatic charge pattern with magnetic developer |
JPH07311476A (en) * | 1991-05-24 | 1995-11-28 | Hitachi Ltd | Developer |
EP0701178A1 (en) | 1994-09-02 | 1996-03-13 | Mita Industrial Co. Ltd. | Image forming method |
EP0703503A1 (en) | 1994-08-31 | 1996-03-27 | Mita Industrial Co., Ltd. | Toner for a two-component type developer |
EP0703504A1 (en) | 1994-08-31 | 1996-03-27 | Mita Industrial Co., Ltd. | Toner for a two-component type developer |
EP0703505A1 (en) | 1994-08-31 | 1996-03-27 | Mita Industrial Co., Ltd. | Toner for two-component type developer |
EP0703507A1 (en) | 1994-09-02 | 1996-03-27 | Mita Industrial Co. Ltd. | Image forming method |
EP0703506A1 (en) | 1994-09-02 | 1996-03-27 | Mita Industrial Co. Ltd. | Method for developing an electrostatic latent image |
EP0704768A1 (en) | 1994-08-31 | 1996-04-03 | Mita Industrial Co., Ltd. | Toner for a two-component type developer |
EP0704767A1 (en) | 1994-08-31 | 1996-04-03 | Mita Industrial Co., Ltd. | A two-component type developer |
US5516613A (en) * | 1993-12-03 | 1996-05-14 | Hitachi Metals, Ltd. | Binary developer |
US7575839B2 (en) | 2005-03-31 | 2009-08-18 | Kyocera Mita Corporation | Magnetic toner for two-component developer and image forming method using the developer |
-
1983
- 1983-03-07 JP JP58037165A patent/JPS59162563A/en active Pending
Cited By (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS62100773A (en) * | 1985-10-29 | 1987-05-11 | Hitachi Metals Ltd | Developer for heat roll fixing |
JPH0431583B2 (en) * | 1985-10-29 | 1992-05-26 | ||
US5053305A (en) * | 1988-09-07 | 1991-10-01 | Tdk Corporation | Composition and method for developing electrostatic latent images |
JPH02101480A (en) * | 1988-10-11 | 1990-04-13 | Fuji Xerox Co Ltd | Image forming method |
US5064739A (en) * | 1989-02-13 | 1991-11-12 | Hitachi Metals, Ltd. | Method of developing electrostatic charge pattern with magnetic developer |
JPH07311476A (en) * | 1991-05-24 | 1995-11-28 | Hitachi Ltd | Developer |
US5516613A (en) * | 1993-12-03 | 1996-05-14 | Hitachi Metals, Ltd. | Binary developer |
EP0703504A1 (en) | 1994-08-31 | 1996-03-27 | Mita Industrial Co., Ltd. | Toner for a two-component type developer |
EP0703503A1 (en) | 1994-08-31 | 1996-03-27 | Mita Industrial Co., Ltd. | Toner for a two-component type developer |
EP0703505A1 (en) | 1994-08-31 | 1996-03-27 | Mita Industrial Co., Ltd. | Toner for two-component type developer |
EP0704768A1 (en) | 1994-08-31 | 1996-04-03 | Mita Industrial Co., Ltd. | Toner for a two-component type developer |
EP0704767A1 (en) | 1994-08-31 | 1996-04-03 | Mita Industrial Co., Ltd. | A two-component type developer |
US5580691A (en) * | 1994-08-31 | 1996-12-03 | Mita Industrial Co., Ltd. | Toner for a two-component type developer |
US5750301A (en) * | 1994-08-31 | 1998-05-12 | Mita Industrial Co., Ltd. | Toner for a two-component type developer |
EP0703507A1 (en) | 1994-09-02 | 1996-03-27 | Mita Industrial Co. Ltd. | Image forming method |
EP0703506A1 (en) | 1994-09-02 | 1996-03-27 | Mita Industrial Co. Ltd. | Method for developing an electrostatic latent image |
EP0701178A1 (en) | 1994-09-02 | 1996-03-13 | Mita Industrial Co. Ltd. | Image forming method |
US7575839B2 (en) | 2005-03-31 | 2009-08-18 | Kyocera Mita Corporation | Magnetic toner for two-component developer and image forming method using the developer |
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