JPH0651556A - Magnetic toner - Google Patents
Magnetic tonerInfo
- Publication number
- JPH0651556A JPH0651556A JP4202191A JP20219192A JPH0651556A JP H0651556 A JPH0651556 A JP H0651556A JP 4202191 A JP4202191 A JP 4202191A JP 20219192 A JP20219192 A JP 20219192A JP H0651556 A JPH0651556 A JP H0651556A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic toner
- toner
- magnetic
- agent
- dielectric loss
- 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.)
- Granted
Links
Landscapes
- Developing Agents For Electrophotography (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は複写機やレーザービーム
プリンターなどの電子写真装置に用いられる磁性トナー
に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic toner used in electrophotographic devices such as copying machines and laser beam printers.
【０００２】[0002]
【従来の技術】従来、電子写真法としては米国特許第２
２９７６９１、特公昭４２−２３９１０号公報、及び特
公昭４３−２４７４８号公報等で多種の方法が記載され
ている。一般には光導電性物質を利用して種々光学手段
により感光体上に電気的静電潜像を形成し、ついでこの
静電潜像をトナーを用いて可視像化し、必要に応じて紙
等に転写した後、加熱あるいは圧力等により定着し、コ
ピー画像を得るものである。2. Description of the Related Art Conventionally, US Pat.
Various methods are described in Japanese Patent Publication No. 297691, Japanese Patent Publication No. 42-23910, Japanese Patent Publication No. 43-24748, and the like. In general, a photoconductive substance is used to form an electric electrostatic latent image on a photoconductor by various optical means, and then the electrostatic latent image is visualized by using toner. After the transfer, the image is fixed by heating or pressure to obtain a copy image.
【０００３】静電潜像をトナーを用いて可視像化する方
法として、米国特許第２８７４０６３に記載されている
磁気ブラシ法、同第２６１８５５２に記載されているカ
スケード現像法及び同第２９０９２５８に記載されてい
る導電性磁性トナーを用いる方法など種々知られてい
る。As a method of visualizing an electrostatic latent image using toner, a magnetic brush method described in US Pat. No. 2,870,403, a cascade developing method described in US Pat. No. 2,618,552 and a description of US Pat. No. 2,909,258 are described. Various methods are known, such as a method using a known conductive magnetic toner.
【０００４】また現像方法としては、おもに、キャリア
と呼ばれる鉄粉やガラスビーズ等とトナーを混合したも
のを現像剤として用いる二成分現像方式と、トナー単独
で用いる一成分現像方式がある。Further, as a developing method, there are mainly a two-component developing method using a mixture of iron powder or glass beads called a carrier and a toner as a developer, and a one-component developing method using a toner alone.
【０００５】前者の二成分現像方式はトナー及びキャリ
アを混合撹拌して相互の摩擦帯電によりトナーを帯電さ
せる現像方式であるため、帯電性、搬送性は安定する。
しかしこの方法はトナーが逐次消費されるため、トナー
とキャリアの比を常に一定に維持する機能が必要であ
り、小型、軽量化が困難である。The former two-component developing method is a developing method in which the toner and the carrier are mixed and stirred and the toner is charged by mutual frictional charging, so that the charging property and the transporting property are stable.
However, in this method, since the toner is sequentially consumed, it is necessary to have a function of always keeping the ratio of the toner and the carrier constant, and it is difficult to reduce the size and weight.
【０００６】小型、軽量が可能である後者の一成分現像
方式には磁気力でトナーを搬送、保持する磁性一成分現
像方式が多種考案されている。As the latter one-component developing system which can be made compact and lightweight, various magnetic one-component developing systems in which toner is conveyed and held by magnetic force have been devised.
【０００７】周知のようにこれらの現像方式で用いられ
る磁性トナーにおいては、トナーの帯電量を制御するた
めに、バインダー樹脂や電荷制御剤、外添剤の組成検討
が広く行われている。As is well known, in the magnetic toner used in these developing systems, the composition of the binder resin, the charge control agent and the external additive is widely studied in order to control the charge amount of the toner.
【０００８】たとえば、特開昭５４−１４３６４７号公
報で提案されているようにトナー帯電量を増加させるた
めに樹脂に官能基を付与したり、電荷制御剤添加量を増
加させたり、あるいは特公昭５９ー１６４５６２号公
報、特開昭６３ー１３９３６７号公報では強い帯電性を
示す乾式シリカを外添する事によってトナー帯電量が上
昇する事が示されている。For example, as proposed in Japanese Patent Laid-Open No. 54-143647, a functional group is added to the resin in order to increase the toner charge amount, the charge control agent addition amount is increased, or In JP-A 59-164562 and JP-A 63-139367, it is shown that the toner charge amount is increased by externally adding dry silica having a strong charging property.
【０００９】[0009]
【発明が解決しようとする課題】しかしながらこれらの
方法は、いずれも比較的簡単にトナー帯電量を制御する
事が可能な方法であるが、磁性トナーの場合には磁性粉
の比抵抗が低いため磁性粉の含有量が増加するとトナー
の電気抵抗は急激に低下し、帯電量を増加させる事は困
難になるため、電荷制御剤の増量やシリカ添加量変更を
行うと環境安定性の悪化や個々のトナーにおける分散性
の悪化が発生するという問題点を有している。However, all of these methods can relatively easily control the toner charge amount, but in the case of a magnetic toner, the specific resistance of the magnetic powder is low. When the content of magnetic powder increases, the electric resistance of the toner sharply decreases, making it difficult to increase the charge amount.Therefore, increasing the amount of charge control agent or changing the amount of silica added may deteriorate environmental stability or However, there is a problem that the dispersibility of the toner is deteriorated.
【００１０】これは、電荷制御剤などは多くの官能基を
もつため、表面に水分を吸着しやすく特に高温高湿下に
おいて十分な帯電量が得られなかったり、電荷制御剤の
トナー中への分散やシリカのトナー表面への均一付着が
その量比が増加するにつれ困難になる事に起因してい
る。This is because the charge control agent and the like have many functional groups, so that water is likely to be adsorbed on the surface, and a sufficient charge amount cannot be obtained especially under high temperature and high humidity, and the charge control agent may be incorporated in the toner. This is because dispersion and uniform adhesion of silica to the toner surface become difficult as the amount ratio increases.
【００１１】本発明はこのような事態に対処すべくなさ
れたものであって、トナー表面に露出した磁性粉を磁性
トナー表面を改質する事によって減少させ、トナーの誘
電体損を低下させる事によって電荷制御剤などの添加量
を増加させることなくトナー帯電量制御を行う事を目的
とする。The present invention has been made to cope with such a situation, and reduces the magnetic powder exposed on the toner surface by modifying the surface of the magnetic toner to reduce the dielectric loss of the toner. The purpose is to control the toner charge amount without increasing the amount of charge control agent added.
【００１２】[0012]
【課題を解決するための手段】上記の目的を達成するた
め、本発明は、少なくともバインダー樹脂と磁性体から
構成される磁性トナーを表面改質させて、前記磁性トナ
ーの誘電体損が３．５×１０-3以下である事を特徴とす
るものである。In order to achieve the above-mentioned object, according to the present invention, a magnetic toner composed of at least a binder resin and a magnetic material is surface-modified so that the dielectric loss of the magnetic toner is 3. It is characterized by being 5 × 10 −3 or less.
【００１３】磁性トナーの誘電体損が３．５×１０-3以
下であれば、磁性トナー表面に露出する磁性体量が減少
し磁性トナーの表面抵抗値が増加する事により、表面か
らリークする電荷量が減少する事から磁性トナーの帯電
量が向上するのである。When the dielectric loss of the magnetic toner is 3.5 × 10 −3 or less, the amount of the magnetic substance exposed on the surface of the magnetic toner decreases and the surface resistance value of the magnetic toner increases, so that the surface leaks. Since the charge amount is reduced, the charge amount of the magnetic toner is improved.
【００１４】以下本発明の磁性トナーについて詳細に説
明する。本発明における磁性トナーは少なくともバイン
ダー樹脂と磁性体、必要に応じて電荷制御剤、離型剤、
流動化剤、着色剤、第２の外添物質から構成される。バ
インダー樹脂としては公知のものすべてが使用可能であ
るが、たとえばスチレン系樹脂、アクリル系樹脂、ポリ
エステル樹脂、エポキシ樹脂、ビニル系樹脂、テルペン
樹脂、フェノール樹脂、あるいはそれらの共重合体樹脂
等が用いられる。The magnetic toner of the present invention will be described in detail below. The magnetic toner in the present invention includes at least a binder resin and a magnetic material, and if necessary, a charge control agent, a release agent,
It is composed of a fluidizing agent, a coloring agent, and a second external additive. As the binder resin, all known ones can be used, but for example, a styrene resin, an acrylic resin, a polyester resin, an epoxy resin, a vinyl resin, a terpene resin, a phenol resin, or a copolymer resin thereof is used. To be
【００１５】磁性体としては、フェライト、マグネタイ
ト、ヘマタイトなどの鉄、マンガン、コバルト、ニッケ
ル、銅、亜鉛、マグネシウムなどの合金や化合物など強
磁性体として知られる物質が使用できる。これらの磁性
体を平均粒径約0.05〜5μｍ好ましくは0.1〜1μｍの微
粉末としてバインダー樹脂１００重量部あたり３０〜１
００重量部好ましくは４０〜９０重量部含有させればよ
い。As the magnetic material, materials known as ferromagnetic materials such as iron, manganese, cobalt, nickel, copper, zinc, magnesium and other alloys and compounds such as ferrite, magnetite and hematite can be used. These magnetic materials are fine powders having an average particle size of about 0.05 to 5 μm, preferably 0.1 to 1 μm, and 30 to 1 per 100 parts by weight of the binder resin.
00 parts by weight, preferably 40 to 90 parts by weight.
【００１６】さらに本発明で使用される磁性トナー中に
は必要に応じて各種染顔料などの電荷制御剤、ポリエチ
レン、ポリプロピレンなどの離型剤、シリカ、アルミ
ナ、ジルコニア、チタニアなどの各種金属酸化物、カー
ボンブラック等の着色剤が含有、あるいは外添されてい
てもよい。Further, in the magnetic toner used in the present invention, if necessary, a charge control agent such as various dyes and pigments, a release agent such as polyethylene and polypropylene, and various metal oxides such as silica, alumina, zirconia and titania. A colorant such as carbon black may be contained or externally added.
【００１７】誘電体損は、磁性トナーを100kg／cｍ2の
加圧下で12mmφのペレット状に成形し、ＬＣＲメーター
を用い周波数1kHzで測定した。The dielectric loss was measured by molding the magnetic toner into pellets of 12 mmφ under a pressure of 100 kg / cm 2 and using a LCR meter at a frequency of 1 kHz.
【００１８】また、トナー帯電量はブローオフ帯電量測
定装置によって測定した。The toner charge amount was measured by a blow-off charge amount measuring device.
【００１９】[0019]
【作用】前記のようにして作成された磁性トナーは、電
荷制御剤によらず帯電量制御が行える事から環境安定性
が向上し、また電荷制御剤の分散性悪化による帯電の不
安定を解決できるため、環境変動に対して性能変化がな
く、画像濃度が十分に高いものである。The magnetic toner produced as described above can improve the environmental stability because the charge amount can be controlled without using the charge control agent, and the instability of charging due to the deterioration of the dispersibility of the charge control agent can be solved. As a result, the performance does not change due to environmental changes, and the image density is sufficiently high.
【００２０】[0020]
【実施例】以下本発明の実施例について図面を参照しな
がら説明する。本発明はこれに限定されるものではな
い。Embodiments of the present invention will be described below with reference to the drawings. The present invention is not limited to this.
【００２１】図１は本発明の磁性トナーの構成を示して
いる。磁性トナーはバインダー樹脂１と磁性粉２、電荷
制御剤３、離型剤４、流動化剤５、着色剤６、第２の外
添物質７から構成される。電荷制御剤、離型剤、流動化
剤、着色剤、第２の外添物質は含有させる必要がなけれ
ば、含有させなくとも良い。FIG. 1 shows the structure of the magnetic toner of the present invention. The magnetic toner is composed of a binder resin 1, magnetic powder 2, a charge control agent 3, a release agent 4, a fluidizing agent 5, a coloring agent 6, and a second external additive material 7. The charge control agent, the release agent, the fluidizing agent, the colorant, and the second external additive substance may be omitted if they are not required.
【００２２】（実施例１）実施例１で使用されるトナー
a1の材料組成を（表１）に示した。(Example 1) Toner used in Example 1
The material composition of a1 is shown in (Table 1).
【００２３】[0023]
【表１】 [Table 1]
【００２４】（表１）に示した物質を混合後溶融混練
し、冷却後粉砕、分級して平均粒径１０μｍの磁性トナ
ー粉末を得た。この磁性トナーを３５０℃の熱気流中に
導入しトナー表面樹脂を溶融させ磁性体の露出を抑える
処理を行い磁性トナーa1を完成した。The substances shown in Table 1 were mixed, melt-kneaded, cooled, pulverized and classified to obtain a magnetic toner powder having an average particle diameter of 10 μm. The magnetic toner a1 was completed by introducing the magnetic toner into a hot air stream at 350 ° C. to melt the resin on the toner surface and suppress the exposure of the magnetic material.
【００２５】この磁性トナーの誘電体損を測定したとこ
ろ２．８×１０ー3であった。この磁性トナーの帯電量を
７℃１０％の低温低湿下、３３℃８０％の高温高湿下で
測定したところ、高帯電量が得られ、環境による影響は
少なかった。（表２）に各磁性トナーの誘電体損、帯電
量を示した。The dielectric loss of this magnetic toner was measured and found to be 2.8 × 10 −3 . When the charge amount of this magnetic toner was measured under a low temperature and low humidity condition of 7 ° C. and 10% and a high temperature and high humidity condition of 33 ° C. and 80%, a high charge amount was obtained and the influence of the environment was small. Table 2 shows the dielectric loss and charge amount of each magnetic toner.
【００２６】また、この磁性トナーを松下電器産業
（株）製レーザービームプリンタＦＰ−Ｌ３３０改造機
を使用して７℃１０％の低温低湿下、３３℃８０％の高
温高湿下で印字を行った。（表３）に各磁性トナーの画
像濃度を示す。The magnetic toner was printed using a modified laser beam printer FP-L330 manufactured by Matsushita Electric Industrial Co., Ltd. at a low temperature and low humidity of 7 ° C. and 10% and a high temperature and high humidity of 33 ° C. and 80%. It was Table 3 shows the image density of each magnetic toner.
【００２７】[0027]
【表２】 [Table 2]
【００２８】[0028]
【表３】 [Table 3]
【００２９】（実施例２）実施例２で使用されるトナー
a2の材料組成を（表４）に示した。(Example 2) Toner used in Example 2
The material composition of a2 is shown in (Table 4).
【００３０】[0030]
【表４】 [Table 4]
【００３１】（表４）に示した物質を混合後溶融混練
し、冷却後粉砕、分級して平均粒径１０μｍの磁性トナ
ー粉末を得た。この磁性トナーをヘンシュルミキサー
（三井三池化工機 ＦＭ−２０Ｂ）に１ｋｇ投入し２０
００r.p.m.で３０分間撹拌しトナー表面に衝撃力を連続
して作用させた。The materials shown in Table 4 were mixed, melt-kneaded, cooled, pulverized and classified to obtain a magnetic toner powder having an average particle size of 10 μm. 1 kg of this magnetic toner was put into a Henshur mixer (Mitsui Miike Kakoki FM-20B), and 20
The toner surface was stirred at 00 rpm for 30 minutes, and the impact force was continuously applied to the toner surface.
【００３２】この磁性トナーの誘電体損を測定したとこ
ろ３．３×１０ー3であった。 （比較例１）比較例１で使用されるトナーa3の材料組成
を（表５）に示した。The dielectric loss of this magnetic toner was measured and found to be 3.3 × 10 −3 . (Comparative Example 1) The material composition of the toner a3 used in Comparative Example 1 is shown in (Table 5).
【００３３】[0033]
【表５】 [Table 5]
【００３４】（表５）に示した物質を混合後溶融混練
し、冷却後粉砕、分級して平均粒径１０μｍの磁性トナ
ー粉末を得た。The substances shown in Table 5 were mixed, melt-kneaded, cooled, pulverized and classified to obtain a magnetic toner powder having an average particle size of 10 μm.
【００３５】この磁性トナーの誘電体損を測定したとこ
ろ４．７×１０ー3であった。表面改質を行なったものに
比べて帯電量が低く特に高温高湿下で顕著であった。The dielectric loss of this magnetic toner was measured and found to be 4.7 × 10 −3 . The amount of charge was lower than that of the surface-modified product, which was remarkable especially under high temperature and high humidity.
【００３６】（比較例２）比較例２で使用されるトナー
a4の材料組成を（表６）に示した。Comparative Example 2 Toner used in Comparative Example 2
The material composition of a4 is shown in (Table 6).
【００３７】[0037]
【表６】 [Table 6]
【００３８】（表６）に示した物質を（比較例１）と同
様の方法でトナー化して平均粒径１０μｍの磁性トナー
粉末を得た。The substances shown in (Table 6) were made into toner by the same method as in (Comparative Example 1) to obtain magnetic toner powder having an average particle size of 10 μm.
【００３９】この磁性トナーの誘電体損は４．９×１０
ー3であった。表面改質を行なったものに比べて低温低湿
下での帯電量は大差なかったが高温高湿下での帯電量低
下が顕著であった。The dielectric loss of this magnetic toner is 4.9 × 10.
It was -3 . There was no great difference in the charge amount under low temperature and low humidity as compared with the surface-modified one, but the decrease in charge amount under high temperature and high humidity was remarkable.
【００４０】[0040]
【発明の効果】本発明は、上記の構成により、以下の効
果を奏する。磁性トナーの表面を改質する事により誘電
体損を３．５×１０ー3以下に抑えることによって、電荷
制御剤増量によらず帯電量制御が可能になり、高温高
湿、低温低湿環境下でのトナー帯電量安定化、画像濃度
安定化を達成することができる。The present invention has the following effects due to the above configuration. By suppressing the dielectric loss to 3.5 × 10-3 or less by modifying the surface of the magnetic toner, it becomes possible to control the charge amount regardless of the increase in the amount of the charge control agent. It is possible to stabilize the toner charge amount and the image density.
【図１】磁性トナーの組成模式図FIG. 1 is a schematic diagram of the composition of magnetic toner.
１ バインダー樹脂 ２ 磁性粉 ３ 電荷制御剤 ４ 離型剤 ５ 流動化剤 ６ 着色剤 ７ 第２の外添物質 1 Binder Resin 2 Magnetic Powder 3 Charge Control Agent 4 Release Agent 5 Fluidizer 6 Colorant 7 Second External Additive
Claims (2)
成される磁性トナーであって、前記バインダー樹脂の軟
化点以上の温度を持つ熱風気流中に前記磁性トナーを分
散させる行程を用いて熱処理により前記磁性トナーを表
面改質させて、前記磁性トナーの誘電体損が３．５×１
０-3以下である事を特徴とする磁性トナー。1. A magnetic toner comprising at least a binder resin and a magnetic material, wherein the magnetic toner is heat-treated using a process of dispersing the magnetic toner in a hot air stream having a temperature equal to or higher than the softening point of the binder resin. The surface loss of the toner is modified so that the dielectric loss of the magnetic toner is 3.5 × 1.
A magnetic toner characterized in that it is 0 -3 or less.
成される磁性トナーであって、回転または振動する撹拌
衝撃部材が発生する連続衝撃力を前記磁性トナーに与え
る手段を用いて前記磁性トナーを表面改質させて、前記
磁性トナーの誘電体損が３．５×１０-3以下である事を
特徴とする磁性トナー。2. A magnetic toner comprising at least a binder resin and a magnetic material, the surface of the magnetic toner being modified by means for applying a continuous impact force generated by a stirring impact member that rotates or vibrates to the magnetic toner. A magnetic toner characterized in that the dielectric loss of the magnetic toner is 3.5 × 10 −3 or less.
Priority Applications (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP04202191A JP3094676B2 (en) | 1992-07-29 | 1992-07-29 | Magnetic toner |
| EP19930112029 EP0581257B1 (en) | 1992-07-29 | 1993-07-28 | Electrophotographic magnetic toner for development an image and a method of producing the same |
| DE1993622138 DE69322138T2 (en) | 1992-07-29 | 1993-07-28 | Electrophotographic magnetic toner for developing an image and method for producing the same |
| US08/653,014 US5985506A (en) | 1992-07-29 | 1996-05-24 | Reversal electrophotographic developing method employing recyclable magnetic toner |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP04202191A JP3094676B2 (en) | 1992-07-29 | 1992-07-29 | Magnetic toner |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0651556A true JPH0651556A (en) | 1994-02-25 |
| JP3094676B2 JP3094676B2 (en) | 2000-10-03 |
Family
ID=16453475
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP04202191A Expired - Fee Related JP3094676B2 (en) | 1992-07-29 | 1992-07-29 | Magnetic toner |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3094676B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6670087B2 (en) | 2000-11-07 | 2003-12-30 | Canon Kabushiki Kaisha | Toner, image-forming apparatus, process cartridge and image forming method |
| JP2009069840A (en) * | 2008-10-23 | 2009-04-02 | Ricoh Co Ltd | Color developing method, developing apparatus and developing toner for electrostatic latent image |
| US8765346B2 (en) | 2012-04-16 | 2014-07-01 | Kyocera Document Solutions Inc. | Magnetic single-component developer |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1241530B1 (en) | 2001-03-15 | 2006-03-22 | Canon Kabushiki Kaisha | Magnetic toner and process cartridge |
| CN100472335C (en) * | 2002-08-23 | 2009-03-25 | 株式会社理光 | Toner and its mfg. method, developer, imaging device and toner fixing method |
-
1992
- 1992-07-29 JP JP04202191A patent/JP3094676B2/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6670087B2 (en) | 2000-11-07 | 2003-12-30 | Canon Kabushiki Kaisha | Toner, image-forming apparatus, process cartridge and image forming method |
| JP2009069840A (en) * | 2008-10-23 | 2009-04-02 | Ricoh Co Ltd | Color developing method, developing apparatus and developing toner for electrostatic latent image |
| US8765346B2 (en) | 2012-04-16 | 2014-07-01 | Kyocera Document Solutions Inc. | Magnetic single-component developer |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3094676B2 (en) | 2000-10-03 |
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