JPH07181749A - Liquid developer - Google Patents

Liquid developer

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Publication number
JPH07181749A
JPH07181749A JP5346504A JP34650493A JPH07181749A JP H07181749 A JPH07181749 A JP H07181749A JP 5346504 A JP5346504 A JP 5346504A JP 34650493 A JP34650493 A JP 34650493A JP H07181749 A JPH07181749 A JP H07181749A
Authority
JP
Japan
Prior art keywords
magnetic substance
magnetic
org
magnetic material
particles
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
Application number
JP5346504A
Other languages
Japanese (ja)
Inventor
Yoshikazu Shudo
美和 首藤
Koji Ujiie
孝二 氏家
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ricoh Co Ltd
Original Assignee
Ricoh Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Ricoh Co Ltd filed Critical Ricoh Co Ltd
Priority to JP5346504A priority Critical patent/JPH07181749A/en
Publication of JPH07181749A publication Critical patent/JPH07181749A/en
Pending legal-status Critical Current

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  • Liquid Developers In Electrophotography (AREA)

Abstract

PURPOSE:To ensure very satisfactory dispersibility of particles of a magnetic substance in a liq. and superor fixability by using an org. magnetic material as the magnetic substance. CONSTITUTION:In the liq. developer based on at least particles contg. a magnetic substance and a carrier liq., an org. magnetic material is used as the magnetic substance. This org. magnetic material is, e.g. a condensed polycyclic polynuclear aro. resin magnetic substance, an org. magnetic substance made of an org. metallic complex such as poly-bis-2,6- pyridinediylmethylidenenitrilohexamethylenenitrilomethylidene iron sulfate or an org. magnetic substance made of a specified ferrocen polymer. Since the magnetic substance has a low specific gravity and high compatibility with other org. material to be combined, satisfactory uniform dispersibility of the magnetic substance in the particles is ensured. Since the specific gravity of the magnetic substance is low, the dispersibility of the particles contg. the magnetic substance in the liq. developer is considerably improved and a clear image is obtd. Since the magnetic substance has self-fixability, satisfactory fixability is ensured.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は、磁界印加電子写真現像
法を用いる湿式現像プロセスにおける液体現像剤に関す
る。
FIELD OF THE INVENTION The present invention relates to a liquid developer in a wet development process using a magnetic field application electrophotographic development method.

【0002】[0002]

【従来の技術】電子写真法あるいは静電記録法により画
像を得るには、電子写真感光体や静電記録紙等に常法で
正又は負に帯電している静電潜像を形成させ、正又は負
に帯電している液体現像剤中のトナー粒子をこれに付着
させて可視像化する。この場合、静電潜像を乾式現像剤
で可視像化することも行なわれているが、解像力が高い
高品質の画像を得る方法としては湿式現像法が有利であ
る。
2. Description of the Related Art To obtain an image by an electrophotographic method or an electrostatic recording method, an electrostatic latent image which is positively or negatively charged is formed on an electrophotographic photosensitive member or electrostatic recording paper by a conventional method. Toner particles in the liquid developer that are positively or negatively charged are attached to the toner particles to form a visible image. In this case, the electrostatic latent image is visualized with a dry developer, but a wet developing method is advantageous as a method for obtaining a high-quality image having high resolution.

【0003】この液体現像剤を用いた湿式複写プロセス
及び形成画像には、微粒子トナーによる現像のため高
解像度の画像が得られる、画像の定着が容易である、
階調再現性が優れ写真の再現性が良い、現像、定着
部の設計がコンパクトにできるなどという特徴があり、
これらのメリットのため広く市場に普及している。基本
的に湿式プロセスにおいては、荷電トナー粒子が潜像電
荷の電界中で静電的に潜像に引きつけられて表面に付着
し現像が終了するが、トナー粒子の移動の促進と効率化
を図り、現像液の濃度調整を行なう等の理由で潜像付近
に現像電極を設けたり、電極ローラにより現像液を潜像
担体へ供給する等の方法が採用されている(例えば、米
国特許第3,429,088号、米国特許第3,50
0,793号各明細書、特公昭44−23792号公報
等)。
In the wet copying process and the formed image using this liquid developer, a high-resolution image can be obtained due to the development with fine particle toner, and the fixing of the image is easy.
Features such as excellent gradation reproducibility, good photo reproducibility, and compact design of development and fixing parts.
Due to these merits, it is widely used in the market. Basically, in the wet process, charged toner particles are electrostatically attracted to the latent image in the electric field of the latent image charge and adhere to the surface to complete the development, but the movement of the toner particles is promoted and the efficiency is improved. In order to adjust the concentration of the developing solution, a developing electrode is provided in the vicinity of the latent image, or the developing solution is supplied to the latent image carrier by an electrode roller (for example, US Pat. 429,088, U.S. Pat. No. 3,50.
No. 0,793 each specification, Japanese Patent Publication No. 44-23792, etc.).

【0004】これに対し、現像液中に磁性トナーを分散
させた現像液を用い、この現像液中のトナーに磁界を作
用させて現像液中のトナー濃度分布を規制する磁界印加
現像法が提案されている(特公昭49−46263号、
特公昭59−99号各公報)。また、湿式現像にて現像
したトナー像を転写用紙に転写する手法として、磁界転
写法も提案されている。
On the other hand, a magnetic field application developing method is proposed in which a developer in which a magnetic toner is dispersed is used and a magnetic field is applied to the toner in the developer to regulate the toner concentration distribution in the developer. (Japanese Patent Publication No. 49-46263,
Japanese Patent Publication No. 59-99). A magnetic field transfer method has also been proposed as a method for transferring a toner image developed by wet development to a transfer sheet.

【0005】[0005]

【発明が解決しようとする課題】ただ、上記の磁性トナ
ーを分散させた現像液では、湿式トナーに磁性を持たせ
るために、いずれも磁性金属、金属合金、並びに金属酸
化物、γ−フェライト等が使用されている。ところが、
無機の磁性体の場合、比重は一般に3以上であり、特に
磁性トナーとして用いられる無機磁性体の比重は5〜6
である。これらの磁性体が少なくとも20重量%、多く
は80重量%程度の割合で混入され、磁性トナーとなる
ので、その比重は少なくとも1.8程度である。従っ
て、このトナーは現像液の撹拌分散を中止すると、直ち
に沈降するという欠点がある。また、磁性粉末がマグネ
ットに直接接触すると数珠つなぎとなるので、個々の粉
末の分離が悪くなり、静電荷力によっても、マグネット
から離れ難くなり、現像スピードが低下するし、更に磁
性粉体のみの可視画像は、定着性が全くないため、別途
に定着工程を必要とし、その結果現像方式及び現像装置
自体が複雑化するという欠点もある。このため、磁性粉
体に樹脂を被膜したトナーを用いた現像剤が提案されて
いるが、製造過程が煩雑になり、また、必ずしもよい結
果が得られてはいない。
However, in the above-mentioned developer in which the magnetic toner is dispersed, in order to impart magnetism to the wet toner, all of them are magnetic metals, metal alloys, metal oxides, γ-ferrite, etc. Is used. However,
In the case of an inorganic magnetic material, the specific gravity is generally 3 or more, and particularly the inorganic magnetic material used as a magnetic toner has a specific gravity of 5 to 6
Is. These magnetic substances are mixed in at least 20% by weight, and most of them are about 80% by weight to form a magnetic toner, so that their specific gravity is at least about 1.8. Therefore, this toner has a drawback that it immediately settles when the stirring and dispersing of the developer is stopped. In addition, when the magnetic powder directly contacts the magnet, it becomes a string of beads, so the separation of the individual powders deteriorates, it becomes difficult to separate from the magnet even by the electrostatic charge force, and the developing speed decreases. Since a visible image has no fixing property, a separate fixing process is required, and as a result, the developing system and the developing device itself are complicated. For this reason, a developer using a toner in which a magnetic powder is coated with a resin has been proposed, but the manufacturing process is complicated, and good results are not always obtained.

【0006】従って、本発明は上記従来技術の実情に鑑
みてなされたものであって、液中での磁性体粒子の分散
性が極めて良好でしかも定着性にも優れている液体現像
剤を提供することを、その目的とする。
Therefore, the present invention has been made in view of the above-mentioned conventional state of the art, and provides a liquid developer in which the dispersibility of magnetic particles in a liquid is extremely good and the fixing property is also excellent. The purpose is to do.

【0007】[0007]

【課題を解決するための手段】本発明によれば、少なく
とも磁性体を含む粒体と担体液とを主成分とする液体現
像剤において、該磁性体として有機磁性材料を用いたこ
とを特徴とする液体現像剤が提供される。
According to the present invention, an organic magnetic material is used as the magnetic material in a liquid developer containing, as main components, a granular material containing at least a magnetic material and a carrier liquid. A liquid developer is provided.

【0008】特に本発明によれば、前記有機磁性材料が
透明性の高いものであるカラー現像に適した液体現像剤
が提供され、更に前記磁性体を含む粒体の比重が1.8
以下である液体現像剤が提供される。
In particular, according to the present invention, there is provided a liquid developer suitable for color development in which the organic magnetic material is highly transparent, and the specific gravity of the particles containing the magnetic material is 1.8.
The following liquid developer is provided.

【0009】近年、ある種の有機材料が磁性を持つこと
が発見され、縮合多環芳香族系樹脂、ポリ−ビス−2,
6−ピリジンジイルメチリデン・硫酸鉄、フェロセンポ
リマー類、ポリフィナート系金属錯体その他の有機磁性
体が、例えば、一成分系乾式カラートナー用材料として
提案されている(特開平3−33865号、特開平3−
33866号、特開平3−140966号特開平3−1
40967号、特開平3−289666号、特開平4−
179966号、特開平4−192306号、特開平5
−134451号、特開平5−267042号各公
報)。これらの有機磁性体は、トナー粒子内に均一に配
合され、密度も低く、現像器内での撹拌性が良好である
とか、また、鮮明に着色材料の色を出せるカラー画像が
得られる等の利点を有する。ただ、乾式トナー用磁性体
として有用であるからといって、湿式トナー用磁性体と
して有効であるか否かは、液体中での分散性や可視画像
の定着性等の問題があるので、予測し得ない。
Recently, it was discovered that certain organic materials have magnetism, and condensed polycyclic aromatic resins, poly-bis-2,
Organic magnetic materials such as 6-pyridinediyl methylidene / iron sulfate, ferrocene polymers, polyfinate metal complexes and other organic magnetic materials have been proposed, for example, as materials for one-component dry color toners (JP-A-3-33865, JP-A-3-33865). 3-
33866, JP-A-3-140966, JP-A 3-1
40967, JP-A-3-289666, JP-A-4-
179966, JP-A-4-192306, JP-A-5
-134451, JP-A-5-267042). These organic magnetic materials are uniformly blended in the toner particles, have a low density, have good agitation property in the developing device, and can obtain a color image that clearly shows the color of the coloring material. Have advantages. However, since it is useful as a magnetic material for dry toner, whether it is effective as a magnetic material for wet toner has some problems such as dispersibility in liquid and fixability of visible image. I can't.

【0010】しかし、本発明者らの研究の結果、上述の
ような有機磁性体は、液体現像剤用としても極めて有用
であることが判明した。即ち、上記の有機磁性体は無機
磁性材料に比べると比重がずっと小さく(一般に0.7
〜4.3)、特にハロゲン原子を含まない場合は0.7
〜1.8となる。しかも、他の有機材料との相溶性が高
く、他の有機材料と複合した場合の分散性(均一性)が
良い。また、特にある種の有機磁性材料は透明性が高
い。従って、磁性体を含む粒子からなる液体現像剤にお
いて、有機磁性体を用いると、粒子の比重が軽いため、
液中での粒子の分散性が飛躍的に良くなる。また、電荷
制御剤、着色剤等との相溶性も高く、単体で自己定着性
もあるため、バインダー樹脂が必がしも必要でなくな
る。更に、粒子内でのトナー構成材料の分散性が良くな
るため、粒子表面での静電特性が均一になる。
However, as a result of the research conducted by the present inventors, it has been found that the above-mentioned organic magnetic material is extremely useful as a liquid developer. That is, the specific gravity of the above organic magnetic material is much smaller than that of the inorganic magnetic material (generally, 0.7).
~ 4.3), especially 0.7 when not containing a halogen atom
It becomes ~ 1.8. In addition, it has high compatibility with other organic materials and good dispersibility (uniformity) when combined with other organic materials. Also, in particular, some organic magnetic materials have high transparency. Therefore, when the organic magnetic material is used in the liquid developer composed of particles containing a magnetic material, the specific gravity of the particles is small,
The dispersibility of the particles in the liquid is dramatically improved. In addition, the compatibility with the charge control agent, the colorant and the like is high, and the self-fixing property of the simple substance is eliminated, so that the binder resin is not always necessary. Furthermore, since the dispersibility of the toner constituent material within the particles is improved, the electrostatic characteristics on the surface of the particles become uniform.

【0011】本発明で使用される有機磁性材料として
は、例えば、縮合多環多核芳香族系樹脂磁性体(特開
平3−33865号、特開平4−179966号公報等
に記載)、ポリ−ビス−2,6−ピリジンジイルメチ
リデンニトリロヘキサメチレンニトリロメチリデン・硫
酸鉄等の有機金属錯体からなる有機磁性体(特開平3−
33865号公報等に記載)、ポルフィナート系共重
合体高分子金属錯体からなる有機磁性体(特開平3−2
89666号公報)特定のフェロンポリマーからなる
有機磁性体(特開平5−134451号、特開平5−2
67042号各公報に記載)等が挙げられる。これらの
有機磁性体について、以下詳細に説明する。
Examples of the organic magnetic material used in the present invention include condensed polycyclic polynuclear aromatic resin magnetic materials (described in JP-A-3-33865 and JP-A-4-179966) and poly-bis. Organic magnetic substance composed of organic metal complex such as -2,6-pyridinediylmethylidene nitrilohexamethylene nitrilomethylidene-iron sulfate
33865, etc.), an organic magnetic material comprising a porphinate-based copolymer polymer metal complex (Japanese Patent Laid-Open No. 3-2).
89666) Organic magnetic material composed of specific feron polymer (Japanese Patent Laid-Open Nos. 5-134451 and 5-2)
No. 67042). These organic magnetic materials will be described in detail below.

【0012】縮合多環多核芳香族系樹脂磁性体 COPNA樹脂と呼ばれているものであって、具体例と
しては、次のものが挙げられる。ピレン−ベンズアルデ
ヒド樹脂、ピレン−テレフタルアルデヒド樹脂、ピレン
−イソフタルアルデヒド樹脂、フェノール−べンズアル
デヒド樹脂、p−ヒドロキシベンズアルデヒド樹脂、ア
ントラセン−ベンズアルデヒド樹脂、アントラセン−テ
レフタルアルデヒド樹脂、アントラセン−イソフタルア
ルデヒド樹脂等。
Condensed polycyclic polynuclear aromatic resin magnetic material This is called a COPNA resin, and specific examples thereof include the following. Pyrene-benzaldehyde resin, pyrene-terephthalaldehyde resin, pyrene-isophthalaldehyde resin, phenol-benzaldehyde resin, p-hydroxybenzaldehyde resin, anthracene-benzaldehyde resin, anthracene-terephthalaldehyde resin, anthracene-isophthalaldehyde resin and the like.

【0013】ポリ−ビス−2,6−ピリジンジイルメ
チリデンニトリロヘキサメチレンニトリロメチリデン・
硫酸鉄等の有機金属錯体からなる磁性体〔F.Lion
s and K. V. Martin:J.Am.S
oc.,79,2733(1957)参照〕
Poly-bis-2,6-pyridinediyl methylidene nitrilohexamethylene nitrilomethylidene
Magnetic substance composed of an organic metal complex such as iron sulfate [F. Lion
s and K.S. V. Martin: J. Am. S
oc. , 79 , 2733 (1957)].

【0014】ポルフィナート系共重合体高分子金属錯
体からなる有機磁性体 この高分子金属錯体は、ポリマー主鎖に、エステル基を
介して、d軌道に電子1個をもつ金属を含有するポルフ
ィン類と、d軌道に電子9個をもつ金属を含有するポリ
フィリン類とを導入したものである。この高分子金属錯
体の具体例としては、例えば5−(4−アクリロイロキ
シフェニル)−10,15,20−トリフェニルポルフ
ィナート銅(II)/5−(4−アクリロイロキシフェニ
ル)−10,15,20−トリフェニルポルフィナート
バナジル(II)共重合体、5−(4−アクリロイロキシ
フェニル)−10,15,20−トリフェニルポルフィ
ナート銀(II)/5−(4−アクリロイロキシフェニ
ル)−10,15,20−トリフェニルポルフィナート
バナジル(II)共重合体などが挙げられる。
Porphynate Copolymer Organic Magnetic Material Consisting of Polymer Metal Complex This polymer metal complex is composed of porphines containing a metal having one electron in the d orbital in the polymer main chain through an ester group. , Porphyrins containing a metal having 9 electrons in the d orbital. Specific examples of the polymer metal complex include, for example, 5- (4-acryloyloxyphenyl) -10,15,20-triphenylporphinate copper (II) / 5- (4-acryloyloxyphenyl) -10. , 15,20-Triphenylporphinato vanadyl (II) copolymer, 5- (4-acryloyloxyphenyl) -10,15,20-triphenylporphinato silver (II) / 5- (4-acryloyl) Roxyphenyl) -10,15,20-triphenylporphinato vanadyl (II) copolymer and the like.

【0015】フェロセンポリマーからなる有機磁性体 本発明で使用されるフェロセンポリマーは、下記一般式
〔I〕
Organic Magnetic Material Consisting of Ferrocene Polymer The ferrocene polymer used in the present invention has the following general formula [I]:

【化1】 (式中、Rはアルキル基、アリール基、アルケニル基、
アルアルキル基又はアルアルケニル基を表わし、またn
は重合度を表わす。)で表わされるフェロセンポリマー
の主鎖を酸化剤により脱水素したものである。フェロセ
ンポリマーが有機磁性体として有用であることは知られ
ているが、本発明で使用されるフェロセンポリマーは、
ポリマー主鎖が酸化剤によって脱水素処理を受けたもの
であって、特に強磁性が賦与されたものである。このフ
ェロセンポリマーの具体例としては、フェロセン/ベン
ズアルデヒド縮合ポリマー脱水素化合物、フェロセン/
ケイ皮アルデヒド縮合ポリマー脱水素化合物、フェロセ
ン/クロトンアルデヒド縮合ポリマー脱水素化合物、フ
ェロセン/n−ノニルアルデヒド縮合ポリマー脱水素化
合物などが挙げられる。
[Chemical 1] (In the formula, R is an alkyl group, an aryl group, an alkenyl group,
Represents an aralkyl group or an alkenyl group, and n
Represents the degree of polymerization. The main chain of the ferrocene polymer represented by (4) is dehydrogenated with an oxidizing agent. Although it is known that the ferrocene polymer is useful as an organic magnetic substance, the ferrocene polymer used in the present invention is
The polymer main chain has been subjected to dehydrogenation treatment with an oxidizing agent, and is particularly imparted with ferromagnetism. Specific examples of the ferrocene polymer include ferrocene / benzaldehyde condensation polymer dehydrogenation compound, ferrocene /
Examples thereof include a cinnamic aldehyde condensation polymer dehydrogenation compound, a ferrocene / crotonaldehyde condensation polymer dehydrogenation compound, and a ferrocene / n-nonylaldehyde condensation polymer dehydrogenation compound.

【0016】また、本発明においては、フェロセンポリ
マーとして下記一般式〔II〕で表わされる構造の縮合重
合物が好ましく用いられる。
In the present invention, a condensation polymer having a structure represented by the following general formula [II] is preferably used as the ferrocene polymer.

【化2】 (式中、R1及びR2はそれぞれ水素原子又はアルキル基
を表わし、またmは重合度で1以上の整数を表わす。) 上記一般式〔II〕で示されるフェロセンポリマー構造を
有する有機磁性体の具体例としては、表1に示す構造単
位のものが挙げられる。
[Chemical 2] (In the formula, R 1 and R 2 each represent a hydrogen atom or an alkyl group, and m represents an integer of 1 or more in terms of polymerization degree.) Organic magnetic substance having a ferrocene polymer structure represented by the above general formula [II] Specific examples include those of the structural units shown in Table 1.

【0017】[0017]

【表1】 [Table 1]

【0018】なお、以上の有機磁性体の中でも、特にピ
レン−ベンズアルデヒド樹脂、ピレン−テレフタルアル
デヒド樹脂、ピレン−イソフタルアルデヒド樹脂、フェ
ノール−ベンズアルデヒド樹脂、p−ヒドロキシベンズ
アルデヒド樹脂、アントラセン−ベンズアルデヒド樹
脂、アントラセン−テレフタルアルデヒド樹脂、アント
ラセンイソフタルアルデヒド樹脂等の縮合多環芳香族系
樹脂は白色であり、これらの透明性の高い有機磁性材料
を用いた場合には、着色剤を添加することでカラー用の
液体現像剤を提供することができる。
Among the above organic magnetic materials, in particular, pyrene-benzaldehyde resin, pyrene-terephthalaldehyde resin, pyrene-isophthalaldehyde resin, phenol-benzaldehyde resin, p-hydroxybenzaldehyde resin, anthracene-benzaldehyde resin, anthracene-terephthalate resin. Fused polycyclic aromatic resins such as aldehyde resins and anthracene isophthalaldehyde resins are white, and when these highly transparent organic magnetic materials are used, a colorant can be added to add a liquid developer for color. Can be provided.

【0019】本発明において、有機磁性材料が有色の場
合には、着色剤等は必ずしも必要ではなく、また、ポリ
マーである場合には、バインダー樹脂が必ずしも必要で
はない。但し、着色性、定着性等を高める場合には、こ
れらを添加してもよい。この場合、着色剤、バインダー
樹脂、更に電荷制御剤、分散媒としては、従来より利用
されているものがそのまま利用ではる。
In the present invention, when the organic magnetic material is colored, the coloring agent or the like is not always necessary, and when it is a polymer, the binder resin is not always necessary. However, these may be added in the case of improving the coloring property, the fixing property and the like. In this case, as the colorant, the binder resin, the charge control agent, and the dispersion medium, those conventionally used can be used as they are.

【0020】[0020]

【実施例】次に、本発明を実施例により更に詳細に説明
するが、本発明はこれらに限定されるものではない。な
お、以下において示す部はいずれも重量基準である。
The present invention will now be described in more detail by way of examples, which should not be construed as limiting the invention. All parts shown below are based on weight.

【0021】実施例1 スチレン/n−ブチルメタクリレート共重合体 100部 フエロセン/ケイ皮アルデヒド縮合ポリマー磁性体 50部 上記組成の混合物をヘンシェルミキサーで充分撹拌混合
した後、ロールミルにて130〜140℃で30分間加
熱溶融し、これを室温まで冷却した。この混練物を粉
砕、分級し、1〜10μmの粒度の粉体を分取した。こ
の磁性粉体の比重は1.1であった。
Example 1 Styrene / n-butyl methacrylate copolymer 100 parts Ferrocene / cinnamic aldehyde condensation polymer magnetic material 50 parts The mixture having the above composition was sufficiently stirred and mixed by a Henschel mixer, and then at 130-140 ° C. by a roll mill. It was melted by heating for 30 minutes and cooled to room temperature. This kneaded product was crushed and classified to collect powder having a particle size of 1 to 10 μm. The specific gravity of this magnetic powder was 1.1.

【0022】この磁性粉体を、 磁性粉体 100部 カーボンブラック 5部 ナフテン酸ニッケル 0.01部 アイソパーH 100部 の割合でボールミル中で24時間分散して濃縮トナーと
し、その20gを1リットルのアイソパーHに分散させ
て、平均粒径3.5μmの本発明の現像剤を得た。
This magnetic powder was dispersed in a ball mill for 24 hours at a ratio of 100 parts of magnetic powder, 5 parts of carbon black, 0.01 part of nickel naphthenate and 100 parts of Isopar H to obtain a concentrated toner, 20 g of which was prepared as 1 liter. By dispersing in Isopar H, a developer of the present invention having an average particle size of 3.5 μm was obtained.

【0023】次に、この現像剤を、表面磁力700ガウ
スの8極マグネットを有するマグネットを内蔵したスリ
ーブ表面に、約500μmの液膜となるように保持し、
その液面にリコー社製BS−220機で静電潜像を形成
したZnO感光紙からなる静電潜像保持体を、紙送り速
度80mm/秒で接触させたところ、鮮明な画像が得ら
れた。
Next, this developer is held on the surface of a sleeve containing a magnet having an 8-pole magnet having a surface magnetic force of 700 gauss so as to form a liquid film of about 500 μm,
When an electrostatic latent image carrier made of ZnO photosensitive paper on which the electrostatic latent image was formed on the liquid surface by a Ricoh BS-220 machine was contacted at a paper feed speed of 80 mm / sec, a clear image was obtained. It was

【0024】実施例2 よりなる混合物をボールミルで60時間分散して濃縮ト
ナーとし、その20gをそれぞれ1リットルのアイソパ
ーHに分散させて、青色現像剤を得た。
Example 2 The mixture was dispersed in a ball mill for 60 hours to obtain a concentrated toner, and 20 g of each was dispersed in 1 liter of Isopar H to obtain a blue developer.

【0025】同様の方法で、赤、黄、青の現像液を作製
し、実施例1と同様の方法により4色の画像を重ね転写
してフルカラー複写を行なったところ、鮮明な画像が得
られた。
Red, yellow, and blue developers were prepared in the same manner, and four-color images were transferred in the same manner as in Example 1 to perform full-color copying. A clear image was obtained. It was

【0026】[0026]

【発明の効果】請求項1の液体現像剤は、磁性体として
有機磁性体を用いたことから、次のような卓越した効果
を奏する。 (イ)磁性体の比重が小さく、しかも複合される他の有機
材料との相溶性が高いので、磁性体を含む粒体内での均
一分散性が良好である。 (ロ)磁性体の比重が小さいので、液体現像剤における磁
性体を含む粒体の分散性が飛躍的に向上し、その結果、
本現像剤によると鮮明な画像が得られる。 (ハ)磁性体単体が自己定着性を有するので、定着性が良
好である。
The liquid developer according to the first aspect has the following excellent effects because the organic magnetic material is used as the magnetic material. (A) Since the specific gravity of the magnetic material is small and the compatibility with other organic materials to be composited is high, the uniform dispersibility in the particles containing the magnetic material is good. (B) Since the specific gravity of the magnetic material is small, the dispersibility of the particles containing the magnetic material in the liquid developer is dramatically improved, and as a result,
With this developer, a clear image can be obtained. (C) Since the magnetic substance alone has self-fixing property, the fixing property is good.

【0027】請求項2の液体現像剤は、前記有機磁性材
料が透明性の高いものであることから、本現像剤による
と、鮮明に着色材料の色を出せるカラー画像が得られ
る。
In the liquid developer according to the second aspect, since the organic magnetic material has high transparency, the present developer can provide a color image in which the color of the coloring material can be clearly produced.

【0028】請求項3の液体現像剤は、前記磁性体を含
む粒体の比重が1.8以下であることから、液体現像剤
における磁性体を含む粒体の分散性が更に向上するの
で、本現像剤によるとより鮮明な画像が得られる。
In the liquid developer of claim 3, since the specific gravity of the particles containing the magnetic material is 1.8 or less, the dispersibility of the particles containing the magnetic material in the liquid developer is further improved. With this developer, a clearer image can be obtained.

Claims (3)

【特許請求の範囲】[Claims] 【請求項1】 少なくとも磁性体を含む粒体と担体液と
を主成分とする液体現像剤において、該磁性体として有
機磁性材料を用いたことを特徴とする液体現像剤。
1. A liquid developer containing, as a main component, a granule containing at least a magnetic material and a carrier liquid, wherein an organic magnetic material is used as the magnetic material.
【請求項2】 前記有機磁性材料が透明性の高いもので
ある特にカラー現像に適した請求項1に記載の液体現像
剤。
2. The liquid developer according to claim 1, wherein the organic magnetic material has high transparency and is particularly suitable for color development.
【請求項3】 前記磁性体を含む粒体の比重が1.8以
下である請求項1又は2に記載の液体現像剤。
3. The liquid developer according to claim 1, wherein the specific gravity of the particles containing the magnetic material is 1.8 or less.
JP5346504A 1993-12-22 1993-12-22 Liquid developer Pending JPH07181749A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP5346504A JPH07181749A (en) 1993-12-22 1993-12-22 Liquid developer

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP5346504A JPH07181749A (en) 1993-12-22 1993-12-22 Liquid developer

Publications (1)

Publication Number Publication Date
JPH07181749A true JPH07181749A (en) 1995-07-21

Family

ID=18383875

Family Applications (1)

Application Number Title Priority Date Filing Date
JP5346504A Pending JPH07181749A (en) 1993-12-22 1993-12-22 Liquid developer

Country Status (1)

Country Link
JP (1) JPH07181749A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5981133A (en) * 1997-04-04 1999-11-09 Minolta Co., Ltd. Liquid developer and image forming apparatus

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS52126231A (en) * 1976-04-15 1977-10-22 Ricoh Co Ltd Liquid developer
JPS59221302A (en) * 1983-05-31 1984-12-12 Japan Synthetic Rubber Co Ltd Preparation of magnetic polymer particle
JPS61258273A (en) * 1985-05-13 1986-11-15 Ricoh Co Ltd Liquid developer for electrostatic photography
JPH0333866A (en) * 1989-06-30 1991-02-14 Ricoh Co Ltd Magnetic color toner
JPH03289666A (en) * 1990-04-06 1991-12-19 Ricoh Co Ltd Magnetic toner
JPH05134451A (en) * 1991-11-11 1993-05-28 Ricoh Co Ltd Magnetic toner and magnetic ink
JPH05265249A (en) * 1992-03-18 1993-10-15 Ricoh Co Ltd Magnetic toner
JPH05267042A (en) * 1992-03-17 1993-10-15 Ricoh Co Ltd Organic magnetic material, manufacture thereof and magnetic toner containing said material and magnetic ink
JPH0677037A (en) * 1992-07-09 1994-03-18 Xerox Corp Magnetic material and its production
JPH06100876A (en) * 1992-07-09 1994-04-12 Xerox Corp Magnetic fluid and production thereof

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS52126231A (en) * 1976-04-15 1977-10-22 Ricoh Co Ltd Liquid developer
JPS59221302A (en) * 1983-05-31 1984-12-12 Japan Synthetic Rubber Co Ltd Preparation of magnetic polymer particle
JPS61258273A (en) * 1985-05-13 1986-11-15 Ricoh Co Ltd Liquid developer for electrostatic photography
JPH0333866A (en) * 1989-06-30 1991-02-14 Ricoh Co Ltd Magnetic color toner
JPH03289666A (en) * 1990-04-06 1991-12-19 Ricoh Co Ltd Magnetic toner
JPH05134451A (en) * 1991-11-11 1993-05-28 Ricoh Co Ltd Magnetic toner and magnetic ink
JPH05267042A (en) * 1992-03-17 1993-10-15 Ricoh Co Ltd Organic magnetic material, manufacture thereof and magnetic toner containing said material and magnetic ink
JPH05265249A (en) * 1992-03-18 1993-10-15 Ricoh Co Ltd Magnetic toner
JPH0677037A (en) * 1992-07-09 1994-03-18 Xerox Corp Magnetic material and its production
JPH06100876A (en) * 1992-07-09 1994-04-12 Xerox Corp Magnetic fluid and production thereof

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5981133A (en) * 1997-04-04 1999-11-09 Minolta Co., Ltd. Liquid developer and image forming apparatus

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