JPH07113783B2 - Negatively charged developer for electrophotography - Google Patents
Negatively charged developer for electrophotographyInfo
- Publication number
- JPH07113783B2 JPH07113783B2 JP61287171A JP28717186A JPH07113783B2 JP H07113783 B2 JPH07113783 B2 JP H07113783B2 JP 61287171 A JP61287171 A JP 61287171A JP 28717186 A JP28717186 A JP 28717186A JP H07113783 B2 JPH07113783 B2 JP H07113783B2
- Authority
- JP
- Japan
- Prior art keywords
- fine powder
- silicic acid
- treated
- silicone oil
- toner
- 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.)
- Expired - Lifetime
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
- G03G9/097—Plasticisers; Charge controlling agents
- G03G9/09708—Inorganic compounds
- G03G9/09716—Inorganic compounds treated with organic compounds
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は電子写真，静電記録，静電印刷等に於ける静荷
電像を現像する為の負荷電性の電子写真用現像剤に関す
る。さらに詳しくは、直接法又は間接電子写真現像方法
に於いて均一に強く負電荷に帯電し、環境依存性の少な
い高品質な画像を与える負荷電性の電子写真用現像剤に
関する。The present invention relates to a negatively chargeable electrophotographic developer for developing an electrostatically charged image in electrophotography, electrostatic recording, electrostatic printing and the like. More specifically, it relates to a negatively chargeable electrophotographic developer which is uniformly and strongly negatively charged in a direct method or an indirect electrophotographic developing method and gives a high-quality image with little environmental dependence.
従来、電子写真法としては米国特許第2,297,691号明細
書、特公昭42-23910号公報（米国特許第3,666,363号明
細書）、特公昭43-24748号公報（米国特許第4,071,361
号明細書）等、多数の方法が知られているが、一般には
光導電性物質を利用し、種々の手段により感光体上に電
気的潜像を形成し、次いで該潜像を現像粉（以下トナー
と称す）を用いて現像し、必要に応じて紙等の転写材に
トナー画像を転写した後、加熱、圧力あるいは溶剤蒸気
などにより定着して複写物を得るものである。またトナ
ー画像を転写する工程を有する場合には、通常、感光体
上の残余のトナーを除去するための工程が設けられる。Conventionally, as an electrophotographic method, U.S. Pat.No. 2,297,691, Japanese Patent Publication No. 42-23910 (US Pat. No. 3,666,363), Japanese Patent Publication No. 43-24748 (US Pat. No. 4,071,361).
A number of methods are known, but generally, a photoconductive substance is used to form an electric latent image on a photoreceptor by various means, and then the latent image is developed with a powder ( (Hereinafter referred to as toner), the toner image is transferred to a transfer material such as paper, if necessary, and then fixed by heating, pressure or solvent vapor to obtain a copy. When the method has a step of transferring a toner image, it usually has a step of removing the residual toner on the photoconductor.
電気的潜像をトナーを用いて可視化する現像方法は、例
えば米国特許第2,874,063号明細書に記載されている磁
気ブラシ法、同2,618,552号明細書に記載されているカ
スケード現像法及び同2,221,776号明細書に記載されて
いる粉末雲法等がある。又、磁性トナーを使用する方法
として、米国特許第3,909,258号明細書に記載されてい
る導電性トナーを使用するマグネドライ法、トナー粒子
の誘電分極を使用する方法、トナーの撹乱による電荷移
送の方法、又、近年本出願人が提案した特開昭54-42141
号公報、特開昭55-18656号公報の如き潜像に対してトナ
ー粒子を飛翔させて現像する方法がある。A developing method for visualizing an electric latent image using toner is, for example, a magnetic brush method described in U.S. Pat.No. 2,874,063, a cascade developing method described in U.S. Pat. No. 2,618,552 and 2,221,776. The powder cloud method and the like described in the book are available. Further, as a method of using a magnetic toner, a magnet dry method using a conductive toner described in US Pat. No. 3,909,258, a method of using dielectric polarization of toner particles, a method of charge transfer by disturbance of toner In addition, Japanese Patent Laid-Open No. 54-42141 proposed by the present applicant in recent years
JP-A-55-18656 and JP-A-55-18656 disclose a method in which toner particles are made to fly to develop a latent image.
これらの現像法に適用するトナーとしては、従来、天然
あるいは合成樹脂中に染料、顔料を分散させた微粉末が
使用されている。例えば、ポリスチレンなどの結着樹脂
中に着色剤を分散させたものを１〜30μ程度に微粉砕し
た粒子がトナーとして用いられている。磁性トナーとし
てはマグネタイトなどの磁性体粒子を含有せしめたもの
が用いられている。いわゆる二成分現像剤を用いる方式
の場合には、トナーな通常、ガラスビーズ、鉄粉などの
キヤリアー粒子と混合して用いる。As a toner applied to these developing methods, a fine powder in which a dye or a pigment is dispersed in a natural or synthetic resin is conventionally used. For example, particles in which a colorant is dispersed in a binder resin such as polystyrene and finely pulverized to about 1 to 30 μm are used as a toner. A magnetic toner containing magnetic particles such as magnetite is used. In the case of using a so-called two-component developer, it is usually used as a toner mixed with carrier particles such as glass beads and iron powder.
この様な乾式現像剤を使用する方法において、良好な画
質の可視画像を形成するためには、現像剤が高い流動性
を有し、かつ均一な帯電性を有することが必要であり、
そのために従来よりケイ酸微粉体をトナー粉末に添加混
合することが行われている。然るにシリカ微粉体はその
ままでは親水性であるためにこれが添加された現像剤は
空気中の湿気により凝集を生じて流動性が低下したり、
甚だしい場合にはシリカの吸湿により現像剤の帯電性能
を低下させてしまう。そこで疎水化処理したシリカ微粉
体を用いることが特開昭46-5782号、特開昭48-47345
号、特開昭48-47346号等で提案されている。具体的には
ケイ酸微粉体とシランカツプリング剤を反応させ、ケイ
酸微粉体表面のシラノール基を他の有機基で置換し疎水
化する方法であり、シランカツプリング剤としては例え
ばジメチルジクロルシラン、トリメチルアルコオキシシ
ラン等が使用されている。In the method using such a dry developer, in order to form a visible image with good image quality, the developer needs to have high fluidity and have uniform chargeability,
Therefore, it has been customary to add fine silica powder to toner powder for mixing. However, since the silica fine powder is hydrophilic as it is, the developer to which the silica fine powder is added causes aggregation due to moisture in the air to lower the fluidity,
In extreme cases, moisture absorption of silica lowers the charging performance of the developer. Therefore, it is preferable to use a silica fine powder that has been subjected to a hydrophobic treatment.
And JP-A-48-47346. Specifically, it is a method of reacting a silicic acid fine powder with a silane coupling agent to substitute silanol groups on the surface of the silicic acid fine powder with another organic group to make it hydrophobic, and examples of the silane coupling agent include dimethyldichloro Silane, trimethylalcooxysilane, etc. are used.
しかしながら、これらのケイ酸微粉体は一応疎水化され
ているとはいうものの疎水化の程度が十分とはいえず、
高湿条件下に放置された場合現像剤の帯電性能が低下し
てしまう。又、近年小型で安価なパーソナルユースの複
写機、レーザープリンター等が出現し、これまでの様に
空調装置等で比較的環境条件の良いオフイス等だけでは
なく、一般家庭等でも使用される状況においては、長期
間の高湿条件下放置において良好なコピー品質を保つ必
要があり、この点でも従来の疎水化ケイ酸微粉体では性
能的に不満足なものであった。However, although these silica fine powders are tentatively hydrophobized, the degree of hydrophobization is not sufficient,
If left under high humidity conditions, the charging performance of the developer will deteriorate. In recent years, small and inexpensive personal-use copiers, laser printers, etc. have emerged, and are not only used in offices with relatively good environmental conditions such as air conditioners as in the past, but also in general households and the like. It is necessary to maintain good copy quality when left for a long period of time under high humidity conditions, and in this respect as well, the conventional hydrophobized silica fine powder was unsatisfactory in performance.
本発明者らは、種々のケイ酸微粉体について検討を行っ
た結果、好ましくは、シランカツプリング剤で処理され
た後、さらにA/25±A/30重量部（A:シリカ微粉体の比表
面積）のシリコンオイルで処理され、疎水化度が90％以
上のシリカ微粉体を使用することにより、上記問題点を
極めて良好に回避することができることを見出した。The present inventors, as a result of examining various silicic acid fine powder, preferably, after being treated with a silane coupling agent, further A / 25 ± A / 30 parts by weight (A: silica fine powder ratio It has been found that the above problems can be satisfactorily avoided by using silica fine powder having a hydrophobicity of 90% or more which is treated with silicon oil having a surface area of 90%.
すなわち、本発明の目的は高温高湿や低温低湿などの環
境変化に対しても安定であり、常に良好な特性を発揮す
ることのできる静電荷現像用現像剤を提供することにあ
る。That is, an object of the present invention is to provide a developer for electrostatic charge development that is stable against environmental changes such as high temperature and high humidity and low temperature and low humidity, and can always exhibit good characteristics.
本発明の他の目的は、現像，定着及びクリーニング等の
プロセスを含む電子写真法において、長期に亘って多数
の画像を形成した場合にも安定した画像が得られる。耐
久性に優れた現像剤を提供することにある。Another object of the present invention is to obtain a stable image even when a large number of images are formed over a long period in the electrophotographic method including processes such as development, fixing and cleaning. It is to provide a developer having excellent durability.
又、本発明の他の目的は、従来の荷電性トナーにまつわ
る種々の問題点を解決し、均一に強く帯電し、静電荷像
を可視化してカブリやエツジ周辺へのトナーの飛び散り
のない高品質の画像を与える現像剤を提供することにあ
る。Another object of the present invention is to solve various problems associated with the conventional chargeable toner, to uniformly and strongly charge, to visualize an electrostatic charge image, and to obtain a high quality toner without scattering of toner around fog or edge. It is to provide a developer that gives the image.
本発明は、ヘキサメチルジシラザンまたは下記式 RmSiYn ［式中、Ｒはアルコキシ基又は塩素原子を示し、ｍは１
〜３の整数を示し、Ｙはアルキル基を示し、ｎは３〜１
の整数を示す。］ で示されるシランカップリング剤で処理された後、さら
にシリコーンオイルで処理された負荷電性のケイ酸微粉
体と、トナーとを含有することを特徴とする負荷電性の
電子写真用現像剤に関する。The present invention includes hexamethyldisilazane or the following formula RmSiYn [wherein R represents an alkoxy group or a chlorine atom, and m is 1
To 3 are shown, Y is an alkyl group, and n is 3 to 1.
Indicates an integer. ] A negatively chargeable electrophotographic developer containing a toner and a negatively chargeable silicic acid fine powder further treated with silicone oil after being treated with a silane coupling agent represented by Regarding
好ましくは、シリコーンオイルによる処理量がシランカ
ップリング剤で処理された後のケイ酸微粉体100重量部
に対しA/25±A/30重量部（A:ケイ酸微粉体の比表面積）
であり、疎水化度が90％以上であることが、上記問題点
を良好に解消するのに良い。Preferably, A / 25 ± A / 30 parts by weight (A: specific surface area of the silica fine powder) per 100 parts by weight of the silicic acid fine powder after the amount treated with the silicone oil is treated with the silane coupling agent.
It is preferable that the degree of hydrophobicity is 90% or more in order to satisfactorily solve the above problems.
従来のシランカツプリング剤処理においては、ケイ酸微
粉体の全てのシラノール基をつぶすことは困難であり、
残存シラノール基の高湿下における水分吸着は反応後の
シランカツプリング剤分子による立体障害のみであり、
完全に残存シラノール基の水分吸着を防ぐことができな
い。In the conventional silane coupling agent treatment, it is difficult to destroy all silanol groups of the silicic acid fine powder,
Moisture adsorption of residual silanol groups under high humidity is only steric hindrance due to silane coupling agent molecules after the reaction,
It is impossible to completely prevent the residual silanol groups from absorbing water.
一方シリコンオイル処理においては、シリコンオイルが
ケイ酸微粉体の表面に塗布されることにより、シラノー
ル基を完全に覆いかくすことができ、耐湿性は飛躍的に
向上する。しかしながら、シリコンオイル処理のみで
は、ケイ酸微粉体表面を覆うためのシリコンオイル量が
多く、処理中にケイ酸微粉体の凝集体ができやすく、現
像剤に適用した場合現像剤の流動性が悪くなる等の欠点
を生じる。本発明者らは上記に鑑み、鋭意検討の結果、
良好な耐湿性を保ちつつ、ケイ酸微粉体の凝集体を除く
ためには、ケイ酸微粉体をシランカツプリング剤で処理
した後、少量のシリコンオイルで処理することにより上
記欠点を克服できることを見出したものである。On the other hand, in the silicone oil treatment, the silanol groups can be completely covered by coating the surface of the silicic acid fine powder with silicone oil, and the moisture resistance is dramatically improved. However, the silicone oil treatment alone causes a large amount of silicone oil to cover the surface of the silicic acid fine powder, and easily aggregates of the silicic acid fine powder during the treatment, resulting in poor fluidity of the developer when applied to the developer. It causes a defect such as In view of the above, the present inventors have earnestly studied,
In order to remove the agglomerates of fine silicic acid powder while maintaining good moisture resistance, it is possible to overcome the above drawbacks by treating the fine silicic acid powder with a silane coupling agent and then with a small amount of silicone oil. I found it.
又、本発明のケイ酸微粉体においては、最終的に負帯電
性の強いシリコンオイルでの処理が行われるため、ケイ
酸微粉体が強く負に帯電するため現像剤に添加した場
合、現像剤に強く均一な負荷電性を与えることができ
る。この特性は特に帯電の不安定になりやすい、磁性一
成分トナーには有効である。Further, since the silicic acid fine powder of the present invention is finally treated with silicone oil having a strong negative charge property, the silicic acid fine powder is strongly negatively charged. It can provide strong and uniform negative chargeability. This characteristic is particularly effective for magnetic one-component toner, which tends to have unstable charging.
本発明に用いられるケイ酸微粉体は、ケイ素ハロゲン化
合物の蒸気相酸化により生成されたいわゆる乾式法又は
ヒユームドシリカと称される乾式シリカ、及び水ガラス
等から製造されるいわゆる湿式シリカの両方が使用可能
であるが表面及びケイ酸微粉体の内部にあるシラノール
基が少なく、又Na2O,SO3 2-等の製造残査のない乾式シリ
カの方が好ましい。As the silicic acid fine powder used in the present invention, both a so-called dry process produced by vapor phase oxidation of a silicon halogen compound or a dry silica called fumed silica and a so-called wet silica produced from water glass or the like can be used. However, dry silica having less silanol groups on the surface and inside the silicic acid fine powder and having no production residue such as Na 2 O, SO 3 2− is preferable.
又、乾式シリカにおいては製造工程において例えば、塩
化アルミニウム又は、塩化チタンなど他の金属ハロゲン
化合物をケイ素ハロゲン化合物と共に用いる事によって
シリカと他の金属酸化物の複合微粉体を得る事も可能で
あり、それらも包含する。Further, in the case of dry silica, it is also possible to obtain a composite fine powder of silica and another metal oxide by using another metal halogen compound such as aluminum chloride or titanium chloride together with a silicon halogen compound in the manufacturing process. They are also included.
その粒径は平均の一次粒径として、0.001〜２μの範囲
内である事が望ましく、特に好ましくは、0.002〜0.2μ
の範囲内のシリカ微粉体を使用するのが良い。The average particle size of the particles is preferably in the range of 0.001 to 2μ, and particularly preferably 0.002 to 0.2μ.
It is preferable to use a fine silica powder within the range.
本発明に用いられるシランカップリング剤はヘキサメチ
ルジシラザンまたは一般式 RmSiYn R:アルコキシ基又は、塩素原子 m:1〜３の整数 Y:アルキル基 n:3〜１の整数 で示される、例えば代表的にはジメチルジクロルシラ
ン，トリメチルクロルシラン，ヘキサメチルジシラザン
等をあげることができる。The silane coupling agent used in the present invention is represented by hexamethyldisilazane or a general formula RmSiYn R: an alkoxy group, or a chlorine atom m: an integer of 1 to 3 Y: an alkyl group n: an integer of 3 to 1, for example Specific examples thereof include dimethyldichlorosilane, trimethylchlorosilane, hexamethyldisilazane, and the like.
上記ケイ酸微粉体のシランカツプリング剤処理は、ケイ
酸微粉体を撹拌等によりクラウド状としたものに気化し
たシランカツプリング剤を反応させる乾式処理又は、ケ
イ酸微粉体を溶媒中に分散させシランカツプリング剤を
滴下反応させる湿式法等一般に知られた方法で処理する
ことができる。The silane coupling agent treatment of the silicic acid fine powder is a dry treatment in which the vaporized silane coupling agent is reacted with the silicic acid fine powder made into a cloud by stirring or the like, or the silicic acid fine powder is dispersed in a solvent. The treatment can be carried out by a generally known method such as a wet method in which a silane coupling agent is dropped.
本発明に使用されるシリコンオイルは、一般に次の式で
示されるものであり、 R:C1〜３のアルキル基 Ｒ′：アルキル，ハロゲン変性アルキル，フエニル，変
性フエニル等のシリコンオイル変性基 Ｒ″：C1〜３のアルキル基又はアルコオキシ基 ｍ及びn:整数 例えば、ジメチルシリコンオイル，アルキル変性シリコ
ンオイル，α−メチルスチレン変性シリコンオイル，ク
ロルフエニルシリコンオイル，フツ素変性シリコンオイ
ル等が上げられる。又、上記シリコンオイルは好ましく
は25℃における粘度がおよそ50〜1000センチストークス
のものが用いられる。分子量が低すぎるシリコンオイル
は加熱処理等により、揮発分が発生することがあり、
又、分子量が高すぎると粘度が高くなりすぎ処理操作が
しにくくなる。The silicone oil used in the present invention is generally represented by the following formula: R: C 1 ~ 3 alkyl group R ': alkyl, halogen-modified alkyl, phenyl, silicone oil modified group R of the modified phenyl such as ": an alkyl group of C 1 ~ 3 or Arukookishi group and m and n: an integer such as dimethyl silicone Oil, alkyl modified silicone oil, α-methylstyrene modified silicone oil, chlorophenyl silicone oil, fluorine modified silicone oil, etc. The above silicone oil preferably has a viscosity of about 50 to 1000 centistokes at 25 ° C. Silicone oil with too low molecular weight may generate volatile components due to heat treatment, etc.
On the other hand, if the molecular weight is too high, the viscosity becomes too high and the treatment operation becomes difficult.
シリコンオイル処理の方法は公知の技術が用いられ、例
えばシリカ微粉体とシリコンオイルとをヘンシエルミキ
サー等の混合機を用いて直接混合しても良いし、ベース
シリカへシリコンオイルを噴霧する方法によっても良
い。あるいは適当な溶剤にシリコンオイルを溶解あるい
は分散せしめた後、ベースのシリカ微粉体とを混合した
後、溶剤を除去して作成しても良い。A known technique is used for the method of treating silicon oil. For example, fine silica powder and silicone oil may be directly mixed using a mixer such as a Henschel mixer, or a method of spraying silicone oil onto the base silica may be used. Is also good. Alternatively, it may be prepared by dissolving or dispersing silicon oil in an appropriate solvent, mixing with silica fine powder of the base, and then removing the solvent.
本発明の重要なポイントととして、ケイ酸微粉体の処理
の順序がある。本発明のケイ酸微粉体はまず、シランカ
ツプリング剤で処理した後にシリコンオイル処理する必
要がある。シリコンオイル処理後シランカツプリング処
理では、シランカツピリング剤がケイ酸微粉体表面のシ
ラノール基と反応できず、遊離のシランカツプリング剤
ができてしまう。又製造上好ましい方法として、シラン
カツプリング剤、シリコンオイルの同時処理が考えられ
るが、同時処理を行うとケイ酸微粉体の疎水化がうまく
ゆかず、充分に疎水化したケイ酸微粉体を得ることがで
きない。この理由はさだかではないが、シリコンオイル
の付着とシランカツプリング剤の反応が競争反応となる
ことによりシランカツプリング剤がケイ酸微粉体のシラ
ノール基と反応できず遊離のシランカツプリング剤がで
きる。又は、シリコンオイルとシランカツプリング剤の
反応がおこってしまうことも考えられる。An important point of the present invention is the order of treatment of the silica fine powder. The silicic acid fine powder of the present invention must first be treated with a silane coupling agent and then treated with silicone oil. In the silane coupling treatment after the silicone oil treatment, the silane coupling agent cannot react with the silanol groups on the surface of the silicic acid fine powder, and a free silane coupling agent is formed. Simultaneous treatment of a silane coupling agent and silicone oil is considered as a preferable method in production, but the simultaneous treatment does not successfully hydrophobize the silicic acid fine powder, and a sufficiently hydrophobized silicic acid fine powder is obtained. I can't. The reason for this is not critical, but the adhesion of silicone oil and the reaction of the silane coupling agent become a competitive reaction, so that the silane coupling agent cannot react with the silanol groups of the silicic acid fine powder to form a free silane coupling agent. . Alternatively, the reaction between the silicone oil and the silane coupling agent may occur.
本発明におけるシリカ微粉体の疎水化度は、以下の方法
で測定される。密栓式の容器に純水100ml及び試料1gを
入れ、振とう機にて10分間振とうする。振とう後静置
し、シリカ粉末層と水層が分離した後水層を採取し、50
0mmの波長でシリカ微粉体を入れていないブランクの純
水を基準として透過率を測定し、その透過率の値をもっ
て処理シリカの疎水化度とする。The degree of hydrophobicity of the silica fine powder in the present invention is measured by the following method. Put 100 ml of pure water and 1 g of sample in a tightly closed container, and shake with a shaker for 10 minutes. Shake and let stand, collect the aqueous layer after separating the silica powder layer and aqueous layer,
The transmittance is measured at a wavelength of 0 mm with reference to pure pure water containing no silica fine powder, and the value of the transmittance is used as the hydrophobicity of the treated silica.
本発明におけるシリカ微粉体の疎水化度は、90％以上
（好ましくは95％以上）であることが望ましい。疎水化
度がこれ以下であると、高湿下でのシリカ微粉体の水分
吸着により高品位の画像が得られなくなる。The degree of hydrophobicity of the silica fine powder in the present invention is preferably 90% or more (preferably 95% or more). If the degree of hydrophobicity is less than this, it becomes impossible to obtain a high-quality image due to moisture adsorption of the silica fine powder under high humidity.
本発明におけるシランカツプリング剤の処理量は、シラ
ンカツプリング剤での処理の段階で疎水化率が低いと、
次のシリコンオイル処理段階で多量のシリコンオイルが
必要となるため、用いるカツプリング剤のハロゲン基，
アルコオキシ基の数によっても異なるがケイ素酸化物微
粉体のシラノール基の数（一般に乾式シリカでは２〜３
個Å２）を考慮し、50％以上より好ましくは70％以上の
シラノール基と反応できる量を用いるべきである。The treatment amount of the silane coupling agent in the present invention is such that the hydrophobicity is low at the stage of the treatment with the silane coupling agent,
Since a large amount of silicone oil is required in the next silicone oil treatment step, the halogen group of the coupling agent used,
The number of silanol groups in the silicon oxide fine powder (generally 2-3 in the case of dry silica) varies depending on the number of alcooxy groups.
In consideration of the number of particles 2 ), an amount which can react with 50% or more, more preferably 70% or more of silanol groups should be used.
又、シリコンオイルの処理量は、前段階で一応ケイ酸微
粉体が疎水化されているため、少量で良く、A/25±A/30
（A:ケイ酸微粉体の比表面積）、より好ましくはA/25±
A/40の範囲にすることが好ましい。ここでケイ酸微粉体
の比表面積とはBET法におけるN2吸着から求めた値であ
る。上記処理量を限定した理由は、シリコンオイル処理
量が少なすぎると、シランカツプリング剤処理のみと同
一の結果となり耐湿性が向上せず高湿下ではケイ酸微粉
体が吸湿してしまい高品位のコピー画像が得られなくな
る。又、シリコンオイル処理量が多すぎると、前述のケ
イ酸微粉体の凝集体ができやすくなり、又、はなはだし
くは遊離のシリコンオイルができてしまうため、現像剤
に適用した場合流動性を向上することができない等の欠
点が生じる。In addition, the amount of silicon oil to be treated can be small, because the fine silica powder has been made hydrophobic in the previous stage.
(A: specific surface area of silicic acid fine powder), more preferably A / 25 ±
It is preferably in the range of A / 40. Here, the specific surface area of the silicic acid fine powder is a value obtained from N 2 adsorption in the BET method. The reason for limiting the above treatment amount is that if the treatment amount of silicone oil is too small, the same result as that of the treatment with the silane coupling agent will not be obtained, and the moisture resistance will not improve, and the silica fine powder will absorb moisture under high humidity, resulting in high quality. You will not be able to obtain a copy image of. Further, if the amount of treated silicone oil is too large, the agglomerates of the above-mentioned fine particles of silicic acid are likely to be formed, and furthermore, free silicone oil is produced, so that the fluidity is improved when applied to a developer. There are drawbacks such as the inability to do so.
これらの処理されたケイ酸微粉体の現像剤に対する適用
量は現像剤（トナー）100重量部に対して0.01〜20重量
部、より好ましくは0.1〜３重量部である。The amount of the treated silica fine powder applied to the developer is 0.01 to 20 parts by weight, more preferably 0.1 to 3 parts by weight, based on 100 parts by weight of the developer (toner).
本発明に用いられるトナーの結着樹脂としては、ポリス
チレン、ポリｐ−クロルスチレン、ポリビニルトルエ
ン、スチレン−ｐクロルスチレン共重合体、スチレンビ
ニルトルエン共重合体等のスチレン及びその置換体の単
独重合体及びそれらの共重合体；スチレン−アクリル酸
メチル共重合体、スチレン−アクリル酸エチル共重合
体、スチレン−アクリル酸ｎ−ブチル共重合体等のスチ
レンとアクリル酸エステルとの共重合体；スチレン−メ
タクリル酸メチル共重合体、スチレン−メタクリル酸エ
チル共重合体、スチレン−メタクリル酸ｎ−ブチル共重
合体等のスチレンとメタクリル酸エステルとの共重合
体；スチレンとアクリル酸エステル及びメタクリル酸エ
ステルとの多元共重合体；その他スチレン−アクリロニ
トリル共重合体、スチレン−ビニルメチルエーテル共重
合体、スチレン−ブタジエン共重合体、スチレン−ビニ
ルメチルケトン共重合体、スチレン−アクリロニトリル
−インデン共重合体、スチレン−マレイン酸エステル共
重合体等のスチレンと他のビニル系モノマーとのスチレ
ン系共重合体；ポリメチルメタクリレート、ポリブチル
メタクリレート、ポリ酢酸ビニル、ポリエステル、ポリ
アミド、エポキシ樹脂、ポリビニルブチラール、ポリア
クリル酸、フエノール樹脂、脂肪属又は脂環族炭化水素
樹脂、石油樹脂、塩素化パラフイン等が単独または混合
して使用出来る。Examples of the binder resin of the toner used in the present invention include homopolymers of styrene and its substitution products such as polystyrene, poly-p-chlorostyrene, polyvinyltoluene, styrene-p-chlorostyrene copolymer, and styrene-vinyltoluene copolymer. And copolymers thereof; copolymers of styrene and acrylic ester such as styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-n-butyl acrylate copolymer; styrene- Copolymers of styrene and methacrylic acid ester such as methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-n-butyl methacrylate copolymer; of styrene and acrylic acid ester and methacrylic acid ester Multi-component copolymer; other styrene-acrylonitrile copolymer, styrene -Styrene and other vinyl-based monomers such as vinyl methyl ether copolymer, styrene-butadiene copolymer, styrene-vinyl methyl ketone copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid ester copolymer Styrene-based copolymer with; polymethylmethacrylate, polybutylmethacrylate, polyvinyl acetate, polyester, polyamide, epoxy resin, polyvinyl butyral, polyacrylic acid, phenol resin, aliphatic or alicyclic hydrocarbon resin, petroleum resin, Chlorinated paraffin and the like can be used alone or in combination.
特に圧力定着方式に供せられるトナー用の結着樹脂とし
て、低分子ポリエチレン、低分子量ポリプロピレン、エ
チレン−酢酸ビニル共重合体、エチレン−アクリル酸エ
ステル共重合体、高級脂肪酸、ポリアミド樹脂、ポリエ
ステル樹脂等が単独または混合して使用出来る。In particular, as a binder resin for toner that is subjected to a pressure fixing method, low molecular weight polyethylene, low molecular weight polypropylene, ethylene-vinyl acetate copolymer, ethylene-acrylic acid ester copolymer, higher fatty acid, polyamide resin, polyester resin, etc. Can be used alone or in combination.
用いる重合体、共重合体、あるいはポリマーブレンド
は、スチレンに代表されるビニル芳香族系またはアクリ
ル系のモノマーを40wt％以上の量で含有すると、より望
ましい結果が得られる。When the polymer, copolymer or polymer blend used contains a vinyl aromatic or acrylic monomer represented by styrene in an amount of 40 wt% or more, more desirable results are obtained.
トナーには、任意の適当な顔料や染料が着色剤として使
用できる。例えば、カーボンブラツク、鉄黒、フタルシ
アニンブルー、郡青、キナクリドン、ベンジジンイエロ
ーなど公知の染顔料がある。Any suitable pigment or dye can be used as a colorant in the toner. For example, there are known dyes and pigments such as carbon black, iron black, phthalcyanine blue, county blue, quinacridone, and benzidine yellow.
トナーを磁性トナーとする場合には、鉄、コバルト、ニ
ツケルなどの強磁性元素、あるいは、マグネタイト、ヘ
マタイト、フエライトなどの鉄、コバルト、ニツケル、
マンガンなどの合金や化合物、その他の強磁性合金など
の磁性体を含有せしめればよい。When the toner is a magnetic toner, a ferromagnetic element such as iron, cobalt, nickel, or iron, cobalt, nickel, such as magnetite, hematite, or ferrite,
An alloy or compound such as manganese, or a magnetic material such as another ferromagnetic alloy may be contained.
トナーには必要に応じて添加剤を混合しても良い。その
ような添加剤としては例えばテフロン、ステアリン酸亜
鉛の如き滑剤、あるいは定着助剤（例えば低分子量ポリ
エチレンなど）、あるいは導電性付与剤として酸化スズ
の如き金属酸化物等がある。You may mix an additive with a toner as needed. Examples of such additives include lubricants such as Teflon and zinc stearate, fixing aids (such as low molecular weight polyethylene), and metal oxides such as tin oxide as a conductivity-imparting agent.
以上本発明の基本的な構成と特色について述べたが以下
実施例にもとづいて具体的に本発明の方法について説明
する。しかしながら、これによって本発明の実施の態様
がなんら限定されるものではない。実施例中の部数は重
量部である。The basic structure and features of the present invention have been described above, but the method of the present invention will be specifically described below based on Examples. However, this does not limit the embodiments of the present invention in any way. The numbers of parts in the examples are parts by weight.
〔実施例１〕 上記混合物をロールミルで150℃〜160℃で混練し、冷却
後周知の方法でジエツトミル粉砕、風力分級を行い５〜
20μの磁性トナー分級品を得た。[Example 1] The above mixture is kneaded with a roll mill at 150 ° C to 160 ° C, cooled, and then subjected to a jet mill pulverization and air classification by a well-known method.
A 20 μm magnetic toner classified product was obtained.
次に比表面積200m2/gのケイ酸微粉体アエロジル＃200
（日本アエロジル社製）100部にヘキサメチルジシラザ
ン（HMDS）20部で処理を行った後（ヘキサメチルジシラ
ザン処理されたケイ酸微粉体の比表面積は約190m2/gで
あり、シラノール基の50％以上が反応していた）、ジメ
チルシリコンオイルKF-96 100cs（信越化学製）10部を
溶剤で希釈したもので処理を行い、乾燥後約250℃で加
熱処理を行い、ヘキサメチルジシラザン処理後ジメチル
シリコンオイルで処理された負帯電性のケイ酸微粉体を
得、前述の磁性トナー分級品100部に対し0.4部外添して
負帯電性の磁性トナー（すなわち、負帯電性の電子写真
用現像剤）を得た。この処理ケイ酸微粉体の疎水化度は
99％であった。この磁性トナーを市販の複写機セレツク
ス60AZ（コピア製）を用いて画出し試験を行ったとこ
ろ、画像濃度は常温常湿（23℃60％RH）の条件下では、
1.3〜1.4程度であった。これを高温高湿条件（32.5℃90
％）下に放置し、画出し試験を行ったところ、放置朝一
で画像濃度1.2,一週間放置しても画像濃度は1.1程度で
あった。又、耐久試験においても高温高湿，低温低湿の
各環境下で、各１万枚の耐久を行ったが良好な画像が得
られた。Next, fine silica powder Aerosil # 200 with a specific surface area of 200 m 2 / g
After treating 100 parts (manufactured by Nippon Aerosil Co., Ltd.) with 20 parts of hexamethyldisilazane (HMDS) (the specific surface area of the hexamethyldisilazane-treated fine silicate powder is about 190 m 2 / g, the silanol group is 50% or more of the above was reacted), 10 parts of dimethyl silicone oil KF-96 100cs (manufactured by Shin-Etsu Chemical Co., Ltd.) was treated with a solvent, dried and then heat-treated at about 250 ° C. After the silazane treatment, a negatively chargeable silicic acid fine powder treated with dimethyl silicone oil was obtained, and 0.4 part was externally added to 100 parts of the above-mentioned magnetic toner classification product to obtain a negatively chargeable magnetic toner (that is, a negatively chargeable magnetic toner). A developer for electrophotography) was obtained. The hydrophobicity of this treated silicic acid fine powder is
It was 99%. When this magnetic toner was subjected to an image output test using a commercially available copying machine Serexx 60AZ (manufactured by Copia), the image density was normal temperature and normal humidity (23 ° C. 60% RH).
It was about 1.3 to 1.4. High temperature and high humidity conditions (32.5 ℃ 90
%), The image density was 1.2 in one morning and about 1.1 in one week. Also, in the durability test, 10,000 images were endured under each environment of high temperature and high humidity and low temperature and low humidity, and good images were obtained.
〔実施例２〕 処理ケイ酸微粉体を比表面積200m2/gのケイ酸微粉体100
部にヘキサメチルジシラザン20部、シリコンオイルKF-9
6 3部とした以外は〔実施例１〕と同様の試験を行っ
た。このケイ酸微粉体の疎水化率は95％であり、高温高
湿下に放置した場合も一週間放置で画像濃度1.0〜1.1で
あり、良好であった。又、各環境での耐久においても問
題はなかった。[Example 2] The treated silicic acid fine powder was treated with a silicic acid fine powder 100 having a specific surface area of 200 m 2 / g.
20 parts of hexamethyldisilazane, silicone oil KF-9
The same test as in [Example 1] was conducted except that the amount was 63 parts. The hydrophobicity of this silicic acid fine powder was 95%, and the image density was 1.0 to 1.1 when left for 1 week even when left under high temperature and high humidity, which was good. Also, there was no problem in durability in each environment.
〔比較例１〕 処理ケイ酸微粉体を比表面積200m2/gのケイ酸微粉体100
部にヘキサメチルジシラザン20部を反応させたものに変
えた以外は〔実施例１〕と同様な試験を行ったところ、
処理ケイ酸微粉体の疎水化度は98％であり、常温常湿で
は画像濃度1.3の良な画像が得られたが高温高湿放置１
日で1.0,一週間放置で0.7まで画像濃度が下がってしま
った。[Comparative Example 1] The treated silicic acid fine powder was treated with a silicic acid fine powder 100 having a specific surface area of 200 m 2 / g.
When a test similar to that of [Example 1] was conducted, except that 20 parts of hexamethyldisilazane was reacted with 10 parts,
The hydrophobicity of the treated silicic acid fine powder was 98%, and a good image with an image density of 1.3 was obtained at room temperature and normal humidity, but it was left at high temperature and high humidity.
The image density decreased to 1.0 in a day and 0.7 after left for one week.
〔比較例２〕 比表面積200m2/gのケイ酸微粉体100部にヘキサメチルジ
シラザン20部，シリコンオイル10部を同時に処理した以
外は〔実施例１〕と同様な試験を行った。この処理によ
ってできた処理ケイ酸微粉体の疎水化度は67％であり、
高温高湿放置１日で画像濃度は0.9,一週間放置で0.6ま
で下がってしまった。[Comparative Example 2] The same test as in [Example 1] was conducted except that 100 parts of silicic acid fine powder having a specific surface area of 200 m 2 / g was simultaneously treated with 20 parts of hexamethyldisilazane and 10 parts of silicone oil. The hydrophobicity of the treated silicic acid fine powder produced by this treatment is 67%,
The image density was 0.9 after 1 day of high temperature and high humidity, and dropped to 0.6 after left for 1 week.
〔実施例３〕 比表面積300m2/gのケイ酸微粉体アエロジル＃300（日本
アエロジル社製）100部にヘキサメチレンジシラザン30
部を使用して処理後（ヘキサメチルジシラザン処理され
たケイ酸微粉体の比表面積は約280m2/gであり、シラノ
ール基の50％以上が反応していた）、さらにα−メチル
スチレン変性シリコンオイル（信越化学製KF-410）20部
で処理を行い、処理ケイ酸微粉体を得た。この疎水化度
は97％であった。この処理ケイ酸微粉体を0.3部〔実施
例１〕の分級品に外添し、〔実施例１〕と同様の画出し
テストを行ったところ、常温常湿で1.2〜1.3,高温高湿
放置１週間でも1.0〜1.1の画像濃度を得られ、各環境の
耐久テスト１万枚でも良好であった。Example 3 Hexamethylene disilazane 30 was added to 100 parts of silica fine powder Aerosil # 300 (manufactured by Nippon Aerosil Co., Ltd.) having a specific surface area of 300 m 2 / g.
After treatment with hexamethyldisilazane (the specific surface area of the silicic acid fine powder treated with hexamethyldisilazane was about 280 m 2 / g, 50% or more of the silanol groups had reacted), and then further modified with α-methylstyrene Treatment with 20 parts of silicone oil (KF-410 manufactured by Shin-Etsu Chemical) was performed to obtain treated silicic acid fine powder. The hydrophobicity was 97%. 0.3 part of this treated silicic acid fine powder was externally added to the classified product of [Example 1], and the same image formation test as in [Example 1] was conducted. An image density of 1.0 to 1.1 was obtained even after leaving for 1 week, and the durability test of 10,000 sheets in each environment was also good.
〔比較例３〕 〔実施例３〕に使用した原材料をα−メチルスチレン変
性シリコンオイル30部にした以外は同様の処理を行い、
処理ケイ酸微粉体を得（疎水化度98％）〔実施例３〕と
同様分級品に外添を行ったがシリカの凝集体がみられ、
流動性も悪く、現像剤の現像スリーブコートにムラが見
られた。[Comparative Example 3] The same treatment was carried out except that 30 parts of α-methylstyrene-modified silicone oil was used as the raw material used in [Example 3],
The treated silicic acid fine powder was obtained (hydrophobicity 98%), and the classified product was externally added in the same manner as in [Example 3], but aggregates of silica were observed.
The fluidity was also poor, and unevenness was observed in the developing sleeve coat of the developer.
〔実施例４〕 市販のジメチルジクロルシラン処理ケイ酸微粉体R-972
（日本アエロジル製）100部にジメチルシリコンオイル
（KF-96信越化学製）５部を〔実施例１〕と同様に処理
した。（疎水化度96％）この処理ケイ酸微粉体を〔実施
例１〕の分級品に0.4部外添し、〔実施例１〕と同様の
画出し試験を行ったところ、高温高湿条件下１週間放置
後でも画像濃度は1.1以上あり良好であった。又、各環
境下で耐久試験でも良好な結果が得られた。[Example 4] Commercially available dimethyldichlorosilane-treated silicic acid fine powder R-972
100 parts (manufactured by Nippon Aerosil) and 5 parts of dimethyl silicone oil (manufactured by KF-96 Shin-Etsu Chemical) were treated in the same manner as in [Example 1]. (Hydrophobicity 96%) 0.4 parts of this treated silicic acid fine powder was externally added to the classified product of [Example 1], and the same image development test as in [Example 1] was conducted. The image density was 1.1 or more, which was good even after left for one week. Also, good results were obtained in durability tests under each environment.
本発明の現像剤によれば、高温高湿、低温低湿等の環境
下においても高濃度であり、かつカブリや潜像周辺への
飛び散りのない高品質の画像が得られる。According to the developer of the present invention, it is possible to obtain a high-quality image which has a high density even in an environment of high temperature and high humidity, low temperature and low humidity, and which is free from fog and scattering around the latent image.
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 昭60−23863（ＪＰ，Ａ) 特開 昭58−216252（ＪＰ，Ａ) 特開 昭59−231550（ＪＰ，Ａ) ─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP-A-60-23863 (JP, A) JP-A-58-216252 (JP, A) JP-A-59-231550 (JP, A)
Claims (2)
〜３の整数を示し、Ｙはアルキル基を示し、ｎは３〜１
の整数を示す。］ で示されるシランカップリング剤で処理された後、さら
にシリコーンオイルで処理された負荷電性のケイ酸微粉
体と、トナーとを含有することを特徴とする負荷電性の
電子写真用現像剤。1. Hexamethyldisilazane or the following formula RmSiYn [wherein R represents an alkoxy group or a chlorine atom, and m is 1]
To 3 are shown, Y is an alkyl group, and n is 3 to 1.
Indicates an integer. ] A negatively chargeable electrophotographic developer containing a toner and a negatively chargeable silicic acid fine powder further treated with silicone oil after being treated with a silane coupling agent represented by .
ップリング剤で処理された後のケイ酸微粉体100重量部
に対しA/25±A/30重量部（A:ケイ酸微粉体の比表面積）
であり、疎水化度が90％以上であることを特徴とする特
許請求の範囲第１項記載の電子写真用現像剤。2. A / 25 ± A / 30 parts by weight (A: specific surface area of the silica fine powder) based on 100 parts by weight of the silicic acid fine powder after treated with a silane coupling agent in the amount treated with silicone oil.
The electrophotographic developer according to claim 1, wherein the degree of hydrophobicity is 90% or more.
Priority Applications (7)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61287171A JPH07113783B2 (en) | 1986-12-01 | 1986-12-01 | Negatively charged developer for electrophotography |
| DE3750157T DE3750157T2 (en) | 1986-12-01 | 1987-11-30 | Developer for the development of electrostatic latent images and imaging processes. |
| EP87117703A EP0270063B1 (en) | 1986-12-01 | 1987-11-30 | Developer for developing electrostatic latent image and image forming method |
| SG1995905816A SG28376G (en) | 1986-12-01 | 1987-11-30 | Developer for developing electrostatic latent image and image forming method |
| US07/128,263 US4868084A (en) | 1986-12-01 | 1987-12-01 | Developer for developing electrostatic latent image and image forming method |
| US07/375,467 US4906548A (en) | 1986-12-01 | 1989-07-05 | Developer for developing electrostatic latent image and image forming method |
| HK59795A HK59795A (en) | 1986-12-01 | 1995-04-20 | Developer for developing electrostatic latent image and image forming method. |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61287171A JPH07113783B2 (en) | 1986-12-01 | 1986-12-01 | Negatively charged developer for electrophotography |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63139367A JPS63139367A (en) | 1988-06-11 |
| JPH07113783B2 true JPH07113783B2 (en) | 1995-12-06 |
Family
ID=17713996
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61287171A Expired - Lifetime JPH07113783B2 (en) | 1986-12-01 | 1986-12-01 | Negatively charged developer for electrophotography |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07113783B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003176122A (en) * | 2001-09-13 | 2003-06-24 | Wacker Chemie Gmbh | Silica with low silanol group content |
| JP2008127253A (en) * | 2006-11-22 | 2008-06-05 | Sumitomo Osaka Cement Co Ltd | Surface-treated inorganic oxide particle, method for producing the same, dispersion liquid of the same and resin composition |
Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2835650B2 (en) * | 1989-06-28 | 1998-12-14 | アグファ ゲヴェルト ナームロゼ ベンノートチャップ | Dry electrostatic recording toner composition |
| JP2737022B2 (en) * | 1990-04-27 | 1998-04-08 | キヤノン株式会社 | Non-magnetic toner |
| JP2704784B2 (en) * | 1990-05-31 | 1998-01-26 | キヤノン株式会社 | Negatively chargeable non-magnetic toner and image forming method |
| JP2704785B2 (en) * | 1990-06-07 | 1998-01-26 | キヤノン株式会社 | Negatively chargeable non-magnetic toner and image forming method |
| JP2715334B2 (en) * | 1990-08-28 | 1998-02-18 | キヤノン株式会社 | Image forming method |
| US5424810A (en) * | 1991-09-13 | 1995-06-13 | Canon Kabushiki Kaisha | Magnetic toner, magnetic developer, apparatus unit, image forming apparatus and facsimile apparatus |
| US5447815A (en) * | 1992-06-04 | 1995-09-05 | Canon Kabushiki Kaisha | Developer for developing electrostatic image and image forming method |
| JP4828032B2 (en) * | 2001-03-05 | 2011-11-30 | 株式会社トクヤマ | Hydrophobic silica powder and method for producing the same |
| JP5953861B2 (en) | 2012-03-23 | 2016-07-20 | 富士ゼロックス株式会社 | Electrostatic image developing toner, electrostatic image developer, toner cartridge, developer cartridge, process cartridge, image forming apparatus, and image forming method |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58216252A (en) * | 1982-06-11 | 1983-12-15 | Nippon Aerojiru Kk | Dry type toner |
| JPH0727272B2 (en) * | 1983-06-14 | 1995-03-29 | キヤノン株式会社 | Development method |
| JPS6023863A (en) * | 1983-07-19 | 1985-02-06 | Canon Inc | Formation of image |
-
1986
- 1986-12-01 JP JP61287171A patent/JPH07113783B2/en not_active Expired - Lifetime
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003176122A (en) * | 2001-09-13 | 2003-06-24 | Wacker Chemie Gmbh | Silica with low silanol group content |
| JP2008189545A (en) * | 2001-09-13 | 2008-08-21 | Wacker Chemie Ag | Silica with low content of silanol group |
| JP2008127253A (en) * | 2006-11-22 | 2008-06-05 | Sumitomo Osaka Cement Co Ltd | Surface-treated inorganic oxide particle, method for producing the same, dispersion liquid of the same and resin composition |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63139367A (en) | 1988-06-11 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EXPY | Cancellation because of completion of term |