JPH04296765A - Toner for developing electrostatic charge image - Google Patents
Toner for developing electrostatic charge imageInfo
- Publication number
- JPH04296765A JPH04296765A JP3084589A JP8458991A JPH04296765A JP H04296765 A JPH04296765 A JP H04296765A JP 3084589 A JP3084589 A JP 3084589A JP 8458991 A JP8458991 A JP 8458991A JP H04296765 A JPH04296765 A JP H04296765A
- Authority
- JP
- Japan
- Prior art keywords
- toner
- magnetic toner
- electrostatic charge
- conductive magnetic
- developing
- 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
- 239000006247 magnetic powder Substances 0.000 claims abstract description 8
- 239000002245 particle Substances 0.000 description 20
- 230000000052 comparative effect Effects 0.000 description 17
- 238000011161 development Methods 0.000 description 17
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 10
- 229920005989 resin Polymers 0.000 description 8
- 239000011347 resin Substances 0.000 description 8
- 239000006229 carbon black Substances 0.000 description 7
- 239000011230 binding agent Substances 0.000 description 6
- 239000000463 material Substances 0.000 description 6
- 239000000377 silicon dioxide Substances 0.000 description 5
- 238000012546 transfer Methods 0.000 description 5
- 238000000034 method Methods 0.000 description 4
- 108091008695 photoreceptors Proteins 0.000 description 4
- 229910002012 Aerosil® Inorganic materials 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 3
- 230000002209 hydrophobic effect Effects 0.000 description 3
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 239000000654 additive Substances 0.000 description 2
- 230000000996 additive effect Effects 0.000 description 2
- 239000004020 conductor Substances 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 230000018044 dehydration Effects 0.000 description 2
- 238000006297 dehydration reaction Methods 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000006698 induction Effects 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- -1 polyethylene Polymers 0.000 description 2
- 238000006116 polymerization reaction Methods 0.000 description 2
- 238000010557 suspension polymerization reaction Methods 0.000 description 2
- 229920001169 thermoplastic Polymers 0.000 description 2
- 239000004416 thermosoftening plastic Substances 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- 229910000859 α-Fe Inorganic materials 0.000 description 2
- 229920000178 Acrylic resin Polymers 0.000 description 1
- 239000004925 Acrylic resin Substances 0.000 description 1
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- 229920000877 Melamine resin Polymers 0.000 description 1
- 239000004698 Polyethylene Substances 0.000 description 1
- 239000004721 Polyphenylene oxide Substances 0.000 description 1
- 239000004743 Polypropylene Substances 0.000 description 1
- 239000004793 Polystyrene Substances 0.000 description 1
- 229920001328 Polyvinylidene chloride Polymers 0.000 description 1
- 229920001807 Urea-formaldehyde Polymers 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- 229910052788 barium Inorganic materials 0.000 description 1
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 239000012461 cellulose resin Substances 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 229920006026 co-polymeric resin Polymers 0.000 description 1
- 239000003086 colorant Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 210000005069 ears Anatomy 0.000 description 1
- 229920001971 elastomer Polymers 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 238000010556 emulsion polymerization method Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000003822 epoxy resin Substances 0.000 description 1
- 239000002223 garnet Substances 0.000 description 1
- LNEPOXFFQSENCJ-UHFFFAOYSA-N haloperidol Chemical compound C1CC(O)(C=2C=CC(Cl)=CC=2)CCN1CCCC(=O)C1=CC=C(F)C=C1 LNEPOXFFQSENCJ-UHFFFAOYSA-N 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000009396 hybridization Methods 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- SZVJSHCCFOBDDC-UHFFFAOYSA-N iron(II,III) oxide Inorganic materials O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 description 1
- 229910052744 lithium Inorganic materials 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 description 1
- 238000010299 mechanically pulverizing process Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- NYGZLYXAPMMJTE-UHFFFAOYSA-M metanil yellow Chemical group [Na+].[O-]S(=O)(=O)C1=CC=CC(N=NC=2C=CC(NC=3C=CC=CC=3)=CC=2)=C1 NYGZLYXAPMMJTE-UHFFFAOYSA-M 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 229920001568 phenolic resin Polymers 0.000 description 1
- 239000005011 phenolic resin Substances 0.000 description 1
- 229920000058 polyacrylate Polymers 0.000 description 1
- 229920002239 polyacrylonitrile Polymers 0.000 description 1
- 239000004417 polycarbonate Substances 0.000 description 1
- 229920000515 polycarbonate Polymers 0.000 description 1
- 229920000647 polyepoxide Polymers 0.000 description 1
- 229920000728 polyester Polymers 0.000 description 1
- 229920000570 polyether Polymers 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 229920000193 polymethacrylate Polymers 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 229920002223 polystyrene Polymers 0.000 description 1
- 239000005033 polyvinylidene chloride Substances 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 150000003242 quaternary ammonium salts Chemical class 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 229910052596 spinel Inorganic materials 0.000 description 1
- 239000011029 spinel Substances 0.000 description 1
- 238000001694 spray drying Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 238000010558 suspension polymerization method Methods 0.000 description 1
- 229920005992 thermoplastic resin Polymers 0.000 description 1
- 229920001187 thermosetting polymer Polymers 0.000 description 1
- 229910052720 vanadium Inorganic materials 0.000 description 1
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 description 1
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 description 1
- 229920002554 vinyl polymer Polymers 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
Landscapes
- Developing Agents For Electrophotography (AREA)
Abstract
Description
【０００１】0001
【産業上の利用分野】本発明は静電荷現像用トナーに関
し、特に低現像電位のシステムに使用される静電荷現像
用トナーに関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to toners for electrostatic charge development, and more particularly to toners for electrostatic charge development used in low development potential systems.
【０００２】0002
【従来の技術】一般に電子写真法は感光体上に電気的な
潜像を形成し、ついで該潜像をトナーによって現像し、
必要に応じて紙などの転写材にトナー画像を転写した後
、加熱・加圧などの手段によって定着し被写物を得るも
のである。このような電子写真法に用いられる現像剤と
しては、トナーとキャリアからなる二成分現像剤とトナ
ーとキャリアの機能を同時に備えた一成分現像剤とがあ
る。2. Description of the Related Art Generally, in electrophotography, an electrical latent image is formed on a photoreceptor, and then the latent image is developed with toner.
After a toner image is transferred to a transfer material such as paper as necessary, it is fixed by means such as heating and pressure to obtain an object. Developers used in such electrophotography include two-component developers consisting of toner and carrier, and one-component developers having the functions of toner and carrier at the same time.
【０００３】一成分現像剤には磁性一成分現像剤と非磁
性一成分現像剤があり、このうち磁性一成分現像剤とし
ては磁性粉を１０〜７０重量％程度含有した磁性トナー
が用いられる。また、磁性トナーは導電性磁性トナーと
絶縁性磁性トナーに分類され、前者は静電誘導あるいは
電荷注入が現像駆動力となり、後者は摩擦帯電による電
荷が現像駆動力となる。[0003] One-component developers include magnetic one-component developers and non-magnetic one-component developers, and among these, magnetic toner containing about 10 to 70% by weight of magnetic powder is used as the magnetic one-component developer. Further, magnetic toner is classified into conductive magnetic toner and insulating magnetic toner, and for the former, electrostatic induction or charge injection is the development driving force, while for the latter, the development driving force is electric charge due to triboelectric charging.
【０００４】導電性磁性トナーを用いた一成分現像方式
では、導電性磁性トナー自体が現像電極となるため、エ
ッジ効果のない均一な画像が得られるという利点がある
ことが知られている。また、トナーの体積固有抵抗率を
およそ１×１０４ Ω・ｃｍ以下に抑えることによって
現像電位が１００Ｖ以下の低電位現像システムにも利用
できるという利点が生じる。It is known that the one-component development method using conductive magnetic toner has the advantage that a uniform image without edge effects can be obtained because the conductive magnetic toner itself serves as a developing electrode. Further, by suppressing the specific volume resistivity of the toner to approximately 1×10 4 Ω·cm or less, there is an advantage that it can be used in a low-potential development system with a development potential of 100 V or less.
【０００５】しかし、導電性磁性トナーは静電転写時に
転写紙を介してトナーの電荷がリークしやすく、普通紙
への転写が困難であるという欠点がある。また、感光体
上にトナー粒子が１層しか現像されないため、画像濃度
の確保が困難であるという欠点もある。However, conductive magnetic toner has the disadvantage that the charge of the toner tends to leak through the transfer paper during electrostatic transfer, making it difficult to transfer to plain paper. Further, since only one layer of toner particles is developed on the photoreceptor, there is also the drawback that it is difficult to ensure image density.
【０００６】この中で転写性の問題については高抵抗処
理を施した特殊紙を用いたり、ゴムローラによる圧力転
写方式を採用したりすることによってある程度解決され
るが、画像濃度の確保は本質的な問題であり、従来技術
ではいまだ満足される状況にない。Among these problems, the problem of transferability can be solved to some extent by using special paper treated with high resistance or by adopting a pressure transfer method using rubber rollers, but ensuring image density is essential. This is a problem that has not yet been satisfactorily achieved using conventional techniques.
【０００７】[0007]
【発明が解決しようとする課題】本発明は上記の従来の
技術における問題点を解決し、低電位現像システムにお
いて十分な画像濃度を得、かつカブリのない良好な画像
特性を得ることができる静電荷現像用トナーを提供する
ことを目的とするものである。SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems in the conventional technology, and provides a static image forming system that can obtain sufficient image density and good image characteristics without fog in a low-potential development system. The object of the present invention is to provide a toner for charge development.
【０００８】[0008]
【課題を解決するための手段】本発明は、前記の課題を
解決するためになされたもので、磁性粉を３０〜７０重
量％含有し体積固有抵抗率が１×１０３ Ω・ｃｍ以下
である導電性磁性トナーと、体積固有抵抗率が１×１０
９ Ω・ｃｍ以上で、真円度が０．５以上である絶縁性
非磁性トナーとを、重量比で６０：４０〜９０：１０の
割合で混合してなることを特徴とする静電荷現像用トナ
ーである。[Means for Solving the Problems] The present invention has been made to solve the above-mentioned problems, and contains 30 to 70% by weight of magnetic powder and has a volume resistivity of 1 x 103 Ωcm or less. Conductive magnetic toner and volume resistivity of 1×10
An electrostatic charge developer characterized by being mixed with an insulating non-magnetic toner having a resistance of 9 Ω·cm or more and a roundness of 0.5 or more in a weight ratio of 60:40 to 90:10. It is a toner for use.
【０００９】導電性磁性トナーの体積固有抵抗率は、主
電極面積が１．００ｃｍ２ の円筒型電極に試料を入れ
て２００ｇ／ｃｍ２ の荷重をかけ、１００Ｖ／ｃｍの
電界下で測定された値である。The specific volume resistivity of conductive magnetic toner is a value measured under an electric field of 100 V/cm by placing a sample in a cylindrical electrode with a main electrode area of 1.00 cm2 and applying a load of 200 g/cm2. be.
【００１０】絶縁性非磁性トナーの体積固有抵抗率は導
電性磁性トナーのそれとはかなり異なるため、同様の測
定方法では測定できない。したがって、本発明の絶縁性
非磁性トナーの体積固有抵抗率は、絶縁性非磁性トナー
を２００ｋｇ／ｃｍ２ の圧力下で成型し、ＳＥ−７０
型固体電極（安藤電気社製）にセットした後、２５００
Ａキャパシタンスブリッジ（東陽テクニカ社製）で測定
した値である。The specific volume resistivity of an insulating non-magnetic toner is quite different from that of a conductive magnetic toner, so it cannot be measured using a similar measuring method. Therefore, the specific volume resistivity of the insulating non-magnetic toner of the present invention is determined by molding the insulating non-magnetic toner under a pressure of 200 kg/cm2,
After setting it on a type solid electrode (manufactured by Ando Electric Co., Ltd.),
This is a value measured with an A capacitance bridge (manufactured by Toyo Technica).
【００１１】絶縁性非磁性トナー粒子の真円度は、以下
のようにして測定する。まず、ＳＥＭ（走査型電子顕微
鏡）でトナー像を撮影し、その画像を画像処理装置に入
力して以下の式から求める。
真円度＝（４π×面積）／（周囲の長さ）２ 真円度は
物体が真円の場合に最大１となり、不定形の場合は０に
近くなる。The circularity of the insulating nonmagnetic toner particles is measured as follows. First, a toner image is photographed using a SEM (scanning electron microscope), the image is input to an image processing device, and the image is calculated using the following formula. Circularity = (4π x area) / (perimeter length) 2 The circularity is at most 1 when the object is a perfect circle, and close to 0 when the object is amorphous.
【００１２】本発明における導電性磁性トナーは磁性粉
及びカーボンブラックを結着樹脂中に分散し機械的に粉
砕した後、体積平均粒子径７〜１０μｍ程度に分級して
得られる。また、分級後にトナー表面の導電性を均一化
するためにカーボンブラックなどの導電性材料を、また
流動性向上のためにシリカなどの添加剤を各々トナー粒
子表面に付着させてもよい。The conductive magnetic toner of the present invention is obtained by dispersing magnetic powder and carbon black in a binder resin, mechanically pulverizing the resulting particles, and then classifying the particles to have a volume average particle diameter of about 7 to 10 μm. Further, after classification, a conductive material such as carbon black may be attached to the surface of the toner particles to make the conductivity of the toner surface uniform, and an additive such as silica may be attached to the surface of the toner particle to improve fluidity.
【００１３】本発明において、導電性磁性トナーに使用
される結着樹脂はポリスチレン、ポリエチレン、ポリプ
ロピレン、ビニル系樹脂、ポリアクリレート、ポリメタ
クリレート、ポリ塩化ビニリデン、ポリアクリロニトリ
ル、ポリエーテル、ポリカーボネート、熱可塑性ポリエ
ステル、熱可塑性エポキシ樹脂、セルロース系樹脂及び
それらのモノマーの共重合樹脂などの熱可塑性樹脂の他
、変性アクリル樹脂、フェノール樹脂、メラミン樹脂、
ユリア樹脂などの熱硬化性樹脂を使用することができる
。また磁性粉としては結晶学的にスピネル、ペロブスカ
イト、六方晶、ガーネット、オルソフェライト構造を有
するフェライトやマグネタイトなどが適用される。
フェライトの構成はニッケル、亜鉛、マンガン、マグネ
シウム、銅、リチウム、バリウム、バナジウム、クロム
、カルシウムなどの酸化物と３価の鉄酸化物との焼結体
である。In the present invention, the binder resin used in the conductive magnetic toner is polystyrene, polyethylene, polypropylene, vinyl resin, polyacrylate, polymethacrylate, polyvinylidene chloride, polyacrylonitrile, polyether, polycarbonate, thermoplastic polyester. In addition to thermoplastic resins such as thermoplastic epoxy resins, cellulose resins, and copolymer resins of these monomers, modified acrylic resins, phenolic resins, melamine resins,
Thermosetting resins such as urea resins can be used. Further, as the magnetic powder, ferrite or magnetite having a crystallographic structure of spinel, perovskite, hexagonal crystal, garnet, orthoferrite is used. Ferrite is a sintered body of oxides of nickel, zinc, manganese, magnesium, copper, lithium, barium, vanadium, chromium, calcium, etc., and trivalent iron oxide.
【００１４】本発明において、絶縁性非磁性トナーも同
様にカーボンブラックなどの着色剤や帯電量調整剤を結
着樹脂中に分散させ、粉砕・分級した後熱気流中で球形
化処理を行ったり、高速気流中で衝撃力を加えたりして
、真円度が０．５以上になるように調整する。また、ト
ナー材料を溶剤に分散させ、スプレードライすることに
よっても所望の絶縁性非磁性トナーを得ることができる
。さらに、結着樹脂重合時にカーボンブラックや帯電量
調整剤を分散し、直接所望の粒子径の絶縁性非磁性トナ
ーを作成してもよい。重合方法としては懸濁重合法や乳
化重合法等が好適に使用することができる。このように
して得られた絶縁性非磁性トナーの表面には流動性向上
のためにシリカなどの添加剤を付着させてもよい。In the present invention, the insulating non-magnetic toner is also prepared by dispersing a coloring agent such as carbon black and a charge control agent in a binder resin, pulverizing and classifying the toner, and then subjecting the toner to spheroidization in a hot air stream. Adjust the roundness to 0.5 or more by applying an impact force in a high-speed airflow. Alternatively, the desired insulating nonmagnetic toner can be obtained by dispersing the toner material in a solvent and spray drying it. Furthermore, an insulating non-magnetic toner having a desired particle size may be directly produced by dispersing carbon black or a charge control agent during polymerization of the binder resin. As the polymerization method, suspension polymerization method, emulsion polymerization method, etc. can be suitably used. An additive such as silica may be attached to the surface of the insulating nonmagnetic toner thus obtained to improve fluidity.
【００１５】本発明において、絶縁性磁性トナーに使用
される結着樹脂には前述の導電性磁性トナーに例示した
ものが適宜使用される。また、必要に応じてモノアゾ系
の金属染料やニグロシン系の染料、第４級アンモニウム
塩などの帯電量調整剤を使用してもよい。In the present invention, the binder resin used in the insulating magnetic toner includes those exemplified for the conductive magnetic toner described above. Further, if necessary, a charge control agent such as a monoazo metal dye, a nigrosine dye, or a quaternary ammonium salt may be used.
【００１６】[0016]
【作用】本発明の静電荷現像用トナーを構成する導電性
磁性トナーは、現像電解下で電荷が静電誘導あるいは現
像スリーブより注入され、感光体上の画像潜像部と導電
性磁性トナーとの静電引力が磁気束縛力より大きくなる
と画像潜像部に付着し現像される。一方、絶縁性非磁性
トナーは現像噐の穂高規制ブレードや導電性磁性トナー
等との間の摩擦帯電によって絶縁性非磁性トナーに電荷
が生じ画像潜像部に現像される。したがって、感光体上
の画像潜像部には多くの導電性磁性トナーと絶縁性非磁
性トナーとが混在して付着するため十分な画像濃度を得
ることができる。[Function] The conductive magnetic toner constituting the electrostatic charge developing toner of the present invention is electrostatically injected with electric charge through electrostatic induction or a developing sleeve, and the conductive magnetic toner is transferred between the latent image area on the photoreceptor and the conductive magnetic toner. When the electrostatic attractive force becomes larger than the magnetic binding force, it adheres to the latent image area and is developed. On the other hand, the insulating non-magnetic toner is charged by friction between it and the height regulating blade of the developer, the conductive magnetic toner, etc., and is developed in the latent image area. Therefore, a large amount of conductive magnetic toner and insulating non-magnetic toner adhere to the latent image area on the photoreceptor in a mixed manner, so that sufficient image density can be obtained.
【００１７】本発明の静電荷現像用トナーは現像器内で
混合攪拌され、マグネットローラーによって現像スリー
静電荷現像用トナーは現像器内で混合攪拌されマグネッ
トローラーによって現像スリーブ上に導電性磁性トナー
の穂が形成される。このため導電性磁性トナーに含有さ
れる磁性粉は３０〜７０重量％であることが必要である
。３０重量％未満では静電荷現像用トナーの磁力が小さ
くなるため搬送性が不良となる。また、７０重量％を越
えて多い場合は、磁性粉を結着樹脂中に分散させるのが
困難になるだけでなく、カーボンブラック等の導電性材
料の配合量が少なくなるために導電性の確保が困難とな
る。絶縁性非磁性トナーは摩擦帯電による静電気力によ
って導電性磁性トナーに付着し、導電性磁性トナーと同
様に画像潜像部に搬送される。導電性磁性トナーと絶縁
性非磁性トナーの混合比率は６０：４０〜９０：１０が
良好に使用し得る。絶縁性非磁性トナーの比率が４０を
越えて多い（導電性磁性トナーの比率が６０未満）場合
は、導電性磁性トナーによる搬送性が悪くなり、トナー
落ちやトナー飛散などの問題が発生しやすい。また、絶
縁性非磁性トナーの比率が１０未満（導電性磁性トナー
の比率が９０を越えて多い）の場合は、十分な画像濃度
を得ることができなくなる。The toner for electrostatic charge development of the present invention is mixed and agitated in a developing device, and developed by a magnetic roller. Ears are formed. Therefore, it is necessary that the magnetic powder contained in the conductive magnetic toner be 30 to 70% by weight. If it is less than 30% by weight, the magnetic force of the electrostatic charge developing toner becomes small, resulting in poor conveyance. In addition, if the amount exceeds 70% by weight, not only will it be difficult to disperse the magnetic powder in the binder resin, but the amount of conductive material such as carbon black will be reduced, making it difficult to ensure conductivity. becomes difficult. The insulating non-magnetic toner adheres to the conductive magnetic toner by electrostatic force caused by frictional charging, and is conveyed to the latent image area in the same manner as the conductive magnetic toner. A suitable mixing ratio of the conductive magnetic toner and the insulating non-magnetic toner is 60:40 to 90:10. If the ratio of insulating non-magnetic toner is more than 40 (the ratio of conductive magnetic toner is less than 60), the transportability of the conductive magnetic toner will be poor, and problems such as toner dropping and toner scattering will likely occur. . Furthermore, if the ratio of insulating non-magnetic toner is less than 10 (the ratio of conductive magnetic toner is more than 90), sufficient image density cannot be obtained.
【００１８】導電性磁性トナーの体積固有抵抗率が１×
１０３ Ω・ｃｍを越えて大きい場合は、静電荷現像用
トナーとしての体積固有抵抗率が高くなってしまい、低
電位での現像が困難になる。また、絶縁性非磁性トナー
の体積固有抵抗率が１×１０９Ω・ｃｍ未満の場合には
電荷の漏洩によって十分な摩擦帯電量を得ることができ
なくなり、結果として画像濃度が低くなる。The volume resistivity of the conductive magnetic toner is 1×
If it exceeds 10 3 Ω·cm, the specific volume resistivity of the toner for electrostatic charge development becomes high, making it difficult to develop at a low potential. Furthermore, if the specific volume resistivity of the insulating nonmagnetic toner is less than 1×10 9 Ω·cm, a sufficient amount of triboelectric charge cannot be obtained due to charge leakage, resulting in a low image density.
【００１９】本発明の静電荷現像用トナーを現像器内で
攪拌すると、導電性磁性トナー表面に露出もしくは付着
しているカーボンブラックの一部が絶縁性非磁性トナー
表面に移行する。このため導電性磁性トナーへの電荷注
入が不良となり、カブリなどの画像不良が発生する。本
発明では絶縁性非磁性トナーの真円度を０．５以上とし
、表面積を極小にすることによって導電性磁性トナー表
面からのカーボンブラックの移行量を制限し、画像不良
の発生を予防するものである。When the electrostatic charge developing toner of the present invention is stirred in a developing device, a portion of the carbon black exposed or attached to the surface of the conductive magnetic toner is transferred to the surface of the insulating non-magnetic toner. As a result, charge injection into the conductive magnetic toner becomes defective, resulting in image defects such as fog. In the present invention, the roundness of the insulating non-magnetic toner is set to 0.5 or more, and the surface area is minimized to limit the amount of carbon black transferred from the surface of the conductive magnetic toner, thereby preventing the occurrence of image defects. It is.
【００２０】[0020]
【実施例】以下本発明の実施例について説明する。なお
「部」とは重量部を表わす。
実施例１
上記配合の材料を２本ロールの混練機で溶融混練を
行いジェットミルで粉砕をして分級し、体積平均粒子径
９μｍの導電性磁性トナーを得た。この導電性磁性トナ
ーの体積固有抵抗率は５×１０２ Ω・ｃｍであった。
さらに、
上記配合の材料を２本ロールの混練機で溶融混練を
行いジェットミルで粉砕をして分級した後、ナラ・ハイ
ブリダイゼーション・システムにより高速気流中で衝撃
力を加えて体積平均粒子径９μｍのトナー粒子を得た。
さらにこのトナー粒子１００部に対し０．２部の疎水性
シリカ（Ｒー９７２：日本アエロジル社製）を混合して
絶縁性非磁性トナーを得た。この絶縁性非磁性トナーの
体積固有抵抗率は７×１０１０Ω・ｃｍであり、真円度
は０．５８であった。上記導電性磁性トナーと絶縁性非
磁性トナーを７０：３０重量部の割合で混合して本発明
の静電荷現像用トナーを得た。[Examples] Examples of the present invention will be described below. Note that "parts" represent parts by weight. Example 1 The above-mentioned materials were melt-kneaded using a two-roll kneader, pulverized using a jet mill, and classified to obtain a conductive magnetic toner having a volume average particle diameter of 9 μm. The volume specific resistivity of this conductive magnetic toner was 5×10 2 Ω·cm. Furthermore, the above-mentioned blended materials were melt-kneaded using a two-roll kneader, pulverized and classified using a jet mill, and then subjected to impact force in a high-speed air stream using the Nara Hybridization System to obtain a volume-average particle size of 9 μm. toner particles were obtained. Further, 0.2 parts of hydrophobic silica (R-972, manufactured by Nippon Aerosil Co., Ltd.) was mixed with 100 parts of the toner particles to obtain an insulating nonmagnetic toner. The volume specific resistivity of this insulating nonmagnetic toner was 7×10 10 Ω·cm, and the circularity was 0.58. The above conductive magnetic toner and insulating non-magnetic toner were mixed in a ratio of 70:30 parts by weight to obtain a toner for electrostatic charge development of the present invention.
【００２１】実施例２
上記配合の材料をよく分散させた後懸濁重合を行い
、脱水、洗浄、乾燥して体積平均粒子径９μｍのトナー
粒子を得た。さらにこのトナー粒子１００部に対して０
．２部の疎水性シリカ（Ｒー９７２：日本アエロジル社
製）を混合して絶縁性非磁性トナーを得た。この絶縁性
非磁性トナーの体積固有抵抗率は３×１０１０Ω・ｃｍ
であり、真円度は０．７８であった。実施例１の導電性
磁性トナーと実施例２の絶縁性非磁性トナーを重量比で
７０：３０の割合で混合して本発明の静電荷現像用トナ
ーを得た。Example 2 The above-mentioned materials were well dispersed and then subjected to suspension polymerization, followed by dehydration, washing and drying to obtain toner particles having a volume average particle diameter of 9 μm. Furthermore, 0 parts per 100 parts of this toner particle.
．． Two parts of hydrophobic silica (R-972: manufactured by Nippon Aerosil Co., Ltd.) were mixed to obtain an insulating nonmagnetic toner. The specific volume resistivity of this insulating non-magnetic toner is 3×1010Ω・cm
The roundness was 0.78. The conductive magnetic toner of Example 1 and the insulating non-magnetic toner of Example 2 were mixed at a weight ratio of 70:30 to obtain an electrostatic charge developing toner of the present invention.
【００２２】比較例１
上記配合の材料を２本ロールの混練機で溶融混練を行い
ジェットミルで粉砕して分級し、体積平均粒子径９μｍ
の導電性磁性トナーを得た。この導電性磁性トナーの体
積固有抵抗率は６×１０４ Ω・ｃｍであった。上記導
電性磁性トナーと実施例１の絶縁性非磁性トナーを７０
：３０重量部の割合で混合して比較例１の静電荷現像用
トナーを得た。Comparative Example 1 The above-mentioned blended materials were melt-kneaded in a two-roll kneader, pulverized and classified in a jet mill, and the volume average particle diameter was 9 μm.
A conductive magnetic toner was obtained. The volume specific resistivity of this conductive magnetic toner was 6×10 4 Ω·cm. 70% of the above conductive magnetic toner and the insulating non-magnetic toner of Example 1.
: 30 parts by weight to obtain an electrostatic charge developing toner of Comparative Example 1.
【００２３】比較例２
上記配合の材料をよく分散させた後懸濁重合を行い
、脱水、洗浄、乾燥して体積平均粒子径９μｍのトナー
粒子を得た。さらにこのトナー粒子１００部に対して０
．２部の疎水性シリカ（Ｒー９７２：日本アエロジル社
製）を混合して絶縁性非磁性トナーを得た。この絶縁性
非磁性トナーの体積固有抵抗率は６×１０８ Ω・ｃｍ
であり、真円度は０．７５であった。実施例１の導電性
磁性トナーと上記の絶縁性非磁性トナーを重量比で７０
：３０の割合で混合して比較例２の静電荷現像用トナー
を得た。Comparative Example 2 The above-mentioned ingredients were well dispersed and then subjected to suspension polymerization, followed by dehydration, washing and drying to obtain toner particles having a volume average particle diameter of 9 μm. Furthermore, 0 parts per 100 parts of this toner particle.
．． Two parts of hydrophobic silica (R-972: manufactured by Nippon Aerosil Co., Ltd.) were mixed to obtain an insulating nonmagnetic toner. The specific volume resistivity of this insulating non-magnetic toner is 6×108 Ω・cm
The roundness was 0.75. The weight ratio of the conductive magnetic toner of Example 1 and the above insulating non-magnetic toner was 70.
:30 to obtain an electrostatic charge developing toner of Comparative Example 2.
【００２４】比較例３
実施例１の絶縁性非磁性トナーにおいて、気流中での衝
撃力を加えずに体積平均粒子径９μｍの絶縁性非磁性ト
ナーを得た。この絶縁性非磁性トナーの体積固有抵抗率
は７．２×１０１０Ω・ｃｍであり、真円度は０．４２
であつた。さらに、実施例１の導電性磁性トナーと上記
絶縁性非磁性トナーを７０：３０重量部の割合で混合し
て比較例３の静電荷現像用トナーを得た。Comparative Example 3 An insulating non-magnetic toner having a volume average particle diameter of 9 μm was obtained using the insulating non-magnetic toner of Example 1 without applying impact force in an air stream. The volume specific resistivity of this insulating non-magnetic toner is 7.2 x 1010 Ωcm, and the circularity is 0.42.
It was hot. Further, the electroconductive magnetic toner of Example 1 and the insulating non-magnetic toner were mixed in a ratio of 70:30 parts by weight to obtain a toner for electrostatic charge development of Comparative Example 3.
【００２５】比較例４
実施例１の導電性磁性トナーのみで比較例４の静電荷現
像用トナーを得た。Comparative Example 4 An electrostatic charge developing toner of Comparative Example 4 was obtained using only the conductive magnetic toner of Example 1.
【００２６】比較例５
実施例１の導電性磁性トナーと実施例１の絶縁性非磁性
トナーとを重量比で５０：５０の割合で混合して比較例
５の静電荷現像用トナーを得た。Comparative Example 5 The conductive magnetic toner of Example 1 and the insulating non-magnetic toner of Example 1 were mixed at a weight ratio of 50:50 to obtain an electrostatic charge developing toner of Comparative Example 5. .
【００２７】以上の実施例１〜２及び比較例１〜５の静
電荷現像用トナーを現像電位が４０ＶであるＬＥＤ反転
プリンタに適用して試験したところ、表１の結果を得た
。When the electrostatic charge developing toners of Examples 1 to 2 and Comparative Examples 1 to 5 were applied to an LED reversing printer with a developing potential of 40 V and tested, the results shown in Table 1 were obtained.
【００２８】[0028]
【表１】[Table 1]
【００２９】表１の画像濃度はマクベスＲＤ９１４反射
濃度計で測定した値である。また、カブリ値はＲＥＦＬ
ＥＣＴＯＭＥＴＥＲ ＴＣ−６Ｄ（東京電色社製）で
測定した値である。表１から明らかなように本発明の静
電荷現像用トナーは画像濃度及び画像の解像度も良好で
あって、カブリも極めて少ないものであった。これに対
して、比較例１、比較例２及び比較例４は画像濃度が低
く、比較例２、比較例３及び比較例５についてはカブリ
が多く実用上支障をきたすことが確認された。The image densities in Table 1 are values measured with a Macbeth RD914 reflection densitometer. Also, the fog value is REFL
This is a value measured with ECTOMETER TC-6D (manufactured by Tokyo Denshokusha). As is clear from Table 1, the toner for electrostatic charge development of the present invention had good image density and image resolution, and had very little fog. On the other hand, it was confirmed that Comparative Example 1, Comparative Example 2, and Comparative Example 4 had low image density, and Comparative Example 2, Comparative Example 3, and Comparative Example 5 had a lot of fog, which caused problems in practical use.
【００３０】[0030]
【発明の効果】本発明は低電位現像システムにおいて十
分な画像濃度を得、かつカブリがなく良好な画像を得る
ことができる静電荷現像用トナーを提供することができ
る。Effects of the Invention The present invention can provide a toner for electrostatic charge development which can obtain sufficient image density in a low potential development system and can provide good images without fogging.
Claims (1)
る体積固有抵抗率が１×１０３ Ω・ｃｍ以下である導
電性磁性トナーと、体積固有抵抗率が１×１０９Ω・ｃ
ｍ以上、真円度が０．５以上である絶縁性非磁性トナー
とを、重量比で６０：４０〜９０：１０の割合で混合し
てなることを特徴とする静電荷現像用トナー。1. A conductive magnetic toner containing 30 to 70% by weight of magnetic powder and having a volume resistivity of 1×10 3 Ω·cm or less, and a volume resistivity of 1 × 10 9 Ω·c.
m or more and an insulating non-magnetic toner having a roundness of 0.5 or more in a weight ratio of 60:40 to 90:10.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3084589A JP2567748B2 (en) | 1991-03-26 | 1991-03-26 | Toner for electrostatic charge development |
| US07/856,717 US5258254A (en) | 1991-03-26 | 1992-03-24 | Toner for developing static charge images |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3084589A JP2567748B2 (en) | 1991-03-26 | 1991-03-26 | Toner for electrostatic charge development |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04296765A true JPH04296765A (en) | 1992-10-21 |
| JP2567748B2 JP2567748B2 (en) | 1996-12-25 |
Family
ID=13834864
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3084589A Expired - Lifetime JP2567748B2 (en) | 1991-03-26 | 1991-03-26 | Toner for electrostatic charge development |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2567748B2 (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56159653A (en) * | 1980-05-13 | 1981-12-09 | Ricoh Co Ltd | Developer for electrostatic latent image |
| JPS6053960A (en) * | 1983-09-03 | 1985-03-28 | Canon Inc | Formation of image |
| JPS61149968A (en) * | 1984-12-25 | 1986-07-08 | Fujitsu Ltd | Electrostatic recording device |
| JPS63135969A (en) * | 1986-11-27 | 1988-06-08 | Seiko Epson Corp | Printing method |
| JPS63214781A (en) * | 1987-03-04 | 1988-09-07 | Fujitsu Ltd | Image forming device |
-
1991
- 1991-03-26 JP JP3084589A patent/JP2567748B2/en not_active Expired - Lifetime
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56159653A (en) * | 1980-05-13 | 1981-12-09 | Ricoh Co Ltd | Developer for electrostatic latent image |
| JPS6053960A (en) * | 1983-09-03 | 1985-03-28 | Canon Inc | Formation of image |
| JPS61149968A (en) * | 1984-12-25 | 1986-07-08 | Fujitsu Ltd | Electrostatic recording device |
| JPS63135969A (en) * | 1986-11-27 | 1988-06-08 | Seiko Epson Corp | Printing method |
| JPS63214781A (en) * | 1987-03-04 | 1988-09-07 | Fujitsu Ltd | Image forming device |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2567748B2 (en) | 1996-12-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3120460B2 (en) | Electrophotographic developer | |
| US4448870A (en) | Magnetic color toner | |
| US5374978A (en) | Developing method | |
| JPS61180247A (en) | Developer for electrostatic latent image | |
| JP2853174B2 (en) | Developing device | |
| US4277552A (en) | Magnetic developing process and toner containing high coercive force magnetic powder | |
| JPH027062B2 (en) | ||
| JP2754600B2 (en) | Electrophotographic color toner | |
| JP2567748B2 (en) | Toner for electrostatic charge development | |
| JP2887717B2 (en) | Electrostatic toner | |
| US5532095A (en) | Magnetic toner | |
| JPS638750A (en) | Magnetic toner | |
| US5258254A (en) | Toner for developing static charge images | |
| JP3010917B2 (en) | Method for developing one-component insulating magnetic toner | |
| JP2887713B2 (en) | Electrostatic toner | |
| JP2962040B2 (en) | Method for developing one-component insulating magnetic toner | |
| JP2510156B2 (en) | Reverse development method | |
| JPH0119580B2 (en) | ||
| JP2581631B2 (en) | Electrostatic toner | |
| JP2686481B2 (en) | Toner for electrostatic charge development | |
| JP2533007B2 (en) | Toner for electrostatic charge development | |
| JPH04296764A (en) | Toner for developing electrostatic charge image | |
| JP2870556B2 (en) | Image recording method | |
| JP3249924B2 (en) | Image forming method and magnetic toner used therefor | |
| JP2686480B2 (en) | Toner for electrostatic charge development |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 19960723 |