JPH0629992B2 - Two-component developer for electrophotography - Google Patents
Two-component developer for electrophotographyInfo
- Publication number
- JPH0629992B2 JPH0629992B2 JP59084000A JP8400084A JPH0629992B2 JP H0629992 B2 JPH0629992 B2 JP H0629992B2 JP 59084000 A JP59084000 A JP 59084000A JP 8400084 A JP8400084 A JP 8400084A JP H0629992 B2 JPH0629992 B2 JP H0629992B2
- Authority
- JP
- Japan
- Prior art keywords
- toner
- carrier
- ferrite
- resistance
- image
- 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
- 229910000859 α-Fe Inorganic materials 0.000 claims description 56
- 239000002245 particle Substances 0.000 claims description 42
- 229910021417 amorphous silicon Inorganic materials 0.000 description 17
- 238000011161 development Methods 0.000 description 15
- 238000012546 transfer Methods 0.000 description 13
- 239000008186 active pharmaceutical agent Substances 0.000 description 11
- 239000000969 carrier Substances 0.000 description 10
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 9
- 230000007246 mechanism Effects 0.000 description 8
- 239000000203 mixture Substances 0.000 description 8
- 230000008901 benefit Effects 0.000 description 7
- 229910052739 hydrogen Inorganic materials 0.000 description 7
- 239000001257 hydrogen Substances 0.000 description 7
- 238000000034 method Methods 0.000 description 7
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 6
- 229920005989 resin Polymers 0.000 description 6
- 239000011347 resin Substances 0.000 description 6
- 238000004140 cleaning Methods 0.000 description 5
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- BUGBHKTXTAQXES-UHFFFAOYSA-N Selenium Chemical compound [Se] BUGBHKTXTAQXES-UHFFFAOYSA-N 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- 229910052711 selenium Inorganic materials 0.000 description 4
- 239000011669 selenium Substances 0.000 description 4
- 229910017518 Cu Zn Inorganic materials 0.000 description 3
- 229910017752 Cu-Zn Inorganic materials 0.000 description 3
- 229910017943 Cu—Zn Inorganic materials 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 230000003287 optical effect Effects 0.000 description 3
- 108091008695 photoreceptors Proteins 0.000 description 3
- 230000009467 reduction Effects 0.000 description 3
- 230000035945 sensitivity Effects 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 229910001035 Soft ferrite Inorganic materials 0.000 description 2
- PPBRXRYQALVLMV-UHFFFAOYSA-N Styrene Chemical compound C=CC1=CC=CC=C1 PPBRXRYQALVLMV-UHFFFAOYSA-N 0.000 description 2
- 238000005452 bending Methods 0.000 description 2
- 239000006229 carbon black Substances 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- TVZPLCNGKSPOJA-UHFFFAOYSA-N copper zinc Chemical compound [Cu].[Zn] TVZPLCNGKSPOJA-UHFFFAOYSA-N 0.000 description 2
- 238000005520 cutting process Methods 0.000 description 2
- 238000000354 decomposition reaction Methods 0.000 description 2
- 230000006866 deterioration Effects 0.000 description 2
- 239000000975 dye Substances 0.000 description 2
- ZZUFCTLCJUWOSV-UHFFFAOYSA-N furosemide Chemical compound C1=C(Cl)C(S(=O)(=O)N)=CC(C(O)=O)=C1NCC1=CC=CO1 ZZUFCTLCJUWOSV-UHFFFAOYSA-N 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- 230000005415 magnetization Effects 0.000 description 2
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- 230000003068 static effect Effects 0.000 description 2
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- 238000012360 testing method Methods 0.000 description 2
- 229920002554 vinyl polymer Polymers 0.000 description 2
- RSWGJHLUYNHPMX-UHFFFAOYSA-N 1,4a-dimethyl-7-propan-2-yl-2,3,4,4b,5,6,10,10a-octahydrophenanthrene-1-carboxylic acid Chemical compound C12CCC(C(C)C)=CC2=CCC2C1(C)CCCC2(C)C(O)=O RSWGJHLUYNHPMX-UHFFFAOYSA-N 0.000 description 1
- AQSOTOUQTVJNMY-UHFFFAOYSA-N 7-(dimethylamino)-4-hydroxy-3-oxophenoxazin-10-ium-1-carboxylic acid;chloride Chemical compound [Cl-].OC(=O)C1=CC(=O)C(O)=C2OC3=CC(N(C)C)=CC=C3[NH+]=C21 AQSOTOUQTVJNMY-UHFFFAOYSA-N 0.000 description 1
- 239000004925 Acrylic resin Substances 0.000 description 1
- 229920000178 Acrylic resin Polymers 0.000 description 1
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- 229910018605 Ni—Zn Inorganic materials 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- 239000004743 Polypropylene Substances 0.000 description 1
- 239000004793 Polystyrene Substances 0.000 description 1
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical group [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 description 1
- 241000519995 Stachys sylvatica Species 0.000 description 1
- AUNAPVYQLLNFOI-UHFFFAOYSA-L [Pb++].[Pb++].[Pb++].[O-]S([O-])(=O)=O.[O-][Cr]([O-])(=O)=O.[O-][Mo]([O-])(=O)=O Chemical compound [Pb++].[Pb++].[Pb++].[O-]S([O-])(=O)=O.[O-][Cr]([O-])(=O)=O.[O-][Mo]([O-])(=O)=O AUNAPVYQLLNFOI-UHFFFAOYSA-L 0.000 description 1
- 239000011354 acetal resin Substances 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 238000005273 aeration Methods 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 239000012298 atmosphere Substances 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 229910052796 boron Inorganic materials 0.000 description 1
- CJOBVZJTOIVNNF-UHFFFAOYSA-N cadmium sulfide Chemical compound [Cd]=S CJOBVZJTOIVNNF-UHFFFAOYSA-N 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- JBTHDAVBDKKSRW-UHFFFAOYSA-N chembl1552233 Chemical compound CC1=CC(C)=CC=C1N=NC1=C(O)C=CC2=CC=CC=C12 JBTHDAVBDKKSRW-UHFFFAOYSA-N 0.000 description 1
- 238000004040 coloring Methods 0.000 description 1
- 239000007859 condensation product Substances 0.000 description 1
- XCJYREBRNVKWGJ-UHFFFAOYSA-N copper(II) phthalocyanine Chemical compound [Cu+2].C12=CC=CC=C2C(N=C2[N-]C(C3=CC=CC=C32)=N2)=NC1=NC([C]1C=CC=CC1=1)=NC=1N=C1[C]3C=CC=CC3=C2[N-]1 XCJYREBRNVKWGJ-UHFFFAOYSA-N 0.000 description 1
- 229910021419 crystalline silicon Inorganic materials 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 235000014113 dietary fatty acids Nutrition 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 210000005069 ears Anatomy 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000003822 epoxy resin Substances 0.000 description 1
- PLYDMIIYRWUYBP-UHFFFAOYSA-N ethyl 4-[[2-chloro-4-[3-chloro-4-[(3-ethoxycarbonyl-5-oxo-1-phenyl-4h-pyrazol-4-yl)diazenyl]phenyl]phenyl]diazenyl]-5-oxo-1-phenyl-4h-pyrazole-3-carboxylate Chemical compound CCOC(=O)C1=NN(C=2C=CC=CC=2)C(=O)C1N=NC(C(=C1)Cl)=CC=C1C(C=C1Cl)=CC=C1N=NC(C(=N1)C(=O)OCC)C(=O)N1C1=CC=CC=C1 PLYDMIIYRWUYBP-UHFFFAOYSA-N 0.000 description 1
- 229930195729 fatty acid Natural products 0.000 description 1
- 239000000194 fatty acid Substances 0.000 description 1
- 150000004665 fatty acids Chemical class 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 229910021478 group 5 element Inorganic materials 0.000 description 1
- 229910052736 halogen Inorganic materials 0.000 description 1
- 150000002367 halogens Chemical class 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
- 150000002431 hydrogen Chemical class 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 125000005609 naphthenate group Chemical group 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 229920001568 phenolic resin Polymers 0.000 description 1
- 239000005011 phenolic resin Substances 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 229920000647 polyepoxide Polymers 0.000 description 1
- 229920001225 polyester resin Polymers 0.000 description 1
- 239000004645 polyester resin Substances 0.000 description 1
- 229920005672 polyolefin resin Polymers 0.000 description 1
- 229920006324 polyoxymethylene Polymers 0.000 description 1
- -1 polypropylene Polymers 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 229920002223 polystyrene Polymers 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 229910000077 silane Inorganic materials 0.000 description 1
- 241000894007 species Species 0.000 description 1
- 230000003595 spectral effect Effects 0.000 description 1
- LXMSZDCAJNLERA-ZHYRCANASA-N spironolactone Chemical compound C([C@@H]1[C@]2(C)CC[C@@H]3[C@@]4(C)CCC(=O)C=C4C[C@H]([C@@H]13)SC(=O)C)C[C@@]21CCC(=O)O1 LXMSZDCAJNLERA-ZHYRCANASA-N 0.000 description 1
- 229920005992 thermoplastic resin Polymers 0.000 description 1
- 229920001187 thermosetting polymer Polymers 0.000 description 1
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
- G03G9/0821—Developers with toner particles characterised by physical parameters
- G03G9/0823—Electric parameters
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G9/00—Developers
- G03G9/08—Developers with toner particles
- G03G9/10—Developers with toner particles characterised by carrier particles
- G03G9/107—Developers with toner particles characterised by carrier particles having magnetic components
- G03G9/108—Ferrite carrier, e.g. magnetite
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Developing Agents For Electrophotography (AREA)
Description
【発明の詳細な説明】 本発明は、電子写真用二成分系現像剤に関するもので、
より詳細には低電気抵抗のフエライト粒子と顕電性トナ
ーとから成り、低電位の電気潜像を現像する用途に適し
た電子写真用二成分系現像剤に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a two-component developer for electrophotography,
More specifically, the invention relates to a two-component electrophotographic developer for electrophotography, which is composed of ferrite particles having low electric resistance and electrophotographic toner and is suitable for developing an electric latent image having low electric potential.
二成分系磁性現像剤を用いる電子写真法においては、顕
電性トナーと磁性キヤリヤとを混合し、この二成分系組
成物を、内部に磁石を備えた現像スリーブ上に供給し
て、この組成物から成る磁気ブラシを形成させ、静電潜
像を有する電子写真感光板にこの磁気ブラシを摺擦せし
めることにより、顕電性トナー像を感光板上に形成させ
る。顕電性トナーは磁性キヤリヤとの摩擦により、感光
板上の静電潜像の電荷とは逆極性の電荷に帯電され、磁
気ブラシ上の顕電性トナー粒子がクーロン力により静電
潜像上に付着して、静電潜像の現像が行われる。一方磁
性キヤリヤはスリーブ内の磁石により吸引されており、
しかもその帯電電荷が静電潜像の電荷と同極性であり、
そのため、磁性キヤリヤはスリーブ上にそのまま残るこ
とになる。鮮明で且つ濃度の高い画像を形成させるため
には、感光板と磁気ブラシとの間に十分に相対的な速度
差を与えて、感光板が磁気ブラシで十分に摺擦されるよ
うにすることが重要である。In the electrophotographic method using a two-component magnetic developer, a sensible toner and a magnetic carrier are mixed, and the two-component composition is supplied onto a developing sleeve having a magnet inside, and the composition is prepared. A magnetic brush made of a material is formed, and the electrophotographic photosensitive plate having an electrostatic latent image is rubbed against the electrophotographic photosensitive plate to form an electrophotographic toner image on the photosensitive plate. Due to the friction with the magnetic carrier, the electrostatic toner is charged with a charge having a polarity opposite to that of the electrostatic latent image on the photosensitive plate, and the electrostatic toner particles on the magnetic brush are transferred to the electrostatic latent image by Coulomb force. And the electrostatic latent image is developed. On the other hand, the magnetic carrier is attracted by the magnet in the sleeve,
Moreover, the charged charge has the same polarity as the charge of the electrostatic latent image,
Therefore, the magnetic carrier remains on the sleeve. In order to form a clear and high-density image, provide a sufficient relative speed difference between the photosensitive plate and the magnetic brush so that the photosensitive plate is sufficiently rubbed by the magnetic brush. is important.
磁性キヤリヤとしては一般に、鉄粉キヤリヤが広く使用
されているが、この鉄粉キヤリヤには未だ多くの欠点が
認められる。即ち、この鉄粉キヤリヤを用いた二成分系
現像剤では、現像感度曲線（静電像と現像スリーブ間の
電位差対画像濃度の曲線）の立上りが急で、階調性に劣
り、中間調の再現性に乏しいという欠点がある。また、
この鉄粉キヤリヤを含む現像剤は硬い磁気ブラシを形成
することがあり、感光層を傷つける可能性があると共
に、ベタ黒部の複写に際しては、形成される画像に、ブ
ラシマーク、即ちブラシの摺擦方向に延びている細くて
短い白線の多数の列が入るという欠点が認められる。更
に、鉄粉キヤリヤは湿度に敏感であり、湿度の影響によ
り現像特性が変化したり、或いはそれ自体錆を発生する
傾向があり、更にまた磁気ブラシの駆動に大きなトルク
を必要とするという問題もある。Iron powder carriers are generally widely used as magnetic carriers, but many drawbacks are still recognized in the iron powder carriers. That is, in the two-component type developer using the iron powder carrier, the developing sensitivity curve (the curve of the potential difference between the electrostatic image and the developing sleeve versus the image density) rises sharply, the gradation is inferior, and the halftone is obtained. It has the drawback of poor reproducibility. Also,
The developer containing the iron powder carrier may form a hard magnetic brush, which may damage the photosensitive layer, and at the time of copying a solid black portion, brush marks, that is, rubbing of the brush on the formed image. The disadvantage is that there are many rows of thin, short white lines extending in the direction. Further, the iron powder carrier is sensitive to humidity, there is a tendency that the development characteristics change due to the influence of humidity, or rust itself is generated, and that a large torque is required to drive the magnetic brush. is there.
近年、二成分系現像剤の磁性キヤリヤとして、フエライ
ト、特にソフトフエライトを用いることが提案されてい
る。フエライトキヤリヤは残留磁化が小さく、磁気ブラ
シの駆動に必要なトルクが比較的小さく、しかも環境条
件下における諸特性の劣化傾向も小さいという利点を有
しているが、その反面として、フエライトキヤリヤは鉄
粉キヤリヤよりも高電気抵抗であることにも関連して、
現像に際してキヤリヤ引き、即ちキヤリヤが感光層側へ
移行するというトラブルや、形成される画像にエツジ効
果が生じるという問題がある。In recent years, it has been proposed to use ferrite, particularly soft ferrite, as a magnetic carrier for a two-component developer. Ferrite carriers have the advantages that the residual magnetization is small, the torque required to drive the magnetic brush is comparatively small, and the tendency of deterioration of various characteristics under environmental conditions is also small. Is also associated with higher electrical resistance than iron powder carrier,
When developing, there is a problem that the carrier is pulled, that is, the carrier moves to the photosensitive layer side, and an edge effect occurs in the formed image.
近年、非晶質シリコン系光導電体層は、表面硬度が高
く、長波長側の光に感度を有し、しかも感度そのものも
良好であるので、電子写真用の感光体として着目されて
いる。In recent years, amorphous silicon-based photoconductor layers have attracted attention as electrophotographic photoreceptors because they have high surface hardness, have sensitivity to light on the long wavelength side, and have good sensitivity themselves.
しかしながら、非晶質シリコンは上述した優れた特性を
有するものの、上記光導電層を十分に厚い層に設けるこ
とが製造技術の面でも、製造コストの面でも困難であ
り、その層厚は、セレン感光層のそれよりもかなり薄い
１０乃至３５μの比較的小さい範囲に制限されているの
が実情である。非晶質シリコン層の厚みが小さいことに
関連して、光導電層上に形成させ得る帯電時の表面電位
も、セレン感光板のそれよりもかなり小さい２００乃至
４００ボルトの範囲に制限され、強いて帯電電位を上げ
ると感光層の絶縁破壊を生じることから、形成される電
荷像の電位コントラストが低いという問題がある。かく
して、通常の二成分系現像剤で現像を行う場合には、ト
ナー像の画像濃度が低下し、また画像濃度を強いて向上
させようとすると、トナー飛散を生じたり、或いはカブ
リ濃度が高くなるという欠点を生じる。However, although amorphous silicon has the above-described excellent properties, it is difficult to provide the photoconductive layer in a sufficiently thick layer in terms of manufacturing technology and manufacturing cost, and the layer thickness is selenium. In reality, it is limited to a relatively small range of 10 to 35 μ, which is considerably thinner than that of the photosensitive layer. Due to the small thickness of the amorphous silicon layer, the surface potential at the time of charging that can be formed on the photoconductive layer is also limited to the range of 200 to 400 V, which is much smaller than that of the selenium photosensitive plate, and it is forcible. When the charging potential is increased, dielectric breakdown of the photosensitive layer occurs, so that the potential contrast of the formed charge image is low. Thus, when developing with a normal two-component developer, the image density of the toner image is lowered, and if an attempt is made to improve the image density by force, toner scatter or fog density becomes high. There are drawbacks.
従つて、本発明の目的は、磁性キヤリヤとしてフエライ
トキヤリヤを含有し、キヤリヤ引きや画像にエツジ効果
を生じることなしに、鮮明で高濃度のトナー像を形成さ
せ得る二成分系現像剤を提供するにある。Accordingly, an object of the present invention is to provide a two-component developer containing a ferrite carrier as a magnetic carrier and capable of forming a clear and high-concentration toner image without causing a carrier pull or an edge effect on an image. There is.
本発明の他の目的は、電位コントラストの低い電荷像か
らも鮮明性と濃度とに優れたトナー像を形成させ得る二
成分系現像剤を提供するにある。Another object of the present invention is to provide a two-component developer capable of forming a toner image excellent in sharpness and density even from a charge image having low potential contrast.
本発明の更に他の目的は、非晶質シリコン系光導電体を
用いる電子写真法の現像に有効に使用し得る二成分系現
像剤を提供するにある。Still another object of the present invention is to provide a two-component developer which can be effectively used for development in electrophotography using an amorphous silicon photoconductor.
本発明によれば、磁気ブラシとしての動的磁気ブラシ抵
抗が６×１０4Ω乃至7.2×１０5Ωの範囲にありかつ平
均粒径が３０乃至４５ミクロンの範囲にあるフェライト
焼結還元粒子から成る磁性キャリヤと、体積抵抗が１×
１０13Ω-cm以上の顕電性トナー粒子とから成ることを
特徴とする電子写真用二成分系現像剤が提供される。According to the present invention, a ferrite sintered reduced particle having a dynamic magnetic brush resistance as a magnetic brush in the range of 6 × 10 4 Ω to 7.2 × 10 5 Ω and an average particle size in the range of 30 to 45 μm is used. Consisting of a magnetic carrier and volume resistance of 1 ×
There is provided a two-component developer for electrophotography, which is characterized by comprising electrophotographic toner particles of 10 13 Ω-cm or more.
本発明の二成分系現像剤が好適に適用される電子写真法
を説明するための第１図において、駆動回転される金属
ドラム１の表面には、非晶質シリコン系光導電体層２が
設けられている。このドラムの周囲には、主帯電用コロ
ナチヤージヤ３；ランプ４、原稿支持透明板５及び光学
系６から成る画像露光機構；トナー７を有する現像機構
８；トナー転写用コロナチヤージヤ９；紙分離用コロナ
チヤージヤ１０；除電ランプ１１；及びクリーニング機
構１２がこの順序に設けられている。In FIG. 1 for explaining an electrophotographic method to which the two-component developer of the present invention is preferably applied, an amorphous silicon photoconductor layer 2 is formed on the surface of a metal drum 1 which is driven and rotated. It is provided. Around the drum, a main charging corona charger 3; an image exposure mechanism including a lamp 4, a document supporting transparent plate 5 and an optical system 6; a developing mechanism 8 having toner 7; a toner transferring corona charger 9; a paper separating corona charger 10 A charge eliminating lamp 11; and a cleaning mechanism 12 are provided in this order.
先ず、光導電体層２をコロナチヤージヤ３で一定極性の
電荷で帯電させる。次いで、ランプ４で複写すべき原稿
１３を照明し、光学系６を経て原稿の光線像で光導電体
層２を露光し、原稿画像に対応する静電潜像を形成させ
る。この静電潜像を、現像機構８によりトナー７で現像
する。転写紙１４を、トナー転写用チヤージャ９の位置
でドラム表面と接触するように供給し、転写紙１４の背
面から静電像と同極性のコロナチヤージを行つて、トナ
ー像を転写紙１４に転写させる。トナー像が転写された
転写紙１４は、分離用コロナチヤージヤ１０の除電によ
つてドラムから静電的に剥離され、定着域（図示せず）
等の処理域に送られる。First, the photoconductor layer 2 is charged by the corona charger 3 with a constant polarity charge. Next, the lamp 4 illuminates the original 13 to be copied, and the photoconductor layer 2 is exposed to the light beam image of the original through the optical system 6 to form an electrostatic latent image corresponding to the original image. The electrostatic latent image is developed with the toner 7 by the developing mechanism 8. The transfer paper 14 is supplied so as to contact the surface of the drum at the position of the toner transfer charger 9, and a corona charge having the same polarity as the electrostatic image is made from the back surface of the transfer paper 14 to transfer the toner image to the transfer paper 14. . The transfer paper 14 on which the toner image has been transferred is electrostatically separated from the drum by the charge removal of the separation corona charger 10 and a fixing area (not shown).
Etc. to the processing area.
トナー転写後の光導電体層２は、除電ランプ１１による
全面露光で残留電荷が消去され、次いでクリーニング機
構１２によつて残留トナーの除去が行われる。After the toner transfer, the photoconductor layer 2 is entirely exposed by the static elimination lamp 11 to erase the residual charges, and then the cleaning mechanism 12 removes the residual toner.
本発明の重要な特徴は、上述した静電潜像の現像に、低
電気抵抗の焼結還元フエライト粒子と、高電気抵抗の顕
電性トナー粒子との組合せから成る二成分系磁性現像剤
を用いることに存する。An important feature of the present invention is that a two-component magnetic developer comprising a combination of low electric resistance sintered reduced ferrite particles and high electric resistance electroscopic toner particles is used in the development of the electrostatic latent image described above. It exists in using.
本発明においては、先ず、種々の磁性キヤリヤの内でも
フエライトキヤリヤを使用する。フエライトキヤリヤ
は、通常の鉄粉キヤリヤに比して、比重が小さくしかも
飽和磁束密度も小さいため、形成される穂が柔かく、そ
の結果として現像に際して、現像用スリーブ乃至はスリ
ーブ内磁石の回転に要するトルクが小さいという利点を
有することが知られている。In the present invention, first of all, the ferrite carrier is used among various magnetic carriers. Ferrite carriers have a smaller specific gravity and a smaller saturation magnetic flux density than ordinary iron powder carriers, so the ears formed are soft, and as a result, during development, the sleeve for development or the magnet inside the sleeve does not rotate. It is known to have the advantage of requiring less torque.
更に、フエライトキヤリヤを用いると、現像剤磁気ブラ
シの電気特性が長期間にわたつて安定しており、しかも
スペント・トナーの発生が少ないという利点がもたらさ
れる。Further, the use of the ferrite carrier has the advantage that the magnetic properties of the developer magnetic brush are stable over a long period of time, and the amount of spent toner generated is small.
しかしながら、既に述べた通り、フエライトキヤリヤ粒
子は、鉄粉キヤリヤに比して約２乃至３桁高い体積固有
抵抗を有する。しかして、通常のフエライトキヤリヤと
顕電性トナーとの組合せから成る二成分系磁性現像剤
は、セレン系感光体上の静電像の現像には高濃度のトナ
ー像を与えるとしても、非晶質シリコン系感光体上の静
電像の現像に用いると、著しく濃度の低い画像濃度しか
与えないことがわかつた。However, as already mentioned, the ferrite carrier particles have a volume resistivity higher by about two to three orders of magnitude than the iron powder carriers. Therefore, a two-component magnetic developer composed of a combination of a normal ferrite carrier and a sensible toner does not give a high-concentration toner image to the development of an electrostatic image on a selenium-based photoconductor. It has been found that when used in the development of electrostatic images on crystalline silicon-based photoreceptors, it gives remarkably low image densities.
本発明に用いるフエライトキヤリヤは、磁気ブラシとし
ての動的電気抵抗が６×１０4乃至7.2×１０5Ω、特に
１×１０5乃至5.8×１０5Ωの範囲にあるフエライト焼
結還元粒子から成ることが顕著な特徴である。即ち、通
常のフエライトキヤリヤは、一般に体積固有抵抗が１×
１０10Ω・cm以上で動的電気抵抗が１×１０9Ω以上の
高い値を有する。最近に至つて、特開昭５９−４８７７
４号公報には、Fe2O3当りの２価金属酸化物成分のモル
比を0.85以下としたフエライト造形物を電子写真現像用
キヤリヤーとして用いることが開示されているが、この
キヤリヤーの体積固有抵抗は、通常のフエライトに比し
て低いとしても、未だ8.5×１０6乃至２×１０9Ω・cm
（動的電気抵抗で8.5×１０5乃至２×１０8Ω）のオー
ダーであり、非晶質シリコン系光導電体上の静電潜像を
高濃度に現像するという目的には不満足なものである。The ferrite carrier used in the present invention is made from ferrite reduced particles having a dynamic electric resistance of 6 × 10 4 to 7.2 × 10 5 Ω, particularly 1 × 10 5 to 5.8 × 10 5 Ω as a magnetic brush. Is a remarkable feature. That is, an ordinary ferrite carrier generally has a volume resistivity of 1 ×
It has a high dynamic electric resistance of 1 × 10 9 Ω or more at 10 10 Ω · cm or more. Recently, JP-A-59-4877
Japanese Unexamined Patent Publication No. 4 discloses the use of a ferrite modeled product having a molar ratio of divalent metal oxide component per Fe 2 O 3 of 0.85 or less as a carrier for electrophotographic development. The resistance is still 8.5 × 10 6 to 2 × 10 9 Ω · cm even if it is lower than that of ordinary ferrite.
(Dynamic electric resistance is 8.5 × 10 5 to 2 × 10 8 Ω), which is unsatisfactory for the purpose of developing a high density electrostatic latent image on an amorphous silicon photoconductor. is there.
本発明は、フエライト焼結粒子を水素還元することによ
り動的電気抵抗が６×１０4Ω・cm乃至7.2×１０5Ω-cm
の範囲にあるフエライトキヤリヤの製造に成功し、この
キヤリヤを体積固有抵抗が１×１０13Ω-cmの顕電性ト
ナー粒子と組合せて、非晶質シリコン光導電体上の電荷
像の現像に用いることにより、鮮明さ及び濃度に優れた
トナー像の形成が可能となつたものである。In the present invention, the dynamic electrical resistance is reduced from 6 × 10 4 Ω · cm to 7.2 × 10 5 Ω-cm by reducing the sintered ferrite particles with hydrogen.
We have succeeded in producing a ferrite carrier in the range of 1.0 to 1.0, and combined this carrier with electroscopic toner particles having a volume resistivity of 1 × 10 13 Ω-cm to develop a charge image on an amorphous silicon photoconductor. It is possible to form a toner image excellent in sharpness and density by using the toner.
本明細書において、磁気ブラシとしての動的電気抵抗と
は、磁気ブラシによる現像条件下に動的に測定される電
気抵抗値であり、下記の方法により求められる値を意味
する。即ち、電子電真感光体ドラムと同寸法のアルミ製
電極ドラムを感光体ドラムに置換えて設置し、現像スリ
ーブ上に現像剤を供給して磁気ブラシを形成させ、この
磁気ブラシを電極ドラムと摺擦させ、このスリーブとド
ラムとの間に電圧を印加して両者間に流れる電流を測定
することにより、算出された抵抗値を意味する。測定に
当つては、トナーとキヤリヤとから成る現像剤の場合に
は印加電圧を５０Ｖとし、キヤリヤ単独で磁気ブラシを
形成させて測定する場合には印加電圧を２０Ｖとして、
使用する複写機に備わつている現像装置の現像条件（例
えば、ドラム−スリーブ間距離や磁気ブラシの移動速度
など）に従つて測定する。即ち、この測定によつて得ら
れる抵抗値は使用する複写機の現像条件に即した抵抗値
であることが理解される。以下、この測定法による電気
抵抗をＤ−Ｓ抵抗と呼ぶ。In the present specification, the dynamic electric resistance as a magnetic brush is an electric resistance value dynamically measured under the developing condition by the magnetic brush, and means a value obtained by the following method. That is, an aluminum electrode drum having the same size as the electron-electric photoconductor drum is installed in place of the photoconductor drum, a developer is supplied onto the developing sleeve to form a magnetic brush, and the magnetic brush is slid on the electrode drum. The resistance value is calculated by rubbing and applying a voltage between the sleeve and the drum and measuring the current flowing between them. In the measurement, the applied voltage is 50 V in the case of the developer composed of the toner and the carrier, and the applied voltage is 20 V in the case where the carrier is used alone to form the magnetic brush.
The measurement is performed according to the developing conditions of the developing device provided in the copying machine used (for example, the distance between the drum and the sleeve, the moving speed of the magnetic brush, etc.). That is, it is understood that the resistance value obtained by this measurement is a resistance value according to the developing conditions of the copying machine used. Hereinafter, the electric resistance measured by this measuring method is referred to as the DS resistance.
一般に、帯電電位をＥ、現像電流をｉ、現像剤磁気ブラ
シの電気抵抗をＲとすれば、下記式 Ｅ＝ｉＲ……(1) の関係が成立つと考えられる。現像電流ｉにトナー濃度
が比例するとすれば、帯電電位(E)の小さい感光体に対
しては、磁気ブラシの抵抗(R)を下げて現像電流(i)を可
及的に大きく取り出すことが考えられるかもしれない。
また、現像剤磁気ブラシの電気抵抗Ｒを小さくするため
に、磁性キヤリヤの電気抵抗、即ちＤ−Ｓ抵抗を下げる
ことが考えられるかもしれない。Generally, if the charging potential is E, the developing current is i, and the electric resistance of the developer magnetic brush is R, the following equation E = iR (1) is considered to be established. If the toner density is proportional to the developing current i, it is possible to lower the resistance (R) of the magnetic brush and take out the developing current (i) as large as possible for a photoconductor having a small charging potential (E). You might think.
Further, in order to reduce the electric resistance R of the developer magnetic brush, it may be considered to reduce the electric resistance of the magnetic carrier, that is, the DS resistance.
しかしながら、本発明者等は、磁気ブラシの動的及び現
像条件下での電気抵抗とトナー像の濃度との関係は、上
記式(1)の双曲線的関係にあるのではなく、一定の電気
抵抗値の所に屈曲点があり、この屈曲点以下では画像濃
度が飛躍的に向上することを見出したものである。第２
図は、現像剤磁気ブラシの動的及び現像条件下での抵抗
とトナー像の濃度との関係を示すプロツトであり、非晶
質シリコン感光体とフエライトキヤリヤ現像剤との組合
せでは前述した臨界点を生じることが明白であろう。However, the inventors of the present invention have found that the relationship between the electric resistance of the magnetic brush under dynamic and developing conditions and the density of the toner image is not a hyperbolic relationship of the above formula (1), but a constant electric resistance. It has been found that there is a bending point at the value, and the image density is dramatically improved below this bending point. Second
The figure is a plot showing the relationship between the resistance of the developer magnetic brush under dynamic and developing conditions and the density of the toner image. The combination of the amorphous silicon photoconductor and the ferrite carrier developer has the above-mentioned critical value. It will be clear that it gives rise to points.
第２図からも明らかな通り、高濃度でしかもブラシマー
クが無い高画質のトナー像を、非晶質シリコン系感光体
上に形成させるという見地からは、現像剤磁気ブラシの
動的且つ現像条件下での電気抵抗（Ｄ−Ｓ抵抗）を４×
１０6Ω乃至５×１０7Ω、好ましくは８×１０6Ω乃至
４×１０7Ω，特に好ましくは１×１０7Ω乃至２×１０
7Ωの範囲とすることが必要となる。As is clear from FIG. 2, from the standpoint of forming a high-density toner image of high density and without brush marks on the amorphous silicon-based photoconductor, the dynamic and development conditions of the developer magnetic brush are used. 4 x lower electrical resistance (DS resistance)
10 6 Ω to 5 × 10 7 Ω, preferably 8 × 10 6 Ω to 4 × 10 7 Ω, particularly preferably 1 × 10 7 Ω to 2 × 10
It must be in the range of 7 Ω.
現像剤磁気ブラシ全体の抵抗は当然のことながらキヤリ
ヤ粒子の抵抗と、トナー粒子の抵抗とに依存するが、ト
ナー粒子の電気抵抗は、感光層表面から転写紙へのトナ
ー像の転写に重大な影響を及ぼし、トナー粒子の体積抵
抗が１×１０13Ω-cmよりも低い場合には、転写に際し
て、トナー粒子の転写効率の低下及びトナー像の飛散乃
至は輪郭のブロードニング等を生じるために、前記基準
値よりも下げることはできない。この意味では、キヤリ
ヤとして電気抵抗の比較的小さいものを用いることが有
効になる。The resistance of the developer magnetic brush as a whole naturally depends on the resistance of the carrier particles and the resistance of the toner particles, but the electric resistance of the toner particles is important for the transfer of the toner image from the surface of the photosensitive layer to the transfer paper. If the volume resistance of the toner particles is lower than 1 × 10 13 Ω-cm, the transfer efficiency of the toner particles may be lowered and the toner image may be scattered or the contour may be broadened during transfer. However, it cannot be lowered below the reference value. In this sense, it is effective to use a carrier having a relatively low electric resistance.
本発明において、画像濃度を飛躍的向上させるという見
地から、フエライトキヤリヤのＤ−Ｓ抵抗は前述した上
限値に制限される。また、トナー像の濃度は、キヤリヤ
磁気ブラシの抵抗が或る値よりも小さくなるとかえつて
減少するようになり、しかも電気抵抗が小さくなり過ぎ
ると、磁気ブラシを介して静電像の電荷のリーク等が生
じて、ベタ黒の画像部に微細な白地抜けの模様（ブラシ
マーク）等が生じるようになる。かかる見地から、本発
明においては、キヤリヤのＤ−Ｓ抵抗は、前述した下限
値以上に制限される。In the present invention, the D-S resistance of the ferrite carrier is limited to the above-mentioned upper limit from the viewpoint of dramatically improving the image density. Further, the density of the toner image is rather decreased when the resistance of the carrier magnetic brush becomes smaller than a certain value, and when the electric resistance becomes too small, the charge of the electrostatic image leaks through the magnetic brush. As a result, a fine white background pattern (brush mark) or the like is generated in the solid black image portion. From this point of view, in the present invention, the DS resistance of the carrier is limited to the above lower limit value or more.
本発明に用いる低Ｄ−Ｓ抵抗のフエライトキヤリヤー
は、焼結フエライト粒子をＤ−Ｓ抵抗が上記範囲となる
ように還元、好適には水素還元することにより得られ
る。原料のフエライト焼結粒子はそれ自体公知のもので
あり、公知の焼結フエライト粒子、特に球状の焼結フエ
ライト粒子が有利に使用される。フエライトの組成も公
知のものであり、一般にソフトフエライトと呼ばれるも
の、例えばこれに限定されるものでないが、Zn系フエラ
イト、Ni系フエライト、Cu系フエライト、Mn系フエライ
ト、Mn-Zn系フエライト、Mn-Mg系フエライト、Cu-Zn系
フエライト、Ni-Zn系フエライト、Mn-Cu-Zn系フエライ
ト等が挙げられる。好適なフエライトは、原子重量％
で、Fe３５乃至６５％、Cu５乃至１５％、Zn５乃至１５
％及びMn０乃至0.5％から成るCu-Zn系又はCu-Zn-Mn系フ
エライトである。The low D-S resistance ferrite carrier used in the present invention is obtained by reducing the sintered ferrite particles so that the D-S resistance falls within the above range, preferably hydrogen reduction. The raw material sintered ferrite particles are known per se, and known sintered ferrite particles, particularly spherical sintered ferrite particles, are advantageously used. The composition of ferrite is also known, and is generally called soft ferrite, such as, but not limited to, Zn-based ferrite, Ni-based ferrite, Cu-based ferrite, Mn-based ferrite, Mn-Zn-based ferrite, Mn. -Mg-based ferrite, Cu-Zn-based ferrite, Ni-Zn-based ferrite, Mn-Cu-Zn-based ferrite, and the like. The preferred ferrite is atomic weight percent
And Fe35 to 65%, Cu5 to 15%, Zn5 to 15
% And Mn 0 to 0.5% Cu-Zn system or Cu-Zn-Mn system ferrite.
この焼結フエライト粒子を、例えば水素気流中３００乃
至５００℃、特に３４０乃至４２０℃の温度で還元す
る。必要な処理時間は、温度や水素通気量によつても相
違するが、一般的に言つて、３０分乃至１時間の内か
ら、生成物のＤ−Ｓ抵抗が前述した範囲となる時間を選
ぶ。この還元により焼結フエライト粒子の少なくとも表
面部分の金属成分が酸化状態の低い酸化物、即ち原子価
の低い状態に移行し、これにより電気抵抗の低下を生じ
るものと認められる。還元処理は、水素雰囲気中で行う
ことが望ましいが、一酸化炭素を用いて行うことも可能
である。The sintered ferrite particles are reduced, for example, in a hydrogen stream at a temperature of 300 to 500 ° C., particularly 340 to 420 ° C. The required treatment time varies depending on the temperature and the hydrogen aeration amount, but generally speaking, a time within which the DS resistance of the product falls within the above-mentioned range is selected from the range of 30 minutes to 1 hour. . It is recognized that this reduction causes the metal component of at least the surface portion of the sintered ferrite particles to shift to an oxide having a low oxidation state, that is, a state having a low valence, thereby causing a decrease in electric resistance. The reduction treatment is preferably performed in a hydrogen atmosphere, but carbon monoxide can also be used.
また本発明において用いる焼結還元フェライト粒子は、
平均粒径が３０乃至４５ミクロンの範囲にあることも重
要である。前述したＤ−Ｓ抵抗、即ち磁気ブラシとして
の動的抵抗は、キャリヤ粒子の粒径によっても左右さ
れ、フェライトキャリヤの粒径を小さくすることによっ
て、磁気ブラシの抵抗を任意の低い値に調節し得るもの
だからである。これは、フェライトキャリヤの粒径を小
さくすることにより、磁気ブラシ中或いは磁気ブラシと
スリーブ乃至は感光層表面との接触点の数が増大するた
めと思われる。従って、上記範囲よりも粒径の大きい焼
結還元フェライト粒子を用いた場合には、該粒子自体の
抵抗が比較的低いものであっても、磁気ブラシとしての
動的抵抗を本発明で規定する範囲内に設定することが困
難となる。Further, the sintered reduced ferrite particles used in the present invention,
It is also important that the average particle size be in the range of 30 to 45 microns. The above-mentioned D-S resistance, that is, the dynamic resistance of the magnetic brush is also influenced by the particle size of the carrier particles, and the resistance of the magnetic brush is adjusted to an arbitrary low value by reducing the particle size of the ferrite carrier. Because you get what you get. This is considered to be because the number of contact points in the magnetic brush or between the magnetic brush and the sleeve or the surface of the photosensitive layer is increased by reducing the particle size of the ferrite carrier. Therefore, when the sintered reduced ferrite particles having a particle size larger than the above range are used, the dynamic resistance as a magnetic brush is specified by the present invention even if the particles themselves have a relatively low resistance. It is difficult to set within the range.
用いるトナーは、前述した転写性の見地から１×１０13
Ω-cm、特に少なくとも５×１０13Ω-cmの電気抵抗を有
するものでなければならない。更に、当然のことなが
ら、このトナー粒子は顕電性と定着性とを有する着色ト
ナーでなければならない。結着剤樹脂中に、着色顔料、
荷電制御剤等を分散させた粒径５乃至３０ミクロンの粒
状組成物が使用される。樹脂としては、熱可塑性樹脂
や、未硬化乃至は初期縮合物の熱硬化性樹脂が使用され
る。その適当な例は、重要なものの順序に、ポリスチレ
ン等のビニール芳香族樹脂、アクリル系樹脂、ポリビニ
ルアセタール樹脂、ポリエステル樹脂、エポキシ樹脂、
フエノール樹脂、石油樹脂、オレフイン樹脂等である。
顔料としては例えばカーボンブラツク、カドミウムエロ
ー、モリブデンオレンジ、ピラゾロンレツド、フアスト
バイオレツトＢ、フタロシアニンブルー等の１種又は２
種以上が使用され、荷電制御剤としては、例えばニグロ
シンベース（ＣＩ５０４１５）、オイルブラツク（ＣＩ
２６１５０）、スピロンブラツク等の油溶性染料や、ナ
フテン酸金属塩、脂肪酸金属石鹸、樹脂酸石鹸等が必要
により使用される。The toner used is 1 × 10 13 from the viewpoint of transferability described above.
It must have an electrical resistance of Ω-cm, especially at least 5 × 10 13 Ω-cm. In addition, it goes without saying that the toner particles must be colored toners having sensible and fixing properties. In the binder resin, coloring pigment,
A granular composition having a particle size of 5 to 30 microns in which a charge control agent or the like is dispersed is used. As the resin, a thermoplastic resin or a thermosetting resin of an uncured or initial condensation product is used. Suitable examples are, in order of importance, vinyl aromatic resins such as polystyrene, acrylic resins, polyvinyl acetal resins, polyester resins, epoxy resins,
Examples include phenolic resins, petroleum resins, and olefin resins.
Examples of the pigment include carbon black, cadmium yellow, molybdenum orange, pyrazolone red, fast violet red B, phthalocyanine blue, and the like, or two or more.
As the charge control agent, for example, nigrosine base (CI50415), oil black (CI) is used.
26150), oil-soluble dyes such as spirone black, metal naphthenate salts, fatty acid metal soaps, resin acid soaps and the like are used as necessary.
フエライトキヤリヤと顕電性トナーとは、一般に１０
０：６乃至１００：１１の重量比で使用するのがよい。
この量比も現像剤の磁気ブラシの電気抵抗に影響を及ぼ
す。即ち、フエライトキヤリヤの量比が大きくなると、
現像剤の磁気ブラシの電気抵抗が小さくなる傾向を示
す。両者の最適比率は、フエライトキヤリヤ及び顕電性
トナーの比表面積にも密接に関連する。本発明の好適態
様では、磁気ブラシを形成する混合物のトナー濃度（Ct
％）が、下記式 式中、Scはフエライトキヤリヤの比表面積（cm2／ｇ：
透過法による実測値）、Stはトナーの比表面積（cm2／
ｇ：コールターカウンターを用いて測定した平均粒径を
基に、トナーが真球であると仮定して計算した有効比表
面積であり、平均粒径から得られるトナーの半径をγ
（cm）とし、トナーの真比重をρ（ｇ／cm3）とした場
合、St＝３／γ・ρで計算した値である）、ｋは0.80乃
至1.07の数である、 を満足する濃度で現像を行う。Ferrite carrier and electrophotographic toner are generally 10
It is preferred to use it in a weight ratio of 0: 6 to 100: 11.
This quantity ratio also affects the electric resistance of the magnetic brush of the developer. That is, if the quantity ratio of the ferrite carrier increases,
The magnetic brush of the developer tends to have low electric resistance. The optimum ratio of the two is closely related to the specific surface areas of the ferrite carrier and the electrophotographic toner. In a preferred embodiment of the invention, the toner concentration (Ct
%) Is the following formula In the formula, Sc is the specific surface area of the ferrite carrier (cm 2 / g:
Measured by the transmission method), St is the specific surface area of the toner (cm 2 /
g: Effective specific surface area calculated based on the average particle size measured by using a Coulter counter, assuming that the toner is a sphere, and the radius of the toner obtained from the average particle size is γ.
(Cm) and the true specific gravity of the toner is ρ (g / cm 3 ), it is a value calculated by St = 3 / γ · ρ), and k is a number from 0.80 to 1.07. To develop.
先ず、前記式(2)における右辺の項Sc/(St+Sc)は、キヤ
リヤ及びトナーの比表面積に関する項であり、具体的に
は、キヤリヤとトナーとを等重量混合した組成物の全表
面積当りのキヤリヤの占める表面積の割合（以下単にキ
ヤリヤ表面積占有率と呼ぶ）を表わす数値である。First, the term Sc / (St + Sc) on the right side of the formula (2) is a term relating to the specific surface area of the carrier and the toner, and specifically, the total surface area of the composition in which the carrier and the toner are mixed in equal weight. It is a numerical value showing the ratio of the surface area occupied by the carrier per unit (hereinafter simply referred to as the carrier surface area occupation rate).
しかして、本発明のこの態様においては、このキヤリヤ
表面積占有率乃至はその近傍値とトナー濃度とが等しく
なるような条件で、二成分系現像剤による静電像の現像
を行うと、画像の濃度の向上、カブリ濃度の低下、解像
度の向上及び階調性の向上がもたらされるものである。Therefore, in this aspect of the present invention, when the electrostatic image is developed with the two-component developer under the condition that the carrier surface area occupancy rate or its neighborhood value is equal to the toner density, The density is improved, the fog density is reduced, the resolution is improved, and the gradation is improved.
トナー濃度（Ct％）とキヤリヤ表面積占有率（Sc/(St+S
c),％）とのずれは、両者の比率、即ち ｋ＝Ｃｔ／〔Ｓｃ／（Ｓｔ＋Ｓｃ）〕 係数ｋを求めることにより評価することができる。Toner concentration (Ct%) and carrier surface area occupation rate (Sc / (St + S
The difference between c) and%) can be evaluated by obtaining the ratio of the two, that is, k = Ct / [Sc / (St + Sc)] coefficient k.
この係数ｋは使用するフエライトキヤリヤの形状によつ
て相違するが本発明においては、この係数ｋを前述した
0.80乃至1.07の値、特に球状フエライト粒子では0.90乃
至1.04の範囲とすることにより、高い画像濃度、低いカ
ブリ濃度、高い解像力及び優れた階調性が得られ、しか
もこれらの特性は現像開始初期のみならず、10000枚も
の連続複写後においても殆んど低下しないという効果が
達成される。This coefficient k differs depending on the shape of the ferrite carrier used, but in the present invention, this coefficient k has been described above.
A value of 0.80 to 1.07, especially in the range of 0.90 to 1.04 for spherical ferrite particles, high image density, low fog density, high resolution and excellent gradation can be obtained. In addition, an effect is achieved in which there is almost no deterioration even after continuous copying of 10,000 sheets.
本発明の二成分系現像剤は、非晶質シリコン系光導電体
層を用いる電子写真法の現像に特に有用である。The two-component developer of the present invention is particularly useful for electrophotographic development using an amorphous silicon photoconductor layer.
非晶質シリコン系光導電体層としては、それ自体公知の
任意のものが使用され、例えばシランガスのプラズマ分
解等で基板上に析出される非晶質シリコンが使用され、
このものは、水素やハロゲン等でドーピングされ、更に
ボロンやリン等の周期律表第III族または第Ｖ族元素で
ドーピングされたものであつてよい。As the amorphous silicon-based photoconductor layer, any known per se is used, for example, amorphous silicon deposited on the substrate by plasma decomposition of silane gas is used,
This may be doped with hydrogen, halogen or the like, and further doped with a group III or group V element of the periodic table such as boron or phosphorus.
代表的なアモルフアスシリコン感光体の物性値は、暗導
電率が１０-12Ω-1・cm-1、活性化エネルギ＜0.85ｅ
Ｖ、光導電率＞１０-7Ω-1・cm-1、光学的バンドギヤツ
プ1.7〜1.9ｅＶであり、また結合水素量は１０〜２０原
子％の量でその膜の誘電率は11.5〜12.5の範囲にあるも
のである。The physical properties of a typical amorphous silicon photoconductor are as follows: dark conductivity of 10 -12 Ω -1 cm -1 , activation energy <0.85e.
V, photoconductivity> 10 -7 Ω -1 cm -1 , optical bandgap 1.7 to 1.9 eV, and the amount of bonded hydrogen is 10 to 20 atomic%, and the dielectric constant of the film is 11.5 to 12.5. It is in the range.
この非晶質シリコン光導電層は、ドーピング種に応じて
プラス荷電やマイナス荷電も可能であり、コロナチヤー
ジヤへの印加電圧は５乃至８ＫＶの範囲が一般的であ
る。The amorphous silicon photoconductive layer can be positively or negatively charged depending on the doping species, and the voltage applied to the corona charger is generally in the range of 5 to 8 KV.
本発明によれば、非晶質シリコン光導電体層の膜厚が１
０乃至３５μｍのように小さく、その結果として帯電電
位が著しく小さい場合にも高濃度の画像形成が可能とな
るという顕著な利点がある。しかも、小さい膜厚の感光
層が使用可能であることは、感光体のコストを下げる上
で顕著な利点をもたらすのみならず、感光層中での光拡
散等が防止され、その結果として形成されるトナー像の
解像力も向上するという利点をも生じる。According to the invention, the amorphous silicon photoconductor layer has a thickness of 1
It is as small as 0 to 35 μm, and as a result, there is a remarkable advantage that a high-density image can be formed even when the charging potential is extremely small. Moreover, the use of a photosensitive layer having a small film thickness not only provides a significant advantage in reducing the cost of the photosensitive member, but also prevents light diffusion in the photosensitive layer, resulting in the formation. There is also an advantage that the resolution of the toner image is improved.
本発明の二成分系現像剤は、勿論、非晶質シリコン光導
電層以外の光導電層、例えばセレン感光板、CdS感光
板、有機感光板（OPC）等に形成された電荷像を現像す
るのにも有効であり、この場合にも、キヤリヤ引きやエ
ツジ効果のないトナー画像を、電位コントラストの小さ
い電荷像に対しても、高濃度で形成させ得るという利点
がある。The two-component developer of the present invention, of course, develops a charge image formed on a photoconductive layer other than the amorphous silicon photoconductive layer, such as a selenium photosensitive plate, a CdS photosensitive plate, an organic photosensitive plate (OPC). This is also effective in this case, and in this case also, there is an advantage that a toner image having no carrier pulling or edge effect can be formed with high density even for a charge image having a small potential contrast.
実施例 フエライトキヤリヤのＤＳ抵抗と複写物との関連を調べ
るために第１図に示されている各機構を備えた複写装置
を用い、トナーと4.0×１０4乃至8.5１×１０6Ωの範囲
にある種々のＤ−Ｓ抵抗を有するフエライトキヤリヤと
から成る現像剤を用いて複写テストを行つた。EXAMPLE In order to investigate the relationship between the DS resistance of the ferrite carrier and the copy, a copying machine equipped with each mechanism shown in FIG. 1 was used, and toner and 4.0 × 10 4 to 8.51 × 10 6 Ω were used. Duplicate tests were carried out with developers comprising ferrite carriers having various D-S resistances in the range.
複写装置としては以下の条件に設定し使用した。The copying machine was used under the following conditions.
感光体：直径９０mmAl製基体上にボロンをドープしたａ
−Si：Ｈをグロー放電分解法により２０μｍの膜厚に堆
積させた感光体 画像露光用光源：感光体表面上での光強度６０μＷ／cm
2（ただし６００ｎｍ以上の分光強度は１０μＷ／cm2以
下）に設定した白色螢光灯 除電光源：緑色発光の冷陰極放電管 クリーニング部：ブレードクリーニング方式 主帯電：コロナ帯電器（＋6.2ＫＶ印加） 転写停電： 〃 （＋5.7ＫＶ印加） 複写速度：感光体ドラム回転速度１６cm／sec 現像部：スリーブ回転速度 ２３cm／sec 現像磁石強度 １０００ガウス 穂切間隔 1.0mm 現像領域：感光体と現像スリーブとを共に時計方向に回
転させ、Ｄ−Ｓ間のギヤツプは1.5mmに固定した。Photoreceptor: Boron-doped a substrate with a diameter of 90 mm Al
-Si: H deposited on the photoconductor by glow discharge decomposition to a film thickness of 20 μm Image exposure light source: light intensity on the photoconductor surface of 60 μW / cm
White fluorescent lamp set to 2 (however, spectral intensity of 600 nm or more is 10 μW / cm 2 or less) Static erasing light source: green light emitting cold cathode discharge tube Cleaning unit: blade cleaning method Main charging: corona charger (+6.2 KV applied) Transfer blackout: 〃 (+ 5.7KV applied) Copy speed: Photoconductor drum rotation speed 16cm / sec Development unit: Sleeve rotation speed 23cm / sec Development magnet strength 1000 gauss Ear cutting interval 1.0mm Development area: Photoconductor and development sleeve Both were rotated clockwise and the gear between D and S was fixed at 1.5 mm.
現像剤としてはトナーは同じ物に使用し、前述した範囲
で種々の動的電気抵抗を有するフエライトキヤリヤと組
合せたものを使用した。As the developer, the same toner was used, and a toner was used in combination with a ferrite carrier having various dynamic electric resistances within the above-mentioned range.
(a)フエライトキヤリヤ 電気抵抗（２０Ｖ印加Ｄ−Ｓ抵抗）： 4.0×１０4〜8.5１×１０6Ω Ｄ−Ｓ抵抗の測定は、前述した複写速度、現像部及び現
像領域の各条件をそのまま使用し、感光体ドラムの代わ
りにドラムと同じ大きさのＡι製電極ドラムを装着し、
スリーブとドラムとの間に２０Ｖの電圧を印加して両者
間に流れる電流を測定することにより算出した値であ
る。(a) Ferrite carrier electrical resistance (20V applied D-S resistance): 4.0 × 10 4 to 8.51 × 10 6 Ω For measuring the D-S resistance, the above-mentioned copying speed, developing unit and developing region conditions were measured. Use as it is, and instead of the photoconductor drum, attach an Aι electrode drum of the same size as the drum,
It is a value calculated by applying a voltage of 20 V between the sleeve and the drum and measuring the current flowing between them.
飽和磁化：全て７０emu／ｇ 中心粒径：全て４０μｍ (b)トナー (i)組成 ハイマーＳＢＭ−７３（スチレン系樹脂：三洋化成工業
K.K製）……８７重量部 ビスコール５５０Ｐ（低分子量ポリプロピレン：三洋化
成工業K.K製）……５重量部 スペシヤルブラツク４（カーボンブラツク：デグサ社
製）……5.5重量部 ボントロンＳ−３２（染料：オリエント化学社製）……
1.5重量部 (ii)調製 上記組成から成る混合物を熱三本ロールミルで充分に熔
融混練分散を行い、次いで混練物を取り出し冷却後粗粉
砕機（ロートプレツクスカツテイングミル：アルピネ社
製）で２mm程度の大きさに粗粉砕し、その後超高速ジエ
ツトミル（NIPPONPNEUMATIC MFC Co.LTD製）にて微粉砕
して５〜２０μ程度の粒径を有するトナーに調製した。
このトナーの比表面積は４３６０cm2／ｇ又、体積固有
抵抗は4.5×１０14Ωcmであつた。Saturation magnetization: All 70emu / g Central particle size: All 40μm (b) Toner (i) Composition Hymer SBM-73 (styrene resin: Sanyo Chemical Industries
KK) 87 parts by weight Viscor 550P (low molecular weight polypropylene: Sanyo Chemical Industries KK) 5 parts by weight Special black 4 (carbon black: manufactured by Degussa) 5.5 parts by weight Bontron S-32 (dye: Orient) (Chemical company) ……
1.5 parts by weight (ii) Preparation The mixture having the above composition was melt-kneaded and dispersed sufficiently with a hot three-roll mill, and the kneaded product was taken out and cooled, and then 2 mm with a coarse crusher (Rotprex cutting mill: manufactured by Alpine). Coarsely pulverized to a size of about 5 μm, and then finely pulverized with an ultra high speed jet mill (manufactured by NIPPON PNEUMATIC MFC Co. LTD) to prepare a toner having a particle size of about 5 to 20 μm.
The specific surface area of this toner was 4360 cm 2 / g, and the volume resistivity was 4.5 × 10 14 Ωcm.
これらのフエライトキヤリヤとトナーとを比表面積の関
係から適正トナー濃度となるように混合し、第１表に示
す現像剤を調整した。These ferrite carriers and toner were mixed so as to have an appropriate toner concentration in view of the relationship of specific surface area, and the developers shown in Table 1 were prepared.
この第１表に示すＡ乃至Ｇの現像剤を用いて複写テスト
を行つた結果を第２表に示す。 Table 2 shows the results of a copy test conducted using the developers A to G shown in Table 1.
この第２表に示した実験結果から、キヤリヤのＤ−Ｓ抵
抗が8.0×１０4乃至7.1×１０5Ω（表中Ｂ、Ｃ、Ｄ、
Ｅ）の現像剤を用いた場合には、高濃度の複写物が得ら
れた。これらＢ乃至Ｅの現像剤の中でも特にキヤリヤの
Ｄ−Ｓ抵抗が1.0×１０5乃至7.1×１０5Ω（表中Ｃ、
Ｄ、Ｅ）は画像濃度（I.D.）も高く、階調性や解像度に
優れ、ブラシマーク、カブリ、エツジ効果による白ぬけ
及び尾引き現像等のない鮮明な複写画像が得られた。そ
して特に現像剤Ｃ、Ｄの画像濃度が高かつた。 From the experimental results shown in Table 2, the DS resistance of the carrier is 8.0 × 10 4 to 7.1 × 10 5 Ω (in the table, B, C, D,
When the developer of E) was used, a high density copy was obtained. Among these B to E developers, the DS resistance of the carrier is 1.0 × 10 5 to 7.1 × 10 5 Ω (C in the table,
D and E) also have high image density (ID), excellent gradation and resolution, and clear copy images without brush marks, fog, white spots due to the edge effect, and tailing development were obtained. The image densities of the developers C and D were particularly high.
また第１表におけるキヤリヤのＤ−Ｓ抵抗と第２表にお
けるI.Dとの関係を示したグラフ図が第３図である。こ
のグラフ図から、キヤリヤのＤ−Ｓ抵抗が６×１０4乃
至7.2×１０5Ωの範囲でI.D.のピークが存在し、この範
囲の現像剤を使用すれば画像濃度1.1以上で高品位な複
写物が得られることを示している。FIG. 3 is a graph showing the relationship between the DS resistance of the carrier in Table 1 and the ID in Table 2. From this graph, there is an ID peak in the carrier DS resistance range of 6 × 10 4 to 7.2 × 10 5 Ω, and if a developer in this range is used, a high-quality copy with an image density of 1.1 or more can be obtained. It indicates that the product is obtained.
第１図は本発明の電子写真法を説明するための図であ
り、図中２は非晶質シリコン系光導電体層、３は主帯電
用コロナチヤージヤ、４は露光用ランプ、８は現像機
構、９は転写用コロナチヤージヤ、１１は除電ランプ及
び１２はクリーニング機構を夫々表わす。 第２図は現像剤のＤ−Ｓ抵抗とI.Dとの関係を示すグラ
フ図、 第３図はキヤリヤのＤ−Ｓ抵抗とI.Dとの関係を示すグ
ラフ図である。 第４図は、フエライトキヤリヤーの粒径とこのキヤリヤ
ーを用いた現像剤（適正トナー濃度）のＤ−Ｓ抵抗との
関係を示すグラフ図である。FIG. 1 is a diagram for explaining the electrophotographic method of the present invention, in which 2 is an amorphous silicon photoconductor layer, 3 is a main charging corona charger, 4 is an exposure lamp, and 8 is a developing mechanism. , 9 is a transfer corona charger, 11 is a charge eliminating lamp, and 12 is a cleaning mechanism. FIG. 2 is a graph showing the relationship between the D-S resistance of the developer and the ID, and FIG. 3 is a graph showing the relationship between the D-S resistance of the carrier and the ID. FIG. 4 is a graph showing the relationship between the particle size of the ferrite carrier and the DS resistance of the developer (appropriate toner concentration) using this carrier.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 東口 照昭 大阪府大阪市東区玉造１丁目２番28号 三 田工業株式会社内 (72)発明者 川上 善信 大阪府大阪市東区玉造１丁目２番28号 三 田工業株式会社内 (56)参考文献 特開 昭59−75269（ＪＰ，Ａ) 特開 昭56−92545（ＪＰ，Ａ) 特開 昭58−195851（ＪＰ，Ａ) 特開 昭57−177161（ＪＰ，Ａ) 特開 昭58−179850（ＪＰ，Ａ) 特開 昭55−85426（ＪＰ，Ａ) ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Teruaki Higashiguchi 1-2-2 Tamatsukuri, Higashi-ku, Osaka City, Osaka Prefecture Mita Industry Co., Ltd. (72) Yoshinobu Kawakami 1-2-2 Tamatsukuri, Higashi-ku, Osaka City, Osaka Prefecture No. 28 in Mita Industry Co., Ltd. (56) Reference JP-A-59-75269 (JP, A) JP-A-56-92545 (JP, A) JP-A-58-195851 (JP, A) JP-A-57 -177161 (JP, A) JP 58-179850 (JP, A) JP 55-85426 (JP, A)
Claims (1)
６×１０4Ω乃至7.2×１０5Ωの範囲にありかつ平均粒
径が３０乃至４５ミクロンの範囲にあるフェライト焼結
還元粒子から成る磁性キャリヤと、体積抵抗が１×１０
13Ω-cm以上の顕電性トナー粒子とから成ることを特徴
とする電子写真用二成分系現像剤。1. A ferrite sintered reduced particle having a dynamic magnetic brush resistance as a magnetic brush in the range of 6 × 10 4 Ω to 7.2 × 10 5 Ω and an average particle size in the range of 30 to 45 μm. Magnetic carrier and volume resistance 1 × 10
A two-component developer for electrophotography, which comprises electrophotographic toner particles of 13 Ω-cm or more.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59084000A JPH0629992B2 (en) | 1984-04-27 | 1984-04-27 | Two-component developer for electrophotography |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59084000A JPH0629992B2 (en) | 1984-04-27 | 1984-04-27 | Two-component developer for electrophotography |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60229033A JPS60229033A (en) | 1985-11-14 |
| JPH0629992B2 true JPH0629992B2 (en) | 1994-04-20 |
Family
ID=13818257
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP59084000A Expired - Lifetime JPH0629992B2 (en) | 1984-04-27 | 1984-04-27 | Two-component developer for electrophotography |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0629992B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6617088B2 (en) | 2000-05-22 | 2003-09-09 | Fuji Xerox Co., Ltd. | Developer and image forming method |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS632076A (en) * | 1986-06-23 | 1988-01-07 | Mita Ind Co Ltd | Two-component type developer for using ferrite carrier |
| JPH09171287A (en) * | 1995-12-20 | 1997-06-30 | Fuji Xerox Co Ltd | Image forming device |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5585426A (en) * | 1978-12-21 | 1980-06-27 | Tdk Corp | Magnetic powder for toner or ink and production thereof |
| JPS57177161A (en) * | 1981-04-24 | 1982-10-30 | Nec Corp | Developer for electrophotography |
| JPS58179850A (en) * | 1982-04-15 | 1983-10-21 | Hitachi Metals Ltd | Ferrite carrier for electrophotography |
| JPS58195851A (en) * | 1982-05-12 | 1983-11-15 | Olympus Optical Co Ltd | Dry two-component developer |
| JPS6238696A (en) * | 1985-08-14 | 1987-02-19 | Mitsubishi Electric Corp | Buzz simulator for television radio wave detector |
-
1984
- 1984-04-27 JP JP59084000A patent/JPH0629992B2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6617088B2 (en) | 2000-05-22 | 2003-09-09 | Fuji Xerox Co., Ltd. | Developer and image forming method |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS60229033A (en) | 1985-11-14 |
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