JP2017167311A - Core material for carrier, carrier, developer, and electrophotography development system - Google Patents
Core material for carrier, carrier, developer, and electrophotography development system Download PDFInfo
- Publication number
- JP2017167311A JP2017167311A JP2016052127A JP2016052127A JP2017167311A JP 2017167311 A JP2017167311 A JP 2017167311A JP 2016052127 A JP2016052127 A JP 2016052127A JP 2016052127 A JP2016052127 A JP 2016052127A JP 2017167311 A JP2017167311 A JP 2017167311A
- Authority
- JP
- Japan
- Prior art keywords
- carrier
- core material
- carrier core
- resin
- ferrite
- 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
- 239000011162 core material Substances 0.000 title claims abstract description 118
- 238000011161 development Methods 0.000 title claims description 10
- 229910000859 α-Fe Inorganic materials 0.000 claims abstract description 94
- 239000002245 particle Substances 0.000 claims abstract description 80
- 239000000945 filler Substances 0.000 claims abstract description 39
- 230000005415 magnetization Effects 0.000 claims abstract description 33
- 229920005989 resin Polymers 0.000 claims description 85
- 239000011347 resin Substances 0.000 claims description 85
- 239000011148 porous material Substances 0.000 claims description 36
- 239000003795 chemical substances by application Substances 0.000 claims description 33
- 230000005484 gravity Effects 0.000 claims description 23
- 239000000969 carrier Substances 0.000 claims description 10
- 239000011247 coating layer Substances 0.000 claims description 8
- 238000000921 elemental analysis Methods 0.000 claims description 5
- 230000035699 permeability Effects 0.000 claims description 3
- 239000011800 void material Substances 0.000 abstract description 3
- 238000000034 method Methods 0.000 description 29
- 238000000576 coating method Methods 0.000 description 28
- 238000011049 filling Methods 0.000 description 28
- 239000011248 coating agent Substances 0.000 description 26
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 20
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 18
- 238000005259 measurement Methods 0.000 description 18
- 229920002050 silicone resin Polymers 0.000 description 18
- 229920000178 Acrylic resin Polymers 0.000 description 14
- 239000004925 Acrylic resin Substances 0.000 description 14
- 238000002834 transmittance Methods 0.000 description 12
- 238000010304 firing Methods 0.000 description 11
- 238000002360 preparation method Methods 0.000 description 11
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 10
- 229910052753 mercury Inorganic materials 0.000 description 10
- 239000011324 bead Substances 0.000 description 8
- 239000006229 carbon black Substances 0.000 description 8
- 230000007547 defect Effects 0.000 description 8
- 238000010438 heat treatment Methods 0.000 description 8
- 238000004519 manufacturing process Methods 0.000 description 8
- 239000007787 solid Substances 0.000 description 8
- 230000007423 decrease Effects 0.000 description 7
- 238000010298 pulverizing process Methods 0.000 description 7
- 239000002994 raw material Substances 0.000 description 7
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 6
- 238000001035 drying Methods 0.000 description 6
- 239000000843 powder Substances 0.000 description 6
- 239000000047 product Substances 0.000 description 6
- 241000519995 Stachys sylvatica Species 0.000 description 5
- 239000011230 binding agent Substances 0.000 description 5
- 239000007822 coupling agent Substances 0.000 description 5
- 239000013078 crystal Substances 0.000 description 5
- 239000002270 dispersing agent Substances 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 239000006087 Silane Coupling Agent Substances 0.000 description 4
- 206010047642 Vitiligo Diseases 0.000 description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 239000011521 glass Substances 0.000 description 4
- 238000007654 immersion Methods 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 239000001301 oxygen Substances 0.000 description 4
- 229910052760 oxygen Inorganic materials 0.000 description 4
- 108091008695 photoreceptors Proteins 0.000 description 4
- FZHAPNGMFPVSLP-UHFFFAOYSA-N silanamine Chemical compound [SiH3]N FZHAPNGMFPVSLP-UHFFFAOYSA-N 0.000 description 4
- 238000003756 stirring Methods 0.000 description 4
- 239000006228 supernatant Substances 0.000 description 4
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 3
- 239000004962 Polyamide-imide Substances 0.000 description 3
- 229920000180 alkyd Polymers 0.000 description 3
- 239000012298 atmosphere Substances 0.000 description 3
- 238000001354 calcination Methods 0.000 description 3
- 239000003054 catalyst Substances 0.000 description 3
- 238000011109 contamination Methods 0.000 description 3
- 238000013461 design Methods 0.000 description 3
- 229910001882 dioxygen Inorganic materials 0.000 description 3
- 239000003822 epoxy resin Substances 0.000 description 3
- 238000000227 grinding Methods 0.000 description 3
- 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 3
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 3
- 238000002156 mixing Methods 0.000 description 3
- 229920006122 polyamide resin Polymers 0.000 description 3
- 229920002312 polyamide-imide Polymers 0.000 description 3
- 229920000647 polyepoxide Polymers 0.000 description 3
- 229920001225 polyester resin Polymers 0.000 description 3
- 239000004645 polyester resin Substances 0.000 description 3
- 238000007639 printing Methods 0.000 description 3
- 229910000077 silane Inorganic materials 0.000 description 3
- 229910001220 stainless steel Inorganic materials 0.000 description 3
- 239000010935 stainless steel Substances 0.000 description 3
- WYTZZXDRDKSJID-UHFFFAOYSA-N (3-aminopropyl)triethoxysilane Chemical compound CCO[Si](OCC)(OCC)CCCN WYTZZXDRDKSJID-UHFFFAOYSA-N 0.000 description 2
- NOGBEXBVDOCGDB-NRFIWDAESA-L (z)-4-ethoxy-4-oxobut-2-en-2-olate;propan-2-olate;titanium(4+) Chemical compound [Ti+4].CC(C)[O-].CC(C)[O-].CCOC(=O)\C=C(\C)[O-].CCOC(=O)\C=C(\C)[O-] NOGBEXBVDOCGDB-NRFIWDAESA-L 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 238000000862 absorption spectrum Methods 0.000 description 2
- 239000002775 capsule Substances 0.000 description 2
- 239000011362 coarse particle Substances 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 238000007872 degassing Methods 0.000 description 2
- 239000000975 dye Substances 0.000 description 2
- 210000005069 ears Anatomy 0.000 description 2
- 230000005684 electric field Effects 0.000 description 2
- 238000011156 evaluation Methods 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 230000004907 flux Effects 0.000 description 2
- 239000007903 gelatin capsule Substances 0.000 description 2
- 230000009477 glass transition Effects 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 239000010410 layer Substances 0.000 description 2
- 239000006148 magnetic separator Substances 0.000 description 2
- 238000012423 maintenance Methods 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 239000008188 pellet Substances 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 239000000700 radioactive tracer Substances 0.000 description 2
- 230000000630 rising effect Effects 0.000 description 2
- -1 silane compound Chemical class 0.000 description 2
- 239000002002 slurry Substances 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 239000007921 spray Substances 0.000 description 2
- 238000001694 spray drying Methods 0.000 description 2
- 229920002803 thermoplastic polyurethane Polymers 0.000 description 2
- 239000010936 titanium Substances 0.000 description 2
- 229910052719 titanium Inorganic materials 0.000 description 2
- BPSIOYPQMFLKFR-UHFFFAOYSA-N trimethoxy-[3-(oxiran-2-ylmethoxy)propyl]silane Chemical compound CO[Si](OC)(OC)CCCOCC1CO1 BPSIOYPQMFLKFR-UHFFFAOYSA-N 0.000 description 2
- 229910052725 zinc Inorganic materials 0.000 description 2
- 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
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 229920000877 Melamine resin Polymers 0.000 description 1
- 229920000297 Rayon Polymers 0.000 description 1
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 description 1
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 229920001807 Urea-formaldehyde Polymers 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 238000004220 aggregation Methods 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 239000012876 carrier material Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000006837 decompression Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 229910001385 heavy metal Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- BDAGIHXWWSANSR-NJFSPNSNSA-N hydroxyformaldehyde Chemical compound O[14CH]=O BDAGIHXWWSANSR-NJFSPNSNSA-N 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 239000007788 liquid Substances 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
- VTHJTEIRLNZDEV-UHFFFAOYSA-L magnesium dihydroxide Chemical compound [OH-].[OH-].[Mg+2] VTHJTEIRLNZDEV-UHFFFAOYSA-L 0.000 description 1
- 229910001862 magnesium hydroxide Inorganic materials 0.000 description 1
- 239000000347 magnesium hydroxide Substances 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 238000007885 magnetic separation Methods 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- AMWRITDGCCNYAT-UHFFFAOYSA-L manganese oxide Inorganic materials [Mn].O[Mn]=O.O[Mn]=O AMWRITDGCCNYAT-UHFFFAOYSA-L 0.000 description 1
- KVGMATYUUPJFQL-UHFFFAOYSA-N manganese(2+) oxygen(2-) Chemical compound [O--].[O--].[O--].[O--].[Mn++].[Mn++].[Mn++] KVGMATYUUPJFQL-UHFFFAOYSA-N 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
- 238000000465 moulding Methods 0.000 description 1
- 230000006855 networking Effects 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 125000002524 organometallic group Chemical group 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000005011 phenolic resin Substances 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
- 239000011164 primary particle Substances 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 150000003242 quaternary ammonium salts Chemical class 0.000 description 1
- 238000004062 sedimentation Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 230000003595 spectral effect Effects 0.000 description 1
- 238000010186 staining Methods 0.000 description 1
- 229910052712 strontium Inorganic materials 0.000 description 1
- 229910000018 strontium carbonate Inorganic materials 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 229920001187 thermosetting polymer Polymers 0.000 description 1
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 description 1
- 229910001887 tin oxide Inorganic materials 0.000 description 1
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 229920006337 unsaturated polyester resin Polymers 0.000 description 1
- 230000004304 visual acuity Effects 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Landscapes
- Developing Agents For Electrophotography (AREA)
Abstract
Description
本発明は、キャリア用芯材、キャリア、該キャリアを含む現像剤、及び該現像剤を使用した電子写真現像システムに関する。 The present invention relates to a carrier core material, a carrier, a developer containing the carrier, and an electrophotographic development system using the developer.
電子写真現像方法は、現像剤中のトナー粒子を感光体上に形成された静電潜像に付着させて現像する方法であり、この方法で使用される現像剤は、トナー粒子とキャリア粒子からなる二成分系現像剤と、トナー粒子のみを用いる一成分系現像剤とに分けられる。 The electrophotographic development method is a method in which toner particles in a developer are attached to an electrostatic latent image formed on a photoreceptor and developed, and the developer used in this method is composed of toner particles and carrier particles. The two-component developer and the one-component developer using only toner particles.
こうした現像剤のうち、トナー粒子とキャリア粒子からなる二成分系現像剤を用いた現像方法としては、古くはカスケード法等が採用されていたが、現在では、マグネットロールを用いる磁気ブラシ法が主流である。二成分系現像剤において、キャリア粒子は、現像剤が充填されている現像ボックス内において、トナー粒子と共に攪拌されることによって、トナー粒子に所望の電荷を付与し、さらにこのように電荷を帯びたトナー粒子を感光体の表面に搬送して感光体上にトナー像を形成するための担体物質である。マグネットを保持する現像ロール上に残ったキャリア粒子は、この現像ロールから再び現像ボックス内に戻り、新たなトナー粒子と混合・攪拌され、一定期間繰り返して使用される。 Among these developers, as a developing method using a two-component developer composed of toner particles and carrier particles, the cascade method has been used in the past, but at present, the magnetic brush method using a magnet roll is the mainstream. It is. In the two-component developer, the carrier particles are agitated together with the toner particles in the developing box filled with the developer, thereby imparting a desired charge to the toner particles, and thus being charged. A carrier material for transporting toner particles to the surface of the photoreceptor to form a toner image on the photoreceptor. The carrier particles remaining on the developing roll holding the magnet are returned to the developing box from the developing roll, mixed and stirred with new toner particles, and used repeatedly for a certain period.
二成分系現像剤は、一成分系現像剤とは異なり、キャリア粒子はトナー粒子と混合及び攪拌され、トナー粒子を帯電させ、さらに搬送する機能を有しており、現像剤を設計する際の制御性が良い。したがって、二成分系現像剤は、高画質が要求されるフルカラー現像装置、画像維持の信頼性及び耐久性が要求される高速印刷を行う装置等に適している。このようにして用いられる二成分系現像剤においては、画像濃度、カブリ、白斑、階調性、解像力等の画像特性が、初期の段階から所定の値を示し、しかもこれらの特性が耐刷期間中に変動せず、安定に維持されることが必要である。これらの特性を安定に維持するためには、二成分系現像剤中に含有されるキャリア粒子の特性が安定していることが必要になる。二成分系現像剤を形成するキャリア粒子としては、従来、鉄粉キャリア、フェライトキャリア、樹脂被覆フェライトキャリア、磁性粉分散型樹脂キャリア等の各種キャリアが使用されていた。 Unlike the one-component developer, the two-component developer has a function of mixing and stirring the carrier particles with the toner particles, charging the toner particles, and further transporting the toner particles. Good controllability. Therefore, the two-component developer is suitable for a full-color developing device that requires high image quality, a device that performs high-speed printing that requires image maintenance reliability and durability, and the like. In the two-component developer used in this manner, image characteristics such as image density, fog, vitiligo, gradation, and resolving power show predetermined values from the initial stage, and these characteristics are in the printing life period. It needs to be kept stable without fluctuating inside. In order to maintain these characteristics stably, it is necessary that the characteristics of the carrier particles contained in the two-component developer are stable. Conventionally, various carriers such as an iron powder carrier, a ferrite carrier, a resin-coated ferrite carrier, and a magnetic powder-dispersed resin carrier have been used as carrier particles forming the two-component developer.
最近、オフィスのネットワーク化が進み、単機能の複写機から複合機への時代に進化している。また、サービス体制も、契約した保守作業員が定期的にメンテナンスを行って現像剤等を交換するようなシステムから、メンテナンスフリーシステムの時代へシフトしてきており、市場からは、現像剤の更なる長寿命化に対する要求が一層高まってきている。このような中で、キャリア粒子の軽量化を図り、現像剤寿命を伸ばすことを目的として、多孔質フェライト粒子を用いたフェライトキャリア芯材の空隙に樹脂を充填した樹脂充填型フェライトキャリアが提案されている。 Recently, the networking of offices has progressed, and it has evolved into an era from a single-function copying machine to a multifunction machine. In addition, the service system has shifted from a system in which contracted maintenance workers regularly maintain and replace developers to a era of maintenance-free systems. There is a growing demand for longer life. Under such circumstances, a resin-filled ferrite carrier in which a resin is filled in the voids of a ferrite carrier core material using porous ferrite particles has been proposed for the purpose of reducing the weight of the carrier particles and extending the developer life. ing.
例えば、特許文献１（特開２０１４−１９７０４０号公報）には、平均圧縮強度が１００ｍＮ以上、圧縮強度の変動係数が５０％以下である多孔質フェライト粒子からなる電子写真現像剤用樹脂充填型フェライトキャリア芯材や、該フェライトキャリア芯材の空隙に樹脂を充填した電子写真現像剤用樹脂充填型フェライトキャリアが提案され、該フェライトキャリアによれば、低比重で軽量化が図れ、かつ高い強度を有するため、耐久性に優れ長寿命化が達成できる等の効果があるとされている。 For example, Patent Document 1 (Japanese Patent Laid-Open No. 2014-197040) discloses a resin-filled ferrite for electrophotographic developer comprising porous ferrite particles having an average compressive strength of 100 mN or more and a coefficient of variation of compressive strength of 50% or less. A resin-filled ferrite carrier for an electrophotographic developer in which a resin is filled in a void in the carrier core material and the ferrite carrier core material has been proposed. According to the ferrite carrier, the weight can be reduced with a low specific gravity and high strength can be achieved. Therefore, it is said that there are effects such as excellent durability and long life.
また、特許文献２（特開２０１５−１９７４９０号公報）には、フェライトキャリア芯材として用いられる多孔質フェライト粒子の空隙にシリコーン樹脂を充填した電子写真現像剤用樹脂充填型フェライトキャリアであって、該シリコーン樹脂を充填した該多孔質フェライト粒子の真比重（Ｙ）と蛍光Ｘ線元素分析によって測定されたＳｉ／Ｆｅ値（Ｘ）とが特定の関係式を満たす電子写真現像剤用樹脂充填型フェライトキャリアが提案されており、該フェライトキャリアによれば、現像剤としたときに高い帯電量安定性を有し、また真比重を任意に制御できる等の効果があるとされている。 Patent Document 2 (Japanese Patent Laid-Open No. 2015-197490) discloses a resin-filled ferrite carrier for an electrophotographic developer in which voids of porous ferrite particles used as a ferrite carrier core material are filled with a silicone resin, Resin-filled type for electrophotographic developer in which the true specific gravity (Y) of the porous ferrite particles filled with the silicone resin and the Si / Fe value (X) measured by fluorescent X-ray elemental analysis satisfy a specific relational expression A ferrite carrier has been proposed. According to the ferrite carrier, when it is used as a developer, it has high charge amount stability, and is capable of controlling the true specific gravity arbitrarily.
このような樹脂充填型フェライトキャリアは軽量化が図れるため、耐久性に優れ、好都合である。しかしながら、樹脂充填型フェライトキャリアは、樹脂等の非磁性成分を含むため、全体として磁力が弱くなり、現像中にマグネットロールからキャリアが感光体へ飛散する、いわゆるキャリア飛散が起こりやすくなる。したがって、キャリアの飽和磁化を高め、磁力を強くすることが考えられる。例えば、特許文献１の実施例５において、多孔質フェライト粒子（フェライトキャリア芯材）作製時の焼成温度や酸素濃度を調整して、飽和磁化６６Ａｍ２／ｋｇのフェライトキャリアを作製することが開示されている。しかしながら、一般にフェライトの飽和磁化と電気抵抗はトレードオフの関係にあるため、単に飽和磁化を高めただけのキャリアは、その電気抵抗が低くなり、その結果、キャリア電流が高くなり、リーク現象や白斑といった画像不良が起こる恐れがある。したがって、キャリアの飽和磁化を高めるだけでなく、その電気抵抗が適切となるように制御することが望ましい。 Since such a resin-filled ferrite carrier can be reduced in weight, it is excellent in durability and convenient. However, since the resin-filled ferrite carrier contains a non-magnetic component such as a resin, the magnetic force as a whole is weakened, and so-called carrier scattering, in which the carrier is scattered from the magnet roll to the photoreceptor during development, is likely to occur. Therefore, it is conceivable to increase the saturation magnetization of the carrier and increase the magnetic force. For example, in Example 5 of Patent Document 1, it is disclosed that a ferrite carrier having a saturation magnetization of 66 Am 2 / kg is prepared by adjusting the firing temperature and oxygen concentration at the time of producing porous ferrite particles (ferrite carrier core material). ing. However, in general, the saturation magnetization and electrical resistance of ferrite are in a trade-off relationship. Therefore, a carrier that simply increases the saturation magnetization has a low electrical resistance, resulting in a high carrier current, a leakage phenomenon, and white spots. There is a risk of such image defects. Therefore, it is desirable not only to increase the saturation magnetization of the carriers but also to control the electrical resistance to be appropriate.
一方、樹脂充填型フェライトキャリアの表面に被覆樹脂を設けて、キャリアの特性を制御することが考えられる。例えば、特許文献１の実施例１において、多孔質フェライト粒子の空隙にメチルシリコーン樹脂を充填し、更にその表面に導電性制御剤としてのカーボンブラックを加えたアクリル樹脂を被覆することが開示されている。しかしながら、キャリアの製造上、被覆樹脂をばらつきなく均一に設けることは難しく、被覆樹脂のみでキャリアの電気抵抗を制御することは困難であると予想される。また、現像時にトナーと混合する際、被覆樹脂が若干なりとも剥がれてトナーに付着することがあるが、キャリアの電気抵抗を制御するために被覆樹脂にカーボンブラック等を多量に添加すると、この剥がれた被覆樹脂が濃く着色されたものとなるため、トナーに色移りする、いわゆる色よごれが発生する恐れがある。 On the other hand, it is conceivable to provide a coating resin on the surface of the resin-filled ferrite carrier to control the characteristics of the carrier. For example, in Example 1 of Patent Document 1, it is disclosed to fill a void of porous ferrite particles with a methyl silicone resin and coat an acrylic resin with carbon black as a conductivity control agent on the surface thereof. Yes. However, in manufacturing the carrier, it is difficult to uniformly provide the coating resin without variation, and it is expected that it is difficult to control the electric resistance of the carrier only with the coating resin. In addition, when mixed with toner during development, the coating resin may be peeled off to a small extent and adhere to the toner. However, if a large amount of carbon black or the like is added to the coating resin in order to control the electrical resistance of the carrier, this peeling will occur. Since the coated resin becomes deeply colored, there is a risk of so-called color stains that transfer to the toner.
本発明者らは、今般、樹脂充填型フェライトキャリアにおいて、キャリア用芯材の充填材の設計を制御することが、電気抵抗を適切なものとする上で重要であるとの知見を得た。具体的には、キャリア用芯材の飽和磁化として特定の範囲を選択し、かつ、フェライトキャリア芯材の電気抵抗とキャリア用芯材の電気抵抗との特定の関係を満足させることにより、高い飽和磁化を有するキャリアであっても、その電気抵抗を適切なものとすることができ、その結果、軽量で耐久性に優れるとともに、キャリア飛散が少なく、良好な画像が実現されるとの知見を得た。 The inventors of the present invention have recently found that it is important to control the design of the filler of the core material for the carrier in the resin-filled ferrite carrier in order to make the electric resistance appropriate. Specifically, high saturation is achieved by selecting a specific range for the saturation magnetization of the carrier core material and satisfying a specific relationship between the electrical resistance of the ferrite carrier core material and the electrical resistance of the carrier core material. Even if it is a carrier with magnetization, its electrical resistance can be made appropriate, and as a result, it has gained knowledge that it is light and excellent in durability, has less carrier scattering, and realizes a good image. It was.
したがって、本発明の目的は、軽量で耐久性に優れるとともに、キャリア飛散が少なく、良好な画像が実現される、キャリア用芯材を提供することにある。また、本発明の他の目的は、そのようなキャリア用芯材を備えたキャリアを提供することにある。 Accordingly, an object of the present invention is to provide a carrier core material that is lightweight and excellent in durability, has less carrier scattering, and realizes a good image. Another object of the present invention is to provide a carrier having such a carrier core material.
本発明の一態様によれば、多孔質フェライト粒子からなるフェライトキャリア芯材と、該フェライトキャリア芯材の空隙に充填された非磁性成分からなる充填材とを含むキャリア用芯材であって、
該キャリア用芯材の飽和磁化が６３〜９０Ａ・ｍ２／ｋｇであり、かつ、前記フェライトキャリア芯材の電気抵抗Ａ及びキャリア用芯材の電気抵抗Ｂが、下記式：
−１．０≦Ｌｏｇ１０（Ｂ／Ａ）≦０．７
を満足する、キャリア用芯材が提供される。
According to one aspect of the present invention, a carrier core material comprising a ferrite carrier core material composed of porous ferrite particles, and a filler composed of a nonmagnetic component filled in the voids of the ferrite carrier core material,
The saturation magnetization of the carrier core material is 63 to 90 A · m 2 / kg, and the electrical resistance A of the ferrite carrier core material and the electrical resistance B of the carrier core material are expressed by the following formula:
−1.0 ≦ Log 10 (B / A) ≦ 0.7
A carrier core material satisfying the above is provided.
本発明の他の一態様によれば、前記キャリア用芯材と、前記キャリア用芯材の表面に設けられた樹脂からなる被覆層を備えたキャリアであって、該キャリアの真比重が３．５〜４．５、飽和磁化が６３〜９０Ａ・ｍ２／ｋｇである、キャリアが提供される。 According to another aspect of the present invention, there is provided a carrier comprising the carrier core material and a coating layer made of a resin provided on the surface of the carrier core material, wherein the true specific gravity of the carrier is 3. A carrier is provided that has a saturation magnetization of 5 to 4.5 and a saturation magnetization of 63 to 90 A · m 2 / kg.
本発明の別の一態様によれば、前記キャリアと、トナーとを含む、現像剤が提供される。 According to another aspect of the present invention, a developer including the carrier and a toner is provided.
本発明の更なる別の一態様によれば、前記現像剤を使用した、電子写真現像システムが提供される。 According to yet another aspect of the present invention, there is provided an electrophotographic development system using the developer.
キャリア用芯材
本発明のキャリア用芯材は、多孔質フェライト粒子からなるフェライトキャリア芯材と、該フェライトキャリア芯材の空隙に充填された非磁性成分からなる充填材とを含む。このキャリア用芯材は、フェライトキャリア芯材の空隙に非磁性成分が充填された構造を有するため、軽量化が図れ、耐久性が向上し、長寿命となる。
Carrier Core Material The carrier core material of the present invention includes a ferrite carrier core material made of porous ferrite particles and a filler made of a nonmagnetic component filled in the voids of the ferrite carrier core material. Since this carrier core material has a structure in which the gap of the ferrite carrier core material is filled with a nonmagnetic component, the weight can be reduced, the durability can be improved, and the life can be extended.
また、本発明のキャリア用芯材は、その飽和磁化が適度に高いという特徴を有している。具体的には、このキャリア用芯材は、６３〜９０Ａ・ｍ２／ｋｇの飽和磁化を有する。このようなキャリア用芯材によれば、適度に高い飽和磁化を有するによりキャリア飛散を抑制することが可能となる。飽和磁化が６３Ａ・ｍ２／ｋｇ未満であると、キャリア飛散の原因となりやすく、９０Ａ・ｍ２／ｋｇを超えると、磁気ブラシの穂が硬くなり、良好な画質を得ることが難しくなる。飽和磁化は好ましくは６３〜７５Ａ・ｍ２／ｋｇであり、特に好ましくは６５〜７０Ａ・ｍ２／ｋｇである。 The carrier core material of the present invention has a feature that the saturation magnetization is moderately high. Specifically, the carrier core material has a saturation magnetization of 63 to 90 A · m 2 / kg. According to such a carrier core material, carrier scattering can be suppressed by having a reasonably high saturation magnetization. If the saturation magnetization is less than 63 A · m 2 / kg, carrier scattering is likely to occur, and if it exceeds 90 A · m 2 / kg, the ears of the magnetic brush become hard and it becomes difficult to obtain good image quality. The saturation magnetization is preferably 63 to 75 A · m 2 / kg, particularly preferably 65 to 70 A · m 2 / kg.
飽和磁化は、例えば、積分型Ｂ−Ｈトレーサー（株式会社理研電子製、ＢＨＵ−６０型）を使用して測定することができる。この場合、電磁石間に磁場測定用Ｈコイル及び磁化測定用４πＩコイルを入れ、試料を４πＩコイルに入れる。電磁石の電流を変化させ磁場Ｈを変化させたＨコイル及び４πＩコイルの出力をそれぞれ積分し、Ｈ出力をＸ軸に、４πＩコイルの出力をＹ軸にとって、ヒステリシスループを記録紙に描く。ここで測定条件としては、試料充填量：約１ｇ、試料充填セル：内径７ｍｍφ±０．０２ｍｍ、高さ１０ｍｍ±０．１ｍｍ、４πＩコイル：巻数３０回とすることができる。 The saturation magnetization can be measured using, for example, an integral BH tracer (manufactured by Riken Electronics Co., Ltd., BHU-60 type). In this case, a magnetic field measuring H coil and a magnetization measuring 4πI coil are placed between the electromagnets, and a sample is placed in the 4πI coil. The hysteresis coil is drawn on the recording paper by integrating the outputs of the H coil and the 4πI coil whose magnetic field H is changed by changing the current of the electromagnet, using the H output as the X axis and the 4πI coil as the Y axis. Here, the measurement conditions can be: sample filling amount: about 1 g, sample filling cell: inner diameter 7 mmφ ± 0.02 mm, height 10 mm ± 0.1 mm, 4πI coil: 30 turns.
その上、本発明のキャリア用芯材は、フェライトキャリア芯材の電気抵抗Ａ及びキャリア用芯材の電気抵抗Ｂが、式：−１．０≦Ｌｏｇ１０（Ｂ／Ａ）≦０．７を満足するものである。このようなキャリア用芯材によれば、リーク現象や白斑といった画像不良を抑制することが可能となる。Ｌｏｇ１０（Ｂ／Ａ）が−１．０未満であると、キャリア電流が高くなり過ぎて、リーク現象や白斑等の画像不良が発生しやすくなる。一方、Ｌｏｇ１０（Ｂ／Ａ）が０．７を超えると、キャリア電流が低くなり過ぎて、十分な画像濃度を得にくくなる。好ましくは、式：−０．３≦Ｌｏｇ１０（Ｂ／Ａ）≦０．７、特に好ましくは、式：−０．２≦Ｌｏｇ１０（Ｂ／Ａ）≦０．７を満足する。一方、上述の特許文献１に開示されるように、樹脂を充填したフェライトキャリア芯材（キャリア用芯材）の表面に導電性制御剤を加えた被覆樹脂を設けたキャリアとすることで、キャリアの電気抵抗及びキャリア電流を制御し、それによりリーク現象や白斑といった画像不良を抑制することや、画像濃度を調整することが考えられるが、このようなキャリアは、その被覆樹脂が多量に導電性制御剤を含むものとなるため透過度が低下したり、飽和磁化が低下したりするため、たとえその電気抵抗及びキャリア電流を制御したとしても、色よごれやキャリア飛散の問題を解消することが困難である。これに対し、本発明のキャリア用芯材は、キャリア用芯材自体の電気抵抗を制御することを特長としているため、キャリアとしたときの色よごれやキャリア飛散の問題を抑制しながらも、キャリアの電気抵抗やキャリア電流を適切に制御でき、その結果、リーク現象や白斑といった画像不良を抑制し、かつ所望の画像濃度を得ることが可能になる。 Moreover, in the carrier core material of the present invention, the electrical resistance A of the ferrite carrier core material and the electrical resistance B of the carrier core material satisfy the formula: −1.0 ≦ Log 10 (B / A) ≦ 0.7. Satisfied. According to such a carrier core material, it is possible to suppress image defects such as a leak phenomenon and white spots. When Log 10 (B / A) is less than −1.0, the carrier current becomes too high, and image defects such as a leak phenomenon and white spots tend to occur. On the other hand, when Log 10 (B / A) exceeds 0.7, the carrier current becomes too low and it becomes difficult to obtain a sufficient image density. Preferably, the formula: −0.3 ≦ Log 10 (B / A) ≦ 0.7, and particularly preferably, the formula: −0.2 ≦ Log 10 (B / A) ≦ 0.7 is satisfied. On the other hand, as disclosed in Patent Document 1 described above, a carrier in which a coating resin obtained by adding a conductive control agent to the surface of a ferrite carrier core material (carrier core material) filled with a resin is provided. It is conceivable to control the electrical resistance and carrier current, thereby suppressing image defects such as leakage phenomenon and white spots, and adjusting the image density. Because it contains a control agent, the transmittance decreases and the saturation magnetization decreases, so even if the electrical resistance and carrier current are controlled, it is difficult to solve the problem of color contamination and carrier scattering. It is. On the other hand, the carrier core material of the present invention is characterized by controlling the electrical resistance of the carrier core material itself, so that while preventing problems of color contamination and carrier scattering when used as a carrier, the carrier core material Thus, it is possible to appropriately control the electrical resistance and carrier current, and as a result, it is possible to suppress image defects such as a leak phenomenon and white spots and to obtain a desired image density.
電気抵抗Ａ及びＢは、例えば、次のようにして測定することができる。すなわち、磁極間間隔６．５ｍｍにてＮ極及びＳ極を対向させ、非磁性の平行平板電極（１０ｍｍ×４０ｍｍ）間に、試料２００ｍｇを秤量して挿入し、磁極（表面磁束密度：１５００Ｇａｕｓｓ、対向電極面積：１０ｍｍ×３０ｍｍ）を平行平板電極に付けることにより電極間に試料を保持させ、印加電圧２５０Ｖの抵抗を絶縁抵抗計にて測定する。 The electrical resistances A and B can be measured as follows, for example. That is, the N pole and the S pole are opposed to each other with a spacing of 6.5 mm between the magnetic poles, and 200 mg of a sample is weighed and inserted between the non-magnetic parallel plate electrodes (10 mm × 40 mm), and the magnetic poles (surface magnetic flux density: 1500 Gauss, A sample is held between the electrodes by attaching a counter electrode area (10 mm × 30 mm) to the parallel plate electrodes, and the resistance at an applied voltage of 250 V is measured with an insulation resistance meter.
本発明のキャリア用芯材は、その電気抵抗Ｂが、好ましくは、式：７．０≦Ｌｏｇ１０Ｂ≦９．０、特に好ましくは、式：７．０≦Ｌｏｇ１０Ｂ≦８．５を満足する。Ｌｏｇ１０Ｂを７．０以上とすることにより、白斑等の画像不良がより抑制され、９．０以下とすることにより、画像濃度がより良好なものとなる。 The carrier core material of the present invention preferably has an electrical resistance B of the formula: 7.0 ≦ Log 10 B ≦ 9.0, particularly preferably the formula: 7.0 ≦ Log 10 B ≦ 8.5. Satisfied. By setting Log 10 B to 7.0 or more, image defects such as vitiligo are further suppressed, and by setting it to 9.0 or less, the image density becomes better.
さらに、本発明のキャリア用芯材は、その真比重が、好ましくは３．７〜４．７、特に好ましくは３．９〜４．５である。真比重を３．７以上とすることにより、低比重すぎることによる帯電速度の低下がより抑制され、４．７以下とすることにより、低比重化の効果が十分なものとなり、十分な長寿命化が達成される。真比重は、ＪＩＳ Ｒ９３０１−２−１に準拠して、ピークメーターを用いて測定することができる。その際、溶媒としてメタノールを用い、温度２５℃で測定を行なうのが好ましい。 Furthermore, the carrier core material of the present invention has a true specific gravity of preferably 3.7 to 4.7, particularly preferably 3.9 to 4.5. By setting the true specific gravity to 3.7 or more, a decrease in charging speed due to excessively low specific gravity is further suppressed, and by setting the true specific gravity to 4.7 or less, the effect of reducing the specific gravity becomes sufficient, and a sufficiently long life is achieved. Is achieved. The true specific gravity can be measured using a peak meter in accordance with JIS R9301-2-1. At that time, it is preferable to perform the measurement at a temperature of 25 ° C. using methanol as a solvent.
＜フェライトキャリア芯材＞
フェライトキャリア芯材を構成する多孔質フェライト粒子は、その組成がＭｎ、Ｍｇ、Ｌｉ、Ｃａ、Ｓｒ、Ｃｕ、及びＺｎから選ばれる少なくとも１種を含むことが望ましい。近年の廃棄物規制を始めとする環境負荷低減の流れを考慮すると、Ｃｕ、Ｚｎ、Ｎｉ等の重金属を不可避不純物（随伴不純物）の範囲を超えて含まないことが好ましい。
<Ferrite carrier core material>
The porous ferrite particles constituting the ferrite carrier core material desirably include at least one selected from the group consisting of Mn, Mg, Li, Ca, Sr, Cu, and Zn. Considering the recent trend of reducing environmental loads including waste regulations, it is preferable not to include heavy metals such as Cu, Zn, and Ni beyond the range of inevitable impurities (accompanying impurities).
多孔質フェライト粒子は、その飽和磁化が、好ましくは６５〜９３Ａ・ｍ２／ｋｇ、特に好ましくは６５〜７８Ａ・ｍ２／ｋｇである。飽和磁化を上述の範囲内とすることにより、樹脂充填後のキャリア用芯材の飽和磁化がより適切に制御される。 The porous ferrite particles have a saturation magnetization of preferably 65 to 93 A · m 2 / kg, particularly preferably 65 to 78 A · m 2 / kg. By setting the saturation magnetization within the above-described range, the saturation magnetization of the carrier core material after resin filling is more appropriately controlled.
また、多孔質フェライト粒子は、その細孔容積が、好ましくは１５〜１００ｍｍ３／ｇ、特に好ましくは４０〜８０ｍｍ３／ｇである。細孔容積が１５ｍｍ３／ｇ以上であると、十分な量の樹脂を充填することができ、より軽量化を図ることができ、１００ｍｍ３／ｇ以下であると、キャリアの強度をより適切に保つことが可能となる。 Further, the porous ferrite particles have a pore volume of preferably 15 to 100 mm 3 / g, particularly preferably 40 to 80 mm 3 / g. When the pore volume is 15 mm 3 / g or more, a sufficient amount of resin can be filled, and the weight can be further reduced. When the pore volume is 100 mm 3 / g or less, the strength of the carrier is more appropriately increased. It becomes possible to keep.
所望の真比重となるように、上記細孔容積の範囲の中から適切な細孔容積を選択することができる。真比重の小さいキャリア用芯材を得るためには、細孔容積が大きいものに多めの樹脂を充填すればよく、真比重の大きいキャリア用芯材を得るためには、細孔容積が小さいものに少なめの樹脂を充填すればよい。 An appropriate pore volume can be selected from the pore volume range so as to obtain a desired true specific gravity. In order to obtain a carrier core material having a small true specific gravity, it is sufficient to fill a large pore volume with a large amount of resin, and in order to obtain a carrier core material having a large true specific gravity, a material having a small pore volume. It is sufficient to fill a small amount of resin.
さらに、多孔質フェライト粒子は、そのピーク細孔径が好ましくは０．２〜１．５μｍ、特に好ましくは０．３〜１．０μｍである。ピーク細孔径が０．２μｍ以上であると、芯材表面の凹凸の大きさが適度な大きさとなるため、トナーとの接触面積が増加し、トナーとの摩擦帯電が効率よく行なわれるため、低比重でありなながら、帯電の立ち上がり特性が良好なものとなる。ピーク細孔径が１．５μｍ以下であると、凝集粒子や異形粒子の発生を抑制するとともに、キャリア粒子自体の割れが抑制され、帯電変動を防ぐことができる。 Furthermore, the porous ferrite particles preferably have a peak pore diameter of 0.2 to 1.5 μm, particularly preferably 0.3 to 1.0 μm. When the peak pore diameter is 0.2 μm or more, the unevenness on the surface of the core material becomes an appropriate size, the contact area with the toner increases, and the frictional charging with the toner is efficiently performed. Despite the specific gravity, the charge rising characteristics are good. When the peak pore diameter is 1.5 μm or less, the generation of aggregated particles and irregularly shaped particles can be suppressed, and the cracking of the carrier particles themselves can be suppressed, thereby preventing fluctuations in charging.
この多孔質フェライト粒子の細孔径及び細孔容積の測定は、例えば、水銀ポロシメーター（Ｔｈｅｒｍｏ Ｆｉｓｈｅｒ Ｓｃｉｅｎｔｉｆｉｃ社製、Ｐａｓｃａｌ１４０及びＰａｓｃａｌ２４０）を用いて測定することができる。その際、例えば、ディラトメーターはＣＤ３Ｐ（粉体用）を使用し、サンプルを複数の穴を開けた市販のゼラチン製カプセルに入れて、ディラトメーター内に入れる。Ｐａｓｃａｌ１４０で脱気後、水銀を充填し低圧領域（０〜４００Ｋｐａ）を測定し、１ｓｔ Ｒｕｎとする。次に再び脱気と低圧領域（０〜４００Ｋｐａ）の測定を行い、２ｎｄ Ｒｕｎとする。２ｎｄ Ｒｕｎの後、ディラトメーターと水銀とカプセルとサンプルを合わせた重量を測定する。次にＰａｓｃａｌ２４０で高圧領域（０．１Ｍｐａ〜２００Ｍｐａ）を測定する。この高圧部の測定で得られた水銀圧入量をもって、多孔質フェライト粒子の細孔容積及びピーク細孔径を求める。細孔径を求める際には水銀の表面張力を４８０ｄｙｎ／ｃｍ、接触角を１４１．３°として計算すればよい。 The pore diameter and pore volume of the porous ferrite particles can be measured using, for example, a mercury porosimeter (manufactured by Thermo Fisher Scientific, Pascal 140 and Pascal 240). In that case, for example, CD3P (for powder) is used as the dilatometer, and the sample is put in a commercially available gelatin capsule having a plurality of holes and placed in the dilatometer. After degassing with Pascal 140, it is filled with mercury, the low pressure region (0 to 400 Kpa) is measured, and 1st Run is obtained. Next, deaeration and measurement of the low pressure region (0 to 400 Kpa) are performed again to obtain 2nd Run. After 2nd Run, weigh the combined dilatometer, mercury, capsule and sample. Next, the high pressure region (0.1 Mpa to 200 Mpa) is measured with Pascal 240. The pore volume and the peak pore diameter of the porous ferrite particles are determined from the amount of mercury intrusion obtained by the measurement at the high pressure part. When determining the pore diameter, the surface tension of mercury may be calculated as 480 dyn / cm and the contact angle as 141.3 °.
多孔質フェライト粒子からなるフェライトキャリア芯材は、その電気抵抗Ａが、好ましくは、式：６．５≦Ｌｏｇ１０Ａ≦９．５、特に好ましくは、式：７．０Ｌｏｇ１０Ａ≦９．０を満足する。Ｌｏｇ１０Ａを６．５以上とすることにより、白斑等の画像不良がより抑制され、９．５以下とすることにより、画像濃度がより良好なものとなる。一方、上述したように、キャリア用芯材の表面に導電性制御剤を加えた被覆樹脂を設けたキャリアとすることで、キャリアの電気抵抗及びキャリア電流を制御することが考えられるが、このようなキャリアは色よごれやキャリア飛散の問題を解消することが困難である。これに対し、本発明のキャリア用芯材は、キャリア用芯材自体の電気抵抗を制御することを特長としているため、キャリアとしたときの色よごれやキャリア飛散の問題を抑制しながらも、キャリアの電気抵抗やキャリア電流を適切に制御することが可能になる。 The ferrite carrier core material composed of porous ferrite particles has an electric resistance A of preferably formula: 6.5 ≦ Log 10 A ≦ 9.5, and particularly preferably formula: 7.0 Log 10 A ≦ 9.0. Satisfied. By setting Log 10 A to 6.5 or more, image defects such as vitiligo are further suppressed, and by setting the Log 10 A to 9.5 or less, the image density becomes better. On the other hand, as described above, it is conceivable to control the electrical resistance and carrier current of the carrier by using a carrier provided with a coating resin to which a conductive control agent is added on the surface of the carrier core material. Such carriers are difficult to eliminate the problems of color stains and carrier scattering. On the other hand, the carrier core material of the present invention is characterized by controlling the electrical resistance of the carrier core material itself, so that while preventing problems of color contamination and carrier scattering when used as a carrier, the carrier core material It is possible to appropriately control the electrical resistance and carrier current of the semiconductor device.
＜充填材＞
フェライトキャリア芯材の空隙に充填される充填材は、非磁性成分であれば特に限定されない。典型的な非磁性成分は樹脂であり、好ましくはシロキサン結合を有するシリコーン樹脂である。シリコーン樹脂は、ストレートシリコーン樹脂及び変性シリコーン樹脂のいずれであってもよい。変性シリコーン樹脂の例としては、アクリル樹脂、ポリエステル樹脂、エポキシ樹脂、ポリアミド樹脂、ポリアミドイミド樹脂、アルキッド樹脂、ウレタン樹脂、フッ素樹脂等の各樹脂で変性したシリコーン樹脂等が挙げられる。また、非磁性成分として３−グリシドキシプロピルトリメトキシシランなどのシラン化合物またはその重合体を用いることもできる。本明細書において、シラン化合物やその重合体も樹脂と称するものとする。特に、シリコーン樹脂として室温硬化型のメチルシリコーン樹脂を用い、さらに有機チタン系触媒とアミノシランカップリング剤を含有するものが望ましい。有機チタン系触媒の例としてはチタンジイソプロポキシビス（エチルアセトアセテート）等が挙げられ、アミノシランカップリング剤の例としては３−アミノプロピルトリエトキシシシラン等が挙げられる。
<Filler>
The filler to be filled in the voids of the ferrite carrier core material is not particularly limited as long as it is a nonmagnetic component. A typical nonmagnetic component is a resin, preferably a silicone resin having a siloxane bond. The silicone resin may be either a straight silicone resin or a modified silicone resin. Examples of modified silicone resins include silicone resins modified with resins such as acrylic resins, polyester resins, epoxy resins, polyamide resins, polyamideimide resins, alkyd resins, urethane resins, and fluororesins. A silane compound such as 3-glycidoxypropyltrimethoxysilane or a polymer thereof can also be used as the nonmagnetic component. In this specification, a silane compound and a polymer thereof are also referred to as a resin. In particular, it is desirable to use a room temperature curable methyl silicone resin as the silicone resin and further contain an organotitanium catalyst and an aminosilane coupling agent. Examples of the organic titanium catalyst include titanium diisopropoxybis (ethyl acetoacetate), and examples of the aminosilane coupling agent include 3-aminopropyltriethoxysilane.
充填材の充填量は、フェライトキャリア芯材１００重量部に対して、固形分として、好ましくは０．５〜３５重量部、より好ましくは４〜２０重量部である。充填量を０．５重量部以上とすることにより、充填が十分なものとなり、被覆樹脂による帯電量の制御が容易となる。また、充填量を３５重量部以下とすることにより、充填時の凝集粒子発生が抑制され、帯電変動がより抑制される。 The filling amount of the filler is preferably 0.5 to 35 parts by weight, more preferably 4 to 20 parts by weight as a solid content with respect to 100 parts by weight of the ferrite carrier core material. By setting the filling amount to 0.5 parts by weight or more, the filling becomes sufficient, and the charge amount by the coating resin can be easily controlled. Further, by setting the filling amount to 35 parts by weight or less, the generation of aggregated particles at the time of filling is suppressed, and the charge fluctuation is further suppressed.
本発明のキャリア用芯材は、望ましくは充填材を構成する非磁性成分がシロキサン結合を有しており、かつ、蛍光Ｘ線元素分析によって測定されたキャリア用芯材のＳｉ／Ｆｅ値が、好ましくは０．００２〜０．０１５、特に好ましくは０．００４〜０．０１である。シロキサン結合を有する非磁性成分の例としては、シリコーン樹脂が挙げられる。ここで、Ｓｉ／Ｆｅ値は、シロキサン結合を有する充填材の充填性の指標となるものであり、Ｓｉ／Ｆｅ値を上述の範囲内とすることにより、充填性をより適切に制御することができ、キャリア用芯材の電気抵抗をより厳密に制御することが可能となる。蛍光Ｘ線元素分析は、キャリア用芯材表面から数μｍ付近存在する元素の量を測定する手法であり、これによりキャリア芯材表面近傍に存在する樹脂量を評価することができる。この測定は例えば、次のようにして行なうことができる。すなわち、蛍光Ｘ線元素分析装置（株式会社リガク製、ＺＳＸ１００ｓ）を用い、サンプル約５ｇを真空用粉末試料容器（株式会社リガク製、ＲＳ６４０）に入れ、試料フォルダにセットし、上記装置にて、ＳｉとＦｅの測定を行なう。ここで、測定条件としては、ＳｉについてはＳｉ−Ｋα線を測定線とし、管電圧５０ｋＶ、管電流５０ｍＡ、分光結晶にＰＥＴ、検出器としてＰＣ（プロポーショナルカウンター）を用いることができる。ＦｅについてはＦｅ−Ｋα線を測定線とし、管電圧５０ｋＶ、管電流５０ｍＡ、分光結晶にＬｉＦ、検出器としてＳＣ（シンチレーションカウンター）を用いることができる。得られたそれぞれの蛍光Ｘ線強度を用い、強度比（Ｓｉ強度／Ｆｅ強度）を計算して、Ｓｉ／Ｆｅ値とする。 In the carrier core material of the present invention, the nonmagnetic component constituting the filler preferably has a siloxane bond, and the Si / Fe value of the carrier core material measured by fluorescent X-ray elemental analysis is Preferably it is 0.002-0.015, Most preferably, it is 0.004-0.01. An example of a nonmagnetic component having a siloxane bond is a silicone resin. Here, the Si / Fe value is an index of the filling property of the filler having a siloxane bond, and the filling property can be more appropriately controlled by setting the Si / Fe value within the above-mentioned range. This makes it possible to more strictly control the electrical resistance of the carrier core material. The fluorescent X-ray elemental analysis is a technique for measuring the amount of an element present in the vicinity of several μm from the surface of the carrier core material, whereby the amount of resin present in the vicinity of the surface of the carrier core material can be evaluated. This measurement can be performed, for example, as follows. That is, using a fluorescent X-ray elemental analyzer (Rigaku Co., Ltd., ZSX100s), about 5 g of sample is put in a vacuum powder sample container (Rigaku Co., Ltd., RS640), set in a sample folder, Si and Fe are measured. Here, as measurement conditions, for Si, a Si—Kα line is used as a measurement line, a tube voltage of 50 kV, a tube current of 50 mA, PET as a spectral crystal, and a PC (proportional counter) as a detector can be used. For Fe, the Fe—Kα line is used as the measurement line, the tube voltage is 50 kV, the tube current is 50 mA, LiF is used as the spectroscopic crystal, and SC (scintillation counter) is used as the detector. Using each of the obtained fluorescent X-ray intensities, the intensity ratio (Si intensity / Fe intensity) is calculated to obtain the Si / Fe value.
本発明のキャリア用芯材は、その電気抵抗や帯電量、帯電速度をコントロールすることを目的に、充填材に導電性制御剤を含ませることが望ましい。充填材が導電性制御剤を含むことにより、キャリアの被覆樹脂に、透過度低下の恐れのある導電性制御剤を多量に含ませる必要が無くなり、その結果、透過度が充分に高く、かつ電気抵抗が適切に制御されたキャリアを得ることができる。導電性制御剤の添加量は、充填材の非磁性成分１００重量部に対して、好ましくは５〜３５重量部、特に好ましくは７〜２０重量部である。添加量を５重量部以上とすることにより、キャリア用芯材の電気抵抗をより適切に制御することが可能となり、またその結果、キャリアの被覆樹脂に透過度低下の恐れの有る導電性制御剤を多量に含ませる必要が無くなる。添加量を３５重量部以下とすることにより、急激な電流リークがより抑制される。導電性制御剤の例としては、導電性カーボンや、酸化チタン、酸化スズ等の酸化物、各種の有機系導電性制御剤が挙げられる。 In the carrier core material of the present invention, it is desirable to include a conductive control agent in the filler for the purpose of controlling the electrical resistance, charge amount, and charging speed. When the filler contains the conductivity control agent, it is not necessary to include a large amount of the conductivity control agent that may cause a decrease in the permeability in the coating resin of the carrier. A carrier with appropriately controlled resistance can be obtained. The addition amount of the conductivity control agent is preferably 5 to 35 parts by weight, particularly preferably 7 to 20 parts by weight, with respect to 100 parts by weight of the nonmagnetic component of the filler. By making the addition amount 5 parts by weight or more, it becomes possible to more appropriately control the electric resistance of the carrier core material, and as a result, there is a possibility that the conductivity of the coating resin of the carrier may be reduced. Need not be included in large quantities. By making the addition amount 35 parts by weight or less, rapid current leakage is further suppressed. Examples of the conductivity control agent include conductive carbon, oxides such as titanium oxide and tin oxide, and various organic conductivity control agents.
また、充填材中には、帯電制御剤を含有させることができる。帯電制御剤の例としては、トナー用に一般的に用いられる各種の帯電制御剤や、各種シランカップリング剤が挙げられる。これは多量の充填材を充填した場合、帯電付与能力が低下することがあるが、各種の帯電制御剤やシランカップリング剤を添加することにより、コントロールできるためである。使用できる帯電制御剤やカップリング剤の種類は特に限定されないが、ニグロシン系染料、４級アンモニウム塩、有機金属錯体、含金属モノアゾ染料等の帯電制御剤、アミノシランカップリング剤やフッ素系シランカップリング剤等が好ましい。 Moreover, the charge control agent can be contained in the filler. Examples of the charge control agent include various charge control agents generally used for toners and various silane coupling agents. This is because when a large amount of filler is filled, the charge imparting ability may be reduced, but it can be controlled by adding various charge control agents and silane coupling agents. The types of charge control agents and coupling agents that can be used are not particularly limited, but charge control agents such as nigrosine dyes, quaternary ammonium salts, organometallic complexes, and metal-containing monoazo dyes, aminosilane coupling agents, and fluorine-based silane couplings. An agent or the like is preferable.
このように、本発明のキャリア用芯材は、充填材の設計、特に充填材の充填量や充填材中の導電性制御剤量を適切に制御することにより、高い飽和磁化を有するものであっても、その電気抵抗を適切なものとすることが可能となる。その結果、軽量で耐久性に優れるとともに、キャリア飛散が少なく、良好な画像が実現されるキャリアを得ることができる。 As described above, the carrier core material of the present invention has high saturation magnetization by appropriately controlling the filler design, in particular, the filling amount of the filler and the amount of the conductive control agent in the filler. However, the electrical resistance can be made appropriate. As a result, it is possible to obtain a carrier that is lightweight and excellent in durability, has less carrier scattering, and realizes a good image.
また、従来の樹脂充填型フェライトキャリアは、これを製造する際に多孔質フェライト粒子の細孔容積が多少なりとも変動し、キャリアの電気抵抗が変動するという問題があるのに対し、本発明のキャリア用芯材は、充填材の設計、特に充填材の充填量や充填材中の導電性制御剤量を適切に制御することにより、多孔質フェライト粒子の細孔容積が多少変動しても、電気抵抗が変動しにくいという特長を有する。 In addition, the conventional resin-filled ferrite carrier has a problem that the pore volume of the porous ferrite particles fluctuates somewhat when manufacturing the same, and the electric resistance of the carrier fluctuates. Even if the pore volume of the porous ferrite particles is slightly changed by appropriately controlling the filler design, especially the filler filling amount and the amount of the conductive control agent in the filler, It has the feature that electric resistance is not easily changed.
キャリア
本発明のキャリアは、上記のキャリア用芯材と、キャリア用芯材の表面に設けられた樹脂からなる被覆層を備えたものである。キャリア特性、特に帯電特性を始めとする電気特性はキャリア表面に存在する材料や性状に影響されることが多い。したがって、適切な樹脂を表面被覆することによって、所望とするキャリア特性を、精度良く調整することができる。
Carrier The carrier of the present invention comprises the above carrier core material and a coating layer made of a resin provided on the surface of the carrier core material. Carrier characteristics, particularly electrical characteristics such as charging characteristics, are often affected by materials and properties existing on the carrier surface. Therefore, the desired carrier characteristics can be accurately adjusted by coating the surface with an appropriate resin.
本発明のキャリアは、３．５〜４．５の真比重を有する。真比重が３．５未満であると、低比重すぎるため、帯電速度が低下しすぎることがあり、また、４．５を超えると、低比重化の効果が得られず、超寿命化が達成できないことがある。真比重は、好ましくは３．７〜４．３、特に好ましくは３．８〜４．２である。 The carrier of the present invention has a true specific gravity of 3.5 to 4.5. If the true specific gravity is less than 3.5, the charging speed may be too low because the specific gravity is too low. If the true specific gravity is more than 4.5, the effect of reducing the specific gravity cannot be obtained and the life span is extended. There are things that cannot be done. The true specific gravity is preferably 3.7 to 4.3, and particularly preferably 3.8 to 4.2.
また、本発明のキャリアは、６３〜９０Ａ・ｍ２／ｋｇの飽和磁化を有する。飽和磁化が６３Ａ・ｍ２／ｋｇ未満であると、キャリア飛散の原因となりやすく、９０Ａ・ｍ２／ｋｇを超えると、磁気ブラシの穂が硬くなり、良好な画質を得ることが難しくなる。飽和磁化は好ましくは６３〜７５Ａ・ｍ２／ｋｇ、特に好ましくは６５〜７０Ａ・ｍ２／ｋｇである。 The carrier of the present invention has a saturation magnetization of 63 to 90 A · m 2 / kg. If the saturation magnetization is less than 63 A · m 2 / kg, carrier scattering is likely to occur, and if it exceeds 90 A · m 2 / kg, the ears of the magnetic brush become hard and it becomes difficult to obtain good image quality. The saturation magnetization is preferably 63 to 75 A · m 2 / kg, particularly preferably 65 to 70 A · m 2 / kg.
被覆樹脂は特に制限されない。被覆樹脂の例としては、フッ素樹脂、アクリル樹脂、エポキシ樹脂、ポリアミド樹脂、ポリアミドイミド樹脂、ポリエステル樹脂、不飽和ポリエステル樹脂、尿素樹脂、メラミン樹脂、アルキッド樹脂、フェノール樹脂、フッ素アクリル樹脂、アクリル−スチレン樹脂、シリコーン樹脂、及び変性シリコーン樹脂等が挙げられる。変性シリコーン樹脂の例としては、アクリル樹脂、ポリエステル樹脂、エポキシ樹脂、ポリアミド樹脂、ポリアミドイミド樹脂、アルキッド樹脂、ウレタン樹脂、フッ素樹脂等の各樹脂で変性したシリコーン樹脂等が挙げられる。使用中の機械的ストレスによる樹脂の脱離を考慮すると、熱硬化性樹脂が好ましく用いられる。好ましい樹脂はアクリル樹脂である。アクリル樹脂を表面被覆することによって、所望のキャリア特性を、精度良く調製することができる。樹脂の被覆量は、樹脂被覆前のキャリア１００重量部に対して、好ましくは０．５〜５．０重量部、特に好ましくは１．０〜３．０重量部である。 The coating resin is not particularly limited. Examples of coating resins include fluororesins, acrylic resins, epoxy resins, polyamide resins, polyamideimide resins, polyester resins, unsaturated polyester resins, urea resins, melamine resins, alkyd resins, phenol resins, fluoroacrylic resins, and acrylic-styrene. Examples thereof include resins, silicone resins, and modified silicone resins. Examples of modified silicone resins include silicone resins modified with resins such as acrylic resins, polyester resins, epoxy resins, polyamide resins, polyamideimide resins, alkyd resins, urethane resins, and fluororesins. In view of the detachment of the resin due to mechanical stress during use, a thermosetting resin is preferably used. A preferred resin is an acrylic resin. By covering the surface with an acrylic resin, desired carrier characteristics can be accurately prepared. The coating amount of the resin is preferably 0.5 to 5.0 parts by weight, particularly preferably 1.0 to 3.0 parts by weight with respect to 100 parts by weight of the carrier before resin coating.
このキャリアは、その被覆層が導電性制御剤を含むことができる。導電性制御剤の含有量は、被覆層の樹脂に対して、好ましくは０．３〜８．０重量％、特に好ましくは１．０〜６．０重量％である。含有量を０．３重量％以上とすることにより、キャリアの電気抵抗がより適切に制御され、８．０重量部以下とすることにより、キャリアの透過度低下がより抑制される。 The carrier layer of the carrier can contain a conductivity control agent. The content of the conductive control agent is preferably 0.3 to 8.0% by weight, particularly preferably 1.0 to 6.0% by weight, based on the resin of the coating layer. By setting the content to 0.3% by weight or more, the electric resistance of the carrier is more appropriately controlled, and by setting the content to 8.0 parts by weight or less, a decrease in carrier permeability is further suppressed.
また、被覆層の樹脂は、帯電制御剤を含有することができる。導電性制御剤や帯電制御剤の種類は、充填材の場合と同様である。 In addition, the resin of the coating layer can contain a charge control agent. The types of the conductivity control agent and the charge control agent are the same as in the case of the filler.
本発明のキャリアは、その透過度が、好ましくは９０％以上、特に好ましくは９５％以上である。透過度を９０％以上とすることにより、色よごれの問題がより抑制される。透過度の上限は特に限定はされず、１００％であってもよい。透過度は、例えば次のようにして測定することができる。すなわち、試料であるキャリア１５ｇと水２５ｇを５０ｃｃのガラス瓶に入れ、そのガラス瓶をボールミルにて１５０ｒｐｍで２０分攪拌した後、静置してから上澄み液を回収する。その後、回収した上澄み液の吸収スペクトルを分光光度計（島津製作所製、ＵＶ−１８００）にて測定し、５００ｎｍにおける透過率を測定し、その測定値を透過度とする。 The carrier of the present invention has a transmittance of preferably 90% or more, particularly preferably 95% or more. By setting the transmittance to 90% or more, the problem of color staining is further suppressed. The upper limit of the transmittance is not particularly limited, and may be 100%. The transmittance can be measured, for example, as follows. That is, 15 g of a carrier as a sample and 25 g of water are put into a 50 cc glass bottle, the glass bottle is stirred at 150 rpm for 20 minutes by a ball mill, and allowed to stand, and then the supernatant liquid is collected. Thereafter, the absorption spectrum of the collected supernatant is measured with a spectrophotometer (manufactured by Shimadzu Corporation, UV-1800), the transmittance at 500 nm is measured, and the measured value is taken as the transmittance.
さらに、本発明のキャリアは、そのキャリア電流が、好ましくは５〜５０μＡ以上、さらに好ましくは１０〜５０μＡ、特に好ましくは１０〜４０μＡである。キャリア電流を５０μＡ以下とすることにより、リーク現象や白斑といった画像不良がより抑制され、５μＡ以上とすることにより所望の画像濃度が得られる。キャリア電流は、例えば次のようにして測定することができる。すなわち、試料８００ｇを秤量し、温度２０〜２６℃、湿度５０〜６０％ＲＨの環境に１５分以上曝露した後、マグネットローラーとＡｌ素管を電極とし、その間隔を４．５ｍｍに配置した電流測定装置を用いて印可電圧５００Ｖにて測定する。 Furthermore, the carrier of the present invention has a carrier current of preferably 5 to 50 μA or more, more preferably 10 to 50 μA, and particularly preferably 10 to 40 μA. By setting the carrier current to 50 μA or less, image defects such as a leak phenomenon and vitiligo are further suppressed, and by setting the carrier current to 5 μA or more, a desired image density can be obtained. The carrier current can be measured, for example, as follows. That is, 800 g of a sample was weighed and exposed to an environment with a temperature of 20 to 26 ° C. and a humidity of 50 to 60% RH for 15 minutes or more, and then a current with a magnet roller and an Al base tube as an electrode and an interval of 4.5 mm. Measurement is performed at an applied voltage of 500 V using a measuring device.
現像剤
本発明の現像剤は、上記のキャリアと、トナーとを含むものである。トナー粒子には、粉砕法によって製造される粉砕トナー粒子と、重合法により製造される重合トナー粒子とがあるが、本発明ではいずれの方法により得られたトナー粒子も使用することができる。
Developer The developer of the present invention contains the above carrier and toner. The toner particles include pulverized toner particles produced by a pulverization method and polymerized toner particles produced by a polymerization method. In the present invention, toner particles obtained by any method can be used.
電子写真現像システム
本発明の電子写真現像システムは、上記の現像剤を使用したものである。電子写真現像システムは、有機光導電体層を有する潜像保持体に形成されている静電潜像を、バイアス電界を付与しながら、トナー及びキャリアを有する二成分現像剤の磁気ブラシによって反転現像する現像方式を用いたデジタル方式のコピー機、プリンター、ＦＡＸ、印刷機等を挙げることができる。また、磁気ブラシから静電潜像側に現像バイアスを印加する際に、ＤＣバイアスにＡＣバイアスを重畳する方法である交番電界を用いるフルカラー機等も挙げることができる。
Electrophotographic development system The electrophotographic development system of the present invention uses the developer described above. The electrophotographic development system reversely develops an electrostatic latent image formed on a latent image holding member having an organic photoconductive layer with a magnetic brush of a two-component developer having toner and carrier while applying a bias electric field. Examples thereof include a digital copying machine, a printer, a FAX, and a printing machine that use the developing method. In addition, a full-color machine using an alternating electric field, which is a method of superimposing an AC bias on a DC bias when a developing bias is applied from the magnetic brush to the electrostatic latent image side, can also be mentioned.
キャリア用芯材及びキャリアの製造方法
次に、本発明のキャリア用芯材及びキャリアの製造方法について説明する。
Next, the carrier core material and the carrier manufacturing method of the present invention will be described.
＜キャリア用芯材の製造＞
本発明のキャリア用芯材のフェライトキャリア芯材として用いられる多孔質フェライト粒子を製造するには、まず、原材料を適量秤量した後、ボールミル又は振動ミル等で０．５時間以上、好ましくは１〜２０時間粉砕混合する。原料は特に制限されない。
<Manufacture of core material for carrier>
In order to produce the porous ferrite particles used as the ferrite carrier core material of the carrier core material of the present invention, first, an appropriate amount of the raw material is weighed, and then 0.5 hours or more, preferably 1 to 3 with a ball mill or a vibration mill. Grind and mix for 20 hours. The raw material is not particularly limited.
このようにして得られた粉砕物は加圧成型機等を用いてペレット化した後、７００〜１２００℃の温度で仮焼成する。 The pulverized product thus obtained is pelletized using a pressure molding machine or the like, and then calcined at a temperature of 700 to 1200 ° C.
仮焼成後さらにボールミル又は振動ミル等で粉砕した後、水を加えてビーズミル等を用いて微粉砕を行う。次に必要に応じて分散剤、バインダー等を添加し、粘度調整後、スプレードライヤーにて粒状化し、造粒を行う。仮焼成後に粉砕する際は、水を加えて湿式ボールミルや湿式振動ミル等で粉砕してもよい。上記のボールミル、振動ミル、ビーズミル等の粉砕機は特に限定されないが、原料を効果的かつ均一に分散させるためには、使用するメディアに５ｍｍ以下の粒径を持つ微粒なビーズを使用することが好ましい。また使用するビーズの径、組成、粉砕時間を調整することによって、粉砕度合いをコントロールすることができる。 After calcination, the mixture is further pulverized by a ball mill or a vibration mill, and then water is added and fine pulverization is performed using a bead mill or the like. Next, if necessary, a dispersant, a binder, etc. are added, and after adjusting the viscosity, it is granulated with a spray dryer and granulated. When pulverizing after calcination, water may be added and pulverized with a wet ball mill, a wet vibration mill or the like. The above-mentioned ball mill, vibration mill, bead mill and other pulverizers are not particularly limited, but in order to disperse the raw materials effectively and uniformly, it is necessary to use fine beads having a particle size of 5 mm or less for the media to be used. preferable. Further, the degree of grinding can be controlled by adjusting the diameter, composition and grinding time of the beads used.
次いで、得られた造粒物を、４００〜８００℃で加熱し、添加した分散剤やバインダーといった有機成分の除去を行う。分散剤やバインダーが残ったまま本焼成を行うと、有機成分の分解、酸化によって本焼成装置内の酸素濃度が変動しやすく、磁気特性に大きく影響を与えるため、安定して製造することが困難である。また、これらの有機成分は多孔質性の制御、つまりフェライトの結晶成長を変動させる原因となる。 Next, the obtained granulated product is heated at 400 to 800 ° C., and organic components such as added dispersant and binder are removed. If firing is performed with the dispersant and binder remaining, the oxygen concentration in the firing device is likely to fluctuate due to decomposition and oxidation of the organic components, greatly affecting the magnetic properties, making it difficult to produce stably. It is. Further, these organic components cause the control of the porosity, that is, the fluctuation of the crystal growth of ferrite.
その後、得られた造粒物を、酸素濃度の制御された雰囲気下で、８００〜１５００℃の温度で、１〜２４時間保持し、本焼成を行う。その際、ロータリー式電気炉やバッチ式電気炉または連続式電気炉等を使用し、焼成時の雰囲気も、窒素等の不活性ガスや水素や一酸化炭素等の還元性ガスを導入して、酸素濃度の制御を行ってもよい。 Thereafter, the obtained granulated product is held at a temperature of 800 to 1500 ° C. for 1 to 24 hours in an atmosphere in which the oxygen concentration is controlled to perform main firing. At that time, using a rotary electric furnace, a batch electric furnace or a continuous electric furnace, the atmosphere at the time of firing also introduces an inert gas such as nitrogen or a reducing gas such as hydrogen or carbon monoxide, The oxygen concentration may be controlled.
このようにして得られた焼成物を、粉砕し、分級する。分級方法としては、既存の風力分級、メッシュ濾過法、沈降法など用いて所望の粒径に粒度調整する。このようにして、所定の細孔容積及びピーク細孔径を有する多孔質フェライト粒子（フェライトキャリア芯材）を調製する。 The fired product thus obtained is pulverized and classified. As a classification method, the particle size is adjusted to a desired particle size using an existing air classification, mesh filtration method, sedimentation method, or the like. In this way, porous ferrite particles (ferrite carrier core material) having a predetermined pore volume and peak pore diameter are prepared.
多孔質フェライト粒子の細孔容積やピーク細孔径を制御するためには、次のように製造工程を調整することが望ましい。すなわち、多孔質フェライト粒子の細孔容積は、主に本焼成温度で制御でき、温度が高いと細孔容積は小さくなり、温度が低いと細孔容積は大きくなる。また、多孔質フェライト粒子のピーク細孔径は主に仮焼成後の粉砕強度で制御でき、粉砕が弱いとピーク細孔径は大きくなり、粉砕が強いとピーク細孔径は小さくなる。 In order to control the pore volume and the peak pore diameter of the porous ferrite particles, it is desirable to adjust the production process as follows. That is, the pore volume of the porous ferrite particles can be controlled mainly by the main firing temperature. When the temperature is high, the pore volume is small, and when the temperature is low, the pore volume is large. In addition, the peak pore diameter of the porous ferrite particles can be controlled mainly by the pulverization strength after pre-calcination. When the pulverization is weak, the peak pore diameter increases, and when the pulverization is strong, the peak pore diameter decreases.
このようにして得られた多孔質粒子からなるフェライトキャリア芯材の空隙に非磁性成分からなる充填材を充填することによって、キャリア用芯材を得ることができる。充填方法としては、様々な方法が使用でき、例えば、乾式法、流動床によるスプレードライ方式、ロータリードライ方式、万能攪拌機等による液浸乾燥法等が挙げられる。 A carrier core material can be obtained by filling the voids of the ferrite carrier core material made of porous particles thus obtained with a filler made of a nonmagnetic component. Various methods can be used as the filling method, and examples include a dry method, a spray drying method using a fluidized bed, a rotary drying method, an immersion drying method using a universal stirrer, and the like.
充填材を充填する工程において、減圧下で多孔質フェライト粒子と充填材を混合撹拌しながら、多孔質フェライト粒子の空隙に充填材を充填することが好ましい。このように減圧下で充填材を充填することによって、空隙部分に効率良く充填材を充填することができる。減圧の程度としては、１０〜７００ｍｍＨｇが好ましい。７００ｍｍＨｇを超えると減圧する効果がなく、１０ｍｍＨｇ未満では、充填工程中に充填材溶液が沸騰しやすくなるため、効率良い充填が困難となる。 In the step of filling the filler, it is preferable to fill the filler in the voids of the porous ferrite particles while mixing and stirring the porous ferrite particles and the filler under reduced pressure. Thus, by filling the filler under reduced pressure, the gap can be efficiently filled with the filler. The degree of decompression is preferably 10 to 700 mmHg. If it exceeds 700 mmHg, there is no effect of reducing the pressure, and if it is less than 10 mmHg, the filler solution is likely to boil during the filling step, making efficient filling difficult.
充填材を充填させた後、必要に応じて各種の方式によって加熱し、充填した樹脂を芯材に密着させる。加熱方式としては、外部加熱方式又は内部加熱方式のいずれでもよく、例えば固定式又は流動式電気炉、ロータリー式電気炉、バーナー炉でもよく、もしくはマイクロウェーブによる焼き付けでもよい。温度は、充填する充填材によって異なるが、融点又はガラス転移点以上の温度は必要であり、充分硬化が進む温度まで上げることにより、衝撃に対して強いキャリア用芯材を得ることができる。 After filling with the filler, it is heated by various methods as necessary, and the filled resin is brought into close contact with the core material. The heating method may be either an external heating method or an internal heating method, and may be, for example, a fixed or fluid electric furnace, a rotary electric furnace, a burner furnace, or a microwave baking. Although the temperature varies depending on the filler to be filled, a temperature equal to or higher than the melting point or glass transition point is necessary. By raising the temperature to a temperature at which the curing proceeds sufficiently, a carrier core material resistant to impact can be obtained.
ところで、上述したように、充填材の非磁性成分として、シリコーン樹脂等のシロキサン結合を有するものを用いた場合、蛍光Ｘ線元素分析によって測定されたキャリア用芯材のＳｉ／Ｆｅ値を制御することが望ましい。Ｓｉ／Ｆｅ値を制御するためには、下記のように製造工程を調整することが望ましい。 By the way, as described above, when the non-magnetic component of the filler is a material having a siloxane bond such as a silicone resin, the Si / Fe value of the carrier core material measured by fluorescent X-ray elemental analysis is controlled. It is desirable. In order to control the Si / Fe value, it is desirable to adjust the manufacturing process as follows.
この際、最も重要なことは、多孔質フェライト粒子の細孔容積に応じて充填材充填量を増減させることであり、このことによってキャリア用芯材のＳｉ／Ｆｅ値を制御することができる。さらに、また、多孔質フェライト粒子に充填材を充填する際に、減圧下で充填材を充填し、大気に戻してトルエンを除去したあと、更に一定時間の適度な撹拌ストレスを加えて、粒子表面を均一する工程を経てから加熱硬化することである。このことによって、充填材を充填したフェライト粒子表面の充填性が均一となり、Ｓｉ／Ｆｅ値のバラツキが低減されると共に、キャリア特性の制御が可能となる。 At this time, the most important thing is to increase / decrease the filling amount of the filler according to the pore volume of the porous ferrite particles, whereby the Si / Fe value of the carrier core material can be controlled. Furthermore, when filling the porous ferrite particles with a filler, the filler is filled under reduced pressure, returned to the atmosphere to remove toluene, and then subjected to an appropriate stirring stress for a certain period of time to obtain a particle surface. It is to heat-harden after passing through the process of homogenizing. As a result, the filling property of the ferrite particle surface filled with the filler becomes uniform, the variation in the Si / Fe value is reduced, and the carrier characteristics can be controlled.
＜キャリアの製造＞
上述のようにして得たキャリア用芯材の表面に、樹脂からなる被覆層を設けることにより、キャリアを得ることができる。キャリア特性、特に帯電特性を初めとする電気特性は、キャリア表面に存在する材料や性状に影響されることが多い。したがって、適切な樹脂を表面被覆することによって、所望とするキャリア特性を精度良く調整することができる。被覆する方法としては、公知の方法、例えば刷毛塗り法、乾式法、流動床によるスプレードライ方式、ロータリードライ方式、万能攪拌機による液浸乾燥法等により被覆することができる。被覆率を向上させるためには、流動床による方法が好ましい。樹脂被覆後、焼き付けする場合には、外部加熱方式又は内部加熱方式のいずれでもよく、例えば固定式又は流動式電気炉、ロータリー式電気炉、バーナー炉でもよく、もしくはマイクロウェーブによる焼き付けでもよい。焼き付けの温度は使用する樹脂により異なるが、融点又はガラス転移点以上の温度とすることが望ましく、充分硬化が進む温度まで上げることがより望ましい。
<Manufacture of carriers>
A carrier can be obtained by providing a coating layer made of resin on the surface of the carrier core material obtained as described above. Carrier characteristics, particularly electrical characteristics such as charging characteristics, are often influenced by materials and properties existing on the surface of the carrier. Therefore, desired carrier characteristics can be accurately adjusted by coating the surface with an appropriate resin. As a coating method, the coating can be performed by a known method such as a brush coating method, a dry method, a spray drying method using a fluidized bed, a rotary drying method, an immersion drying method using a universal stirrer, or the like. In order to improve the coverage, a fluidized bed method is preferred. In the case of baking after resin coating, either an external heating method or an internal heating method may be used. For example, a stationary or fluid electric furnace, a rotary electric furnace, a burner furnace, or microwave baking may be used. Although the baking temperature varies depending on the resin to be used, it is desirable that the temperature be equal to or higher than the melting point or the glass transition point, and it is more desirable to raise it to a temperature at which sufficient curing proceeds.
本発明を以下の例によってさらに具体的に説明する。 The present invention is more specifically described by the following examples.
例１
（１）フェライトキャリア芯材の作製
ＭｎＯ：３８ｍｏｌ％、ＭｇＯ：１１ｍｏｌ％、Ｆｅ２Ｏ３：５０．３ｍｏｌ％及びＳｒＯ：０．７ｍｏｌ％になるように原料を秤量し、乾式のメディアミル（振動ミル、１／８インチ径のステンレスビーズ）で４．５時間粉砕し、得られた粉砕物をローラーコンパクターにて、約１ｍｍ角のペレットにした。ＭｎＯ原料としては四酸化三マンガンを、ＭｇＯ原料としては水酸化マグネシウムを、ＳｒＯ原料としては、炭酸ストロンチウムを用いた。このペレットを目開き３ｍｍの振動篩にて粗粉を除去し、次いで目開き０．５ｍｍの振動篩にて微粉を除去した後、ロータリー式電気炉で、１０５０℃で３時間加熱し、仮焼成を行った。
Example 1
(1) Preparation of MnO ferrite carrier core material: 38mol%, MgO: 11mol% , Fe 2 O 3: 50.3mol% and SrO: raw materials were weighed so that 0.7 mol%, dry media mill (vibration Mill, 1/8 inch diameter stainless steel beads) for 4.5 hours, and the resulting pulverized product was formed into approximately 1 mm square pellets using a roller compactor. Trimanganese tetraoxide was used as the MnO raw material, magnesium hydroxide was used as the MgO raw material, and strontium carbonate was used as the SrO raw material. After removing the coarse powder with a vibrating sieve having a mesh opening of 3 mm and then removing the fine powder with a vibrating sieve having a mesh opening of 0.5 mm, the pellets are heated in a rotary electric furnace at 1050 ° C. for 3 hours and pre-baked. Went.
次いで、乾式のメディアミル（振動ミル、１／８インチ径のステンレスビーズ）を用いて平均粒径が約４μｍまで粉砕した後、水を加え、さらに湿式のメディアミル（縦型ビーズミル、１／１６インチ径のステンレスビーズ）を用いて１０時間粉砕した。このスラリーの粒径（粉砕後の一次粒子径）をマイクロトラックにて測定した結果、Ｄ５０は１．４μｍであった。このスラリーに分散剤を適量添加し、バインダーとしてＰＶＡ（２０％溶液）を固形分に対して０．２重量％添加し、次いでスプレードライヤーにより造粒、乾燥し、得られた粒子（造粒物）の粒度調整を行い、その後、ロータリー式電気炉で、７００℃で２時間加熱し、分散剤やバインダーといった有機成分の除去を行った。 Next, after pulverizing to an average particle size of about 4 μm using a dry media mill (vibration mill, 1/8 inch diameter stainless steel beads), water was added, and a wet media mill (vertical bead mill, 1/16) was added. Inch stainless steel beads) for 10 hours. The slurry particle size (primary particle size after grinding) results measured at Microtrac, D 50 was 1.4 [mu] m. An appropriate amount of a dispersant is added to this slurry, 0.2% by weight of PVA (20% solution) as a binder is added based on the solid content, and then granulated and dried by a spray dryer. ), And then heated at 700 ° C. for 2 hours in a rotary electric furnace to remove organic components such as a dispersant and a binder.
その後、トンネル式電気炉にて、焼成温度１０８５℃、酸素ガス濃度０容量％雰囲気下にて、５時間保持した。この時、昇温速度を１５０℃／時、降温速度を１１０℃／時とした。その後、解砕し、さらに分級して粒度調整を行い、磁力選鉱により低磁力品を分別し、多孔質フェライト粒子からなるフェライトキャリア芯材を得た。 Thereafter, it was kept in a tunnel type electric furnace for 5 hours in a firing temperature of 1085 ° C. and an oxygen gas concentration of 0 vol%. At this time, the temperature rising rate was 150 ° C./hour and the temperature decreasing rate was 110 ° C./hour. Thereafter, the mixture was crushed, further classified to adjust the particle size, and the low-magnetic force product was separated by magnetic separation, so that a ferrite carrier core material composed of porous ferrite particles was obtained.
（２）キャリア用芯材の作製
メチルシリコーン樹脂溶液を３０重量部（樹脂溶液濃度２０％のため固形分としては６重量部）に、触媒として、チタンジイソプロポキシビス（エチルアセトアセテート）を、樹脂固形分に対して２５重量％（Ｔｉ原子換算で３重量％）加えたあと、アミノシランカップリング剤として３−アミノプロピルトリエトキシシシランを、樹脂固形分に対して５重量％添加し、さらに導電性制御剤としてカーボンブラック（Ｃａｂｏｔ社製、Ｍｏｇｕｌ Ｌ）を樹脂固形分に対して１０．０重量％添加して充填樹脂溶液を得た。
(2) Preparation of carrier core material 30 parts by weight of methylsilicone resin solution (6 parts by weight as the solid content due to a resin solution concentration of 20%), and titanium diisopropoxybis (ethyl acetoacetate) as a catalyst, After adding 25% by weight (3% by weight in terms of Ti atom) with respect to the resin solid content, 5% by weight of 3-aminopropyltriethoxysilane is added as an aminosilane coupling agent with respect to the resin solid content. Carbon black (manufactured by Cabot, Mogul L) as a conductivity control agent was added in an amount of 10.0% by weight based on the solid content of the resin to obtain a filled resin solution.
この樹脂溶液を、上記多孔質フェライト粒子１００重量部と、６０℃、６．７ｋＰａ（約５０ｍｍＨｇ）の減圧下で混合撹拌し、トルエンを揮発させながら、樹脂を多孔質フェライト粒子の空隙に浸透、充填させた。容器内を常圧に戻し、常圧下で撹拌を続けながら、トルエンをほぼ完全に除去したのち、充填装置内から取り出し、容器に入れ、熱風加熱式のオーブンに入れ、２２０℃で１．５時間、加熱処理を行った。 This resin solution was mixed and stirred with 100 parts by weight of the porous ferrite particles at 60 ° C. under a reduced pressure of 6.7 kPa (about 50 mmHg), and the resin was permeated into the voids of the porous ferrite particles while volatilizing toluene. Filled. The inside of the container is returned to normal pressure, and toluene is almost completely removed while continuing stirring under normal pressure. Then, the toluene is taken out from the filling apparatus, placed in the container, placed in a hot air heating oven, and heated at 220 ° C. for 1.5 hours. The heat treatment was performed.
その後、室温まで冷却し、樹脂が硬化されたフェライト粒子を取り出し、２００Ｍの目開きの振動篩にて粒子の凝集を解し、磁力選鉱機を用いて、非磁性物を取り除いた。その後、再度振動篩にて粗大粒子を取り除き樹脂が充填されたフェライト粒子を得た。 Then, it cooled to room temperature, the ferrite particle | grains by which resin was hardened were taken out, the aggregation of particle | grains was released with the vibration sieve of 200M opening, and the nonmagnetic substance was removed using the magnetic separator. Thereafter, coarse particles were removed again with a vibrating sieve to obtain ferrite particles filled with resin.
（３）キャリアの作製
固形のアクリル樹脂（三菱レイヨン社製、ＢＲ−７３）を準備し、上記アクリル樹脂２０重量部をトルエン８０重量部に混合して、アクリル樹脂をトルエンに溶解させ、樹脂溶液を調製した。この樹脂溶液に、更に導電性制御剤としてカーボンブラック（Ｃａｂｏｔ社製、Ｍｏｇｕｌ Ｌ）をアクリル樹脂に対して５重量％添加し、被覆樹脂溶液を得た。
(3) Preparation of carrier A solid acrylic resin (manufactured by Mitsubishi Rayon Co., Ltd., BR-73) is prepared, 20 parts by weight of the acrylic resin is mixed with 80 parts by weight of toluene, the acrylic resin is dissolved in toluene, and a resin solution Was prepared. To this resin solution, 5% by weight of carbon black (manufactured by Cabot, Mogul L) as a conductivity control agent was added to the acrylic resin to obtain a coating resin solution.
得られた樹脂が充填されたフェライト粒子を万能混合撹拌器に投入し、上記のアクリル樹脂溶液を添加して、液浸乾燥法により樹脂被覆を行った。この際、アクリル樹脂は、樹脂充填後のフェライト粒子の重量に対して２重量％とした。被覆した後、１４５℃で２時間加熱を行ったのち、２００Ｍの目開きの振動篩にて粒子の凝集を解し、磁力選鉱機を用いて、非磁性物を取り除いた。その後、再度振動篩にて粗大粒子を取り除き表面に被覆樹脂を施した樹脂充填型フェライトキャリアを得た。 The ferrite particles filled with the obtained resin were put into a universal mixing stirrer, the above acrylic resin solution was added, and the resin coating was performed by the immersion drying method. At this time, the acrylic resin was 2% by weight with respect to the weight of the ferrite particles after filling the resin. After the coating, the mixture was heated at 145 ° C. for 2 hours, and then the particles were agglomerated with a vibrating sieve having a 200-M aperture, and the non-magnetic material was removed using a magnetic separator. Thereafter, coarse particles were again removed with a vibrating sieve to obtain a resin-filled ferrite carrier having a coating resin on the surface.
（４）評価
得られたフェライトキャリア芯材、キャリア用芯材及びキャリアについて、各種特性の評価を以下のとおり行った。
(4) Evaluation Various characteristics of the obtained ferrite carrier core material, carrier core material and carrier were evaluated as follows.
＜細孔容積及び細孔径＞
細孔容積及び細孔径の測定は次のようにして行った。すなわち、水銀ポロシメーター（Ｔｈｅｒｍｏ Ｆｉｓｈｅｒ Ｓｃｉｅｎｔｉｆｉｃ社製、Ｐａｓｃａｌ１４０及びＰａｓｃａｌ２４０）を用いて測定した。ディラトメーターはＣＤ３Ｐ（粉体用）を使用し、サンプルは複数の穴を開けた市販のゼラチン製カプセルに入れて、ディラトメーター内に入れた。Ｐａｓｃａｌ１４０で脱気後、水銀を充填し低圧領域（０〜４００Ｋｐａ）で測定し、１ｓｔ Ｒｕｎとした。次に再び脱気と低圧領域（０〜４００Ｋｐａ）での測定を行い、２ｎｄ Ｒｕｎとした。２ｎｄ Ｒｕｎの後、ディラトメーターと水銀とカプセルとサンプルを合わせた重量を測定した。次にＰａｓｃａｌ２４０で高圧領域（０．１Ｍｐａ〜２００Ｍｐａ）で測定した。この高圧部の測定で得られた水銀圧入量をもって、多孔質フェライト粒子の細孔容積及びピーク細孔径を求めた。また、細孔径を求める際には水銀の表面張力を４８０ｄｙｎ／ｃｍ、接触角を１４１．３°として計算した。
<Pore volume and pore diameter>
The pore volume and pore diameter were measured as follows. That is, it measured using the mercury porosimeter (Thermo Fisher Scientific company Pascal140 and Pascal240). As the dilatometer, CD3P (for powder) was used, and the sample was placed in a commercially available gelatin capsule having a plurality of holes and placed in the dilatometer. After degassing with Pascal 140, it was filled with mercury and measured in the low pressure region (0 to 400 Kpa) to obtain 1st Run. Next, deaeration and measurement in a low pressure region (0 to 400 Kpa) were performed again to obtain 2nd Run. After 2nd Run, the combined weight of the dilatometer, mercury, capsule and sample was measured. Next, it measured in Pascal240 in the high voltage | pressure range (0.1 Mpa-200 Mpa). The pore volume and peak pore diameter of the porous ferrite particles were determined from the amount of mercury intrusion obtained by the measurement at the high pressure part. Further, when determining the pore diameter, the surface tension of mercury was 480 dyn / cm and the contact angle was 141.3 °.
＜飽和磁化＞
飽和磁化の測定は、積分型Ｂ−Ｈトレーサー（株式会社理研電子製、ＢＨＵ−６０型）を使用して測定した。電磁石間に磁場測定用Ｈコイル及び磁化測定用４πＩコイルを入れ、試料を４πＩコイルに入れた。電磁石の電流を変化させ磁場Ｈを変化させたＨコイル及び４πＩコイルの出力をそれぞれ積分し、Ｈ出力をＸ軸に、４πＩコイルの出力をＹ軸に、ヒステリシスループを記録紙に描き、飽和磁化を求めた。ここで測定条件としては、試料充填量：約１ｇ、試料充填セル：内径７ｍｍ±０．０２ｍｍ、高さ１０ｍｍ±０．１ｍｍ、４πＩコイル：巻数３０回にて測定した。
<Saturation magnetization>
The saturation magnetization was measured using an integral type BH tracer (manufactured by Riken Electronics Co., Ltd., BHU-60 type). An H coil for magnetic field measurement and a 4πI coil for magnetization measurement were placed between the electromagnets, and a sample was placed in the 4πI coil. Integrate the outputs of the H coil and 4πI coil that changed the current of the electromagnet and changed the magnetic field H, draw the hysteresis output on the X axis, the output of the 4πI coil on the Y axis, and the hysteresis loop on the recording paper. Asked. As measurement conditions, sample filling amount: about 1 g, sample filling cell: inner diameter 7 mm ± 0.02 mm, height 10 mm ± 0.1 mm, 4πI coil: measured with 30 turns.
＜電気抵抗＞
電気抵抗の測定は次のようにして行った。すなわち、磁極間間隔６．５ｍｍにてＮ極及びＳ極を対向させ、非磁性の平行平板電極（面積１０×４０ｍｍ）に、試料２００ｍｇを秤量して挿入した。磁極（表面磁束密度：１５００Ｇａｕｓｓ、対向電極面積：１０×３０ｍｍ）を平行平板電極に付けることにより電極間に試料を保持させ、印加電圧２５０Ｖでの抵抗を絶縁抵抗計にて測定し、電気抵抗とした。
<Electrical resistance>
The electrical resistance was measured as follows. That is, the N pole and the S pole were made to face each other with a gap between the magnetic poles of 6.5 mm, and 200 mg of the sample was weighed and inserted into a nonmagnetic parallel plate electrode (area 10 × 40 mm). A sample is held between the electrodes by attaching magnetic poles (surface magnetic flux density: 1500 Gauss, counter electrode area: 10 × 30 mm) to the parallel plate electrodes, and the resistance at an applied voltage of 250 V is measured with an insulation resistance meter. did.
＜Ｓｉ／Ｆｅ値＞
Ｓｉ／Ｆｅ値の測定を次のようにして行った。すなわち、蛍光Ｘ線元素分析装置（株式会社リガク製、ＺＳＸ１００ｓ）を用い、サンプル約５ｇを真空用粉末試料容器（株式会社リガク製、ＲＳ６４０）に入れ、試料フォルダにセットし、前記分析装置にて、ＳｉとＦｅの測定を行った。ここで、測定条件としては、ＳｉについてはＳｉ−Ｋα線を測定線とし、管電圧５０ｋＶ、管電流５０ｍＡ、分光結晶にＰＥＴ、検出器としてＰＣ（プロポーショナルカウンター）を用いた。ＦｅについてはＦｅ−Ｋα線を測定線とし、管電圧５０ｋＶ、管電流５０ｍＡ、分光結晶にＬｉＦ、検出器としてＳＣ（シンチレーションカウンター）を用いた。得られたそれぞれの蛍光Ｘ線強度を用い、強度比（Ｓｉ強度／Ｆｅ強度）を計算し、Ｓｉ／Ｆｅ値とした。
<Si / Fe value>
The Si / Fe value was measured as follows. That is, using a fluorescent X-ray elemental analyzer (ZSX100s, manufactured by Rigaku Corporation), about 5 g of a sample is placed in a vacuum powder sample container (RS640, manufactured by Rigaku Corporation) and set in a sample folder. , Si and Fe were measured. Here, as measurement conditions, for Si, a Si—Kα line was used as a measurement line, a tube voltage of 50 kV, a tube current of 50 mA, PET as a spectroscopic crystal, and a PC (proportional counter) as a detector. For Fe, the Fe—Kα line was used as the measurement line, the tube voltage was 50 kV, the tube current was 50 mA, LiF was used as the spectroscopic crystal, and SC (scintillation counter) was used as the detector. Using the obtained fluorescent X-ray intensities, the intensity ratio (Si intensity / Fe intensity) was calculated and used as the Si / Fe value.
＜真比重＞
真比重は、ＪＩＳ Ｒ９３０１−２−１に準拠して、ピークメーターを用いて測定した。ここで溶媒としてメタノールを用い、温度２５℃で測定を行った。
<True specific gravity>
The true specific gravity was measured using a peak meter in accordance with JIS R9301-2-1. Here, methanol was used as a solvent, and measurement was performed at a temperature of 25 ° C.
＜透過度＞
透過度の測定は次のようにして行った。すなわち、キャリア１５ｇと水２５ｇを５０ｃｃのガラス瓶に入れ、そのガラス瓶をボールミルにて１５０ｒｐｍで２０分攪拌した後、静置してから上澄み液を回収した。回収した上澄み液の吸収スペクトルを分光光度計（島津製作所製、ＵＶ−１８００）にて測定し、５００ｎｍにおける透過率を測定し、その測定値を透過度とした。
<Transparency>
The transmittance was measured as follows. That is, 15 g of carrier and 25 g of water were put into a 50 cc glass bottle, the glass bottle was stirred at 150 rpm for 20 minutes with a ball mill, and allowed to stand, and then the supernatant was collected. The absorption spectrum of the collected supernatant was measured with a spectrophotometer (manufactured by Shimadzu Corporation, UV-1800), the transmittance at 500 nm was measured, and the measured value was taken as the transmittance.
＜キャリア電流＞
キャリア電流の測定は次のようにして行った。すなわち、試料８００ｇを秤量し、温度２０〜２６℃、湿度５０〜６０％ＲＨの環境に１５分以上曝露した後、マグネットローラーとＡｌ素管を電極とし、その間隔を４．５ｍｍに配置した電流測定装置を用いて印可電圧５００Ｖにて測定し、キャリア電流を求めた。
<Carrier current>
The carrier current was measured as follows. That is, 800 g of a sample was weighed and exposed to an environment with a temperature of 20 to 26 ° C. and a humidity of 50 to 60% RH for 15 minutes or more, and then a current with a magnet roller and an Al base tube as an electrode and an interval of 4.5 mm. The carrier current was obtained by measuring at an applied voltage of 500 V using a measuring device.
＜飛散量＞
飛散量の測定は次のようにして行った。すなわち、直径５０ｍｍ、表面磁力１０００Ｇａｕｓｓの磁気ドラムにキャリアを５００ｇ充填し、２７０ｒｐｍで３０分間回転させた後、飛散した粒子を回収し、その重量を測定して飛散量とした。
<Amount of splash>
The amount of scattering was measured as follows. That is, a magnetic drum having a diameter of 50 mm and a surface magnetic force of 1000 Gauss was charged with 500 g of carrier and rotated at 270 rpm for 30 minutes, and then the scattered particles were collected and the weight was measured to determine the amount of scattering.
例２及び４〜１５
（１）フェライトキャリア芯材の作製
トンネル式電気炉での本焼成工程における焼成温度と酸素ガス濃度を、表１に示されるとおりとした以外は、例１と同様にしてフェライトキャリア芯材（多孔質フェライト粒子）を作製した。
Examples 2 and 4-15
(1) Preparation of ferrite carrier core material A ferrite carrier core material (porous) was prepared in the same manner as in Example 1 except that the firing temperature and oxygen gas concentration in the main firing step in the tunnel type electric furnace were as shown in Table 1. Ferrite particles).
（２）キャリア用芯材の作製
充填樹脂溶液作製工程におけるメチルシリコーン樹脂量（固形分量）と導電性制御剤（カーボンブラック）の添加量を、表１に示されるとおりとした以外は、例１と同様にしてキャリア用芯材の作製を行った。
(2) Preparation of carrier core material Example 1 except that the amount of methyl silicone resin (solid content) and the amount of conductivity control agent (carbon black) added in the filling resin solution preparation step were as shown in Table 1. The core material for carriers was produced in the same manner as described above.
（３）キャリアの作製
被覆樹脂溶液作製工程における導電性制御剤（カーボンブラック）の添加量と、樹脂被覆工程におけるアクリル樹脂量を、表１に示されるとおりとした以外は、例１と同様にしてキャリアの作製を行った。
(3) Preparation of carrier As in Example 1, except that the addition amount of the conductivity control agent (carbon black) in the coating resin solution preparation step and the acrylic resin amount in the resin coating step were as shown in Table 1. The carrier was manufactured.
例３
（１）フェライトキャリア芯材の作製
トンネル式電気炉での本焼成工程における焼成温度と酸素ガス濃度を、表１に示されるとおりとした以外は、例１と同様にしてフェライトキャリア芯材（多孔質フェライト粒子）を作製した。
Example 3
(1) Preparation of ferrite carrier core material A ferrite carrier core material (porous) was prepared in the same manner as in Example 1 except that the firing temperature and oxygen gas concentration in the main firing step in the tunnel type electric furnace were as shown in Table 1. Ferrite particles).
（２）キャリア用芯材の作製
多孔質フェライト粒子１００重量部に、シランカップリング剤（３−グリシドキシプロピルトリメトキシシラン）１２重量部と、シランカップリング剤に対してカーボンブラックを１０重量％と配合し、これらを万能混合機にて液浸乾燥法により十分乾燥するまで樹脂充填を行った。その後、装置内から取り出し、熱風加熱式のオーブンに入れ、２５０℃で１．５時間加熱処理を行った。
(2) Production of carrier core material 100 parts by weight of porous ferrite particles, 12 parts by weight of silane coupling agent (3-glycidoxypropyltrimethoxysilane), and 10 parts by weight of carbon black relative to the silane coupling agent These were mixed with resin until they were sufficiently dried by the immersion drying method in a universal mixer. Then, it took out from the inside of an apparatus, put into the oven of the hot air heating type, and heat-processed at 250 degreeC for 1.5 hours.
（３）キャリアの作製
被覆樹脂溶液作製工程における導電性制御剤（カーボンブラック）の添加量と、樹脂被覆工程におけるアクリル樹脂量を、表１に示されるとおりとした以外は、例１と同様にしてキャリアの作製を行った。
(3) Preparation of carrier As in Example 1, except that the addition amount of the conductivity control agent (carbon black) in the coating resin solution preparation step and the acrylic resin amount in the resin coating step were as shown in Table 1. The carrier was manufactured.
結果
例１〜１５において得られた評価結果は表２に示されるとおりであった。実施例である例１〜６においては、飛散量が小さく、キャリア電流値が適切な範囲内にあるとともに、透過度が十分に高いものであった。一方、比較例である例７〜１２及び１４〜１５においては、透過度、飛散量、及びキャリア電流値のいずれかに問題があった。なお、例１３においては十分な樹脂充填が行えず、キャリア用芯材が得られなかった。これらの結果から、本発明によれば、軽量で耐久性に優れるとともに、キャリア飛散が少なく、良好な画像が実現される、キャリア用芯材や該キャリア用芯材を備えたキャリアを提供できることが分かる。
The evaluation results obtained in result examples 1 to 15 were as shown in Table 2. In Examples 1 to 6, which are examples, the scattering amount was small, the carrier current value was within an appropriate range, and the transmittance was sufficiently high. On the other hand, in Examples 7 to 12 and 14 to 15 which are comparative examples, there was a problem in any of the transmittance, the scattering amount, and the carrier current value. In Example 13, sufficient resin filling could not be performed, and a carrier core material could not be obtained. From these results, according to the present invention, it is possible to provide a carrier core material and a carrier provided with the carrier core material, which are lightweight and excellent in durability, have less carrier scattering, and realize a good image. I understand.
Claims (14)
該キャリア用芯材の飽和磁化が６３〜９０Ａ・ｍ２／ｋｇであり、かつ、前記フェライトキャリア芯材の電気抵抗Ａ及びキャリア用芯材の電気抵抗Ｂが、下記式：
−１．０≦Ｌｏｇ１０（Ｂ／Ａ）≦０．７
を満足する、キャリア用芯材。 A carrier core material comprising a ferrite carrier core material composed of porous ferrite particles and a filler composed of a non-magnetic component filled in the voids of the ferrite carrier core material,
The saturation magnetization of the carrier core material is 63 to 90 A · m 2 / kg, and the electrical resistance A of the ferrite carrier core material and the electrical resistance B of the carrier core material are expressed by the following formula:
−1.0 ≦ Log 10 (B / A) ≦ 0.7
Satisfying the core material for carriers.
−０．３≦Ｌｏｇ１０（Ｂ／Ａ）≦０．７
を満足する、請求項１に記載のキャリア用芯材。 The electrical resistance A and electrical resistance B are represented by the following formula:
−0.3 ≦ Log 10 (B / A) ≦ 0.7
The core material for carriers according to claim 1, wherein
７．０≦Ｌｏｇ１０Ｂ≦９．０
を満足する、請求項１〜３のいずれか一項に記載のキャリア用芯材。 The electrical resistance B is represented by the following formula:
7.0 ≦ Log 10 B ≦ 9.0
The core material for carriers according to any one of claims 1 to 3, which satisfies
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2016052127A JP6742119B2 (en) | 2016-03-16 | 2016-03-16 | Core material for carrier, carrier, developer and electrophotographic development system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2016052127A JP6742119B2 (en) | 2016-03-16 | 2016-03-16 | Core material for carrier, carrier, developer and electrophotographic development system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2017167311A true JP2017167311A (en) | 2017-09-21 |
| JP6742119B2 JP6742119B2 (en) | 2020-08-19 |
Family
ID=59913221
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2016052127A Active JP6742119B2 (en) | 2016-03-16 | 2016-03-16 | Core material for carrier, carrier, developer and electrophotographic development system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP6742119B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3686677A1 (en) * | 2019-01-25 | 2020-07-29 | Powdertech Co., Ltd. | Carrier core material for electrophotographic developer and method for producing the same, and carrier for electrophotographic developer and developer containing said carrier core material |
| JP2021124631A (en) * | 2020-02-06 | 2021-08-30 | キヤノン株式会社 | Magnetic carrier and two-component developer |
Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002278165A (en) * | 2001-03-19 | 2002-09-27 | Ricoh Co Ltd | Carrier for electrophotographic developer |
| JP2003295523A (en) * | 2002-04-01 | 2003-10-15 | Canon Inc | Magnetic material distribution type resin carrier and two-component developer |
| JP2009205149A (en) * | 2008-02-01 | 2009-09-10 | Canon Inc | Two-component developer, replenishing developer, and image-forming method using the developer |
| JP2010224054A (en) * | 2009-03-19 | 2010-10-07 | Powdertech Co Ltd | Ferrite carrier for electrophotographic developer and electrophotographic developer using the ferrite carrier |
| JP2011112960A (en) * | 2009-11-27 | 2011-06-09 | Powdertech Co Ltd | Porous ferrite core material for electrophotographic developer, resin-filled ferrite carrier, and electrophotographic developer using the ferrite carrier |
| JP2011145497A (en) * | 2010-01-15 | 2011-07-28 | Canon Inc | Magnetic carrier and two-component developer |
| JP2011164225A (en) * | 2010-02-05 | 2011-08-25 | Powdertech Co Ltd | Ferrite carrier core material of resin filled type for electrophotographic developer, ferrite carrier, and electrophotographic developer using the ferrite carrier |
| JP2013178506A (en) * | 2012-01-31 | 2013-09-09 | Canon Inc | Magnetic carrier, binary system developer and developer for replenishment |
| JP2014197040A (en) * | 2013-03-21 | 2014-10-16 | パウダーテック株式会社 | Resin-filled ferrite carrier core material and ferrite carrier for electrophotographic developer, and electrophotographic developer using the ferrite carrier |
| JP2015007772A (en) * | 2013-05-30 | 2015-01-15 | キヤノン株式会社 | Magnetic carrier, two-component developer, developer for replenishment, and image forming method |
| JP2015138052A (en) * | 2014-01-20 | 2015-07-30 | パウダーテック株式会社 | Ferrite carrier core material and ferrite carrier for electrophotographic developer using ferrite particle having outer shell structure, and electrophotographic developer using the ferrite carrier |
| JP2015197490A (en) * | 2014-03-31 | 2015-11-09 | パウダーテック株式会社 | Resin filled ferrite carrier for electrophotographic developer and electrophotographic developer using the same |
-
2016
- 2016-03-16 JP JP2016052127A patent/JP6742119B2/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002278165A (en) * | 2001-03-19 | 2002-09-27 | Ricoh Co Ltd | Carrier for electrophotographic developer |
| JP2003295523A (en) * | 2002-04-01 | 2003-10-15 | Canon Inc | Magnetic material distribution type resin carrier and two-component developer |
| JP2009205149A (en) * | 2008-02-01 | 2009-09-10 | Canon Inc | Two-component developer, replenishing developer, and image-forming method using the developer |
| JP2010224054A (en) * | 2009-03-19 | 2010-10-07 | Powdertech Co Ltd | Ferrite carrier for electrophotographic developer and electrophotographic developer using the ferrite carrier |
| JP2011112960A (en) * | 2009-11-27 | 2011-06-09 | Powdertech Co Ltd | Porous ferrite core material for electrophotographic developer, resin-filled ferrite carrier, and electrophotographic developer using the ferrite carrier |
| JP2011145497A (en) * | 2010-01-15 | 2011-07-28 | Canon Inc | Magnetic carrier and two-component developer |
| JP2011164225A (en) * | 2010-02-05 | 2011-08-25 | Powdertech Co Ltd | Ferrite carrier core material of resin filled type for electrophotographic developer, ferrite carrier, and electrophotographic developer using the ferrite carrier |
| JP2013178506A (en) * | 2012-01-31 | 2013-09-09 | Canon Inc | Magnetic carrier, binary system developer and developer for replenishment |
| JP2014197040A (en) * | 2013-03-21 | 2014-10-16 | パウダーテック株式会社 | Resin-filled ferrite carrier core material and ferrite carrier for electrophotographic developer, and electrophotographic developer using the ferrite carrier |
| JP2015007772A (en) * | 2013-05-30 | 2015-01-15 | キヤノン株式会社 | Magnetic carrier, two-component developer, developer for replenishment, and image forming method |
| JP2015138052A (en) * | 2014-01-20 | 2015-07-30 | パウダーテック株式会社 | Ferrite carrier core material and ferrite carrier for electrophotographic developer using ferrite particle having outer shell structure, and electrophotographic developer using the ferrite carrier |
| JP2015197490A (en) * | 2014-03-31 | 2015-11-09 | パウダーテック株式会社 | Resin filled ferrite carrier for electrophotographic developer and electrophotographic developer using the same |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3686677A1 (en) * | 2019-01-25 | 2020-07-29 | Powdertech Co., Ltd. | Carrier core material for electrophotographic developer and method for producing the same, and carrier for electrophotographic developer and developer containing said carrier core material |
| US11112716B2 (en) | 2019-01-25 | 2021-09-07 | Powdertech Co., Ltd. | Carrier core material for electrophotographic developer and method for producing the same, and carrier for electrophotographic developer and developer containing said carrier core material |
| JP2021124631A (en) * | 2020-02-06 | 2021-08-30 | キヤノン株式会社 | Magnetic carrier and two-component developer |
| JP7523918B2 (en) | 2020-02-06 | 2024-07-29 | キヤノン株式会社 | Magnetic carrier and two-component developer |
Also Published As
| Publication number | Publication date |
|---|---|
| JP6742119B2 (en) | 2020-08-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8535867B2 (en) | Ferrite core material and ferrite carrier for electrophotographic developer, and electrophotographic developer using the ferrite carrier | |
| EP3032335A1 (en) | Ferrite particles having outer shell structure, ferrite carrier core for electrophotographic developer, and electrophotographic developer | |
| US10564561B2 (en) | Ferrite carrier core material for electrophotographic developer, ferrite carrier for electrophotographic developer, electrophotographic developer, and method for manufacturing ferrite carrier core material for electrophotographic developer | |
| JP2008241742A (en) | Carrier core material for electrophotographic developer and manufacturing method thereof, carrier for electrophotographic developer, and electrophotographic developer | |
| JP5032147B2 (en) | Resin-filled ferrite carrier for electrophotographic developer and electrophotographic developer using the ferrite carrier | |
| JP4963618B2 (en) | Carrier core material for electrophotographic developer, method for producing the same, and electrophotographic developer | |
| JP6742119B2 (en) | Core material for carrier, carrier, developer and electrophotographic development system | |
| JP7526527B2 (en) | Ferrite particles, carrier for electrophotographic developer, electrophotographic developer, and method for producing ferrite particles | |
| JP2021088487A (en) | Ferrite mixed powder, carrier core material for electrophotographic developer, carrier for electrophotographic developer and electrophotographic developer | |
| US10754271B2 (en) | Magnetic core material for electrophotographic developer, carrier for electrophotographic developer, and developer | |
| JP6319779B1 (en) | Magnetic core material for electrophotographic developer, carrier for electrophotographic developer and developer | |
| US10969706B2 (en) | Magnetic core material for electrophotographic developer, carrier for electrophotographic developer, and developer | |
| US10775711B2 (en) | Ferrite carrier core material for electrophotographic developer, ferrite carrier for electrophotographic developer, electrophotographic developer, and method for manufacturing ferrite carrier core material for electrophotographic developer | |
| US10996579B2 (en) | Magnetic core material for electrophotographic developer, carrier for electrophotographic developer, and developer | |
| JP6302123B1 (en) | Magnetic core material for electrophotographic developer, carrier for electrophotographic developer and developer | |
| CN109839808B (en) | Ferrite carrier core material for electrophotographic developer, carrier, and developer | |
| JP2021193062A (en) | Ferrite particle, carrier for electrophotographic developing agent and electrophotographic developing agent, and method of manufacturing ferrite particle | |
| JP2016139008A (en) | Carrier and electrophotographic developer prepared with carrier | |
| JP2019040174A (en) | Magnetic core material for electrographic developer, carrier for electrographic developer and developer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A625 | Written request for application examination (by other person) |
Free format text: JAPANESE INTERMEDIATE CODE: A625 Effective date: 20181226 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20191009 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20191031 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20191226 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20200312 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20200508 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20200708 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20200728 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 6742119 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |