JP2005243811A - Magnetorheological fluid - Google Patents

Magnetorheological fluid Download PDF

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JP2005243811A
JP2005243811A JP2004049971A JP2004049971A JP2005243811A JP 2005243811 A JP2005243811 A JP 2005243811A JP 2004049971 A JP2004049971 A JP 2004049971A JP 2004049971 A JP2004049971 A JP 2004049971A JP 2005243811 A JP2005243811 A JP 2005243811A
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mrf
dispersion medium
magnetorheological fluid
dispersed
rapeseed oil
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Ryoichi Hanaoka
良一 花岡
Shinzo Takada
新三 高田
Tadashi Fukami
正 深見
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Kanazawa Institute of Technology (KIT)
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Kanazawa Institute of Technology (KIT)
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Abstract

<P>PROBLEM TO BE SOLVED: To form a magnetorheological fluid which can replace a conventional rheology fluid from the viewpoint of an environmental problem, is gentle to an environment (a load exerted on the environment is small), and is excellent in the dispersion stability of dispersed particles. <P>SOLUTION: A dispersant is obtained by mixedly adding Lucentite (R) which is a swollen-layer-like clay mineral or an anti-sag agent for a nonaqueous paint to a rape oil which is unsaturated fatty acid. A spherical carbonyl iron powder is dispersed in the dispersant to form the magnetorheological fluid. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

この発明は、外部から加わる磁界の有無によって粘度が大幅に変化し流動特性が極めて大きく変化する磁気レオロジー流体（Magnetorheological Fluid）（「ＭＲＦ」と略す）に関するものである。 The present invention relates to a magnetorheological fluid (abbreviated as “MRF”) in which the viscosity changes greatly depending on the presence or absence of a magnetic field applied from the outside, and the flow characteristics change extremely greatly.

ＭＲＦ（磁気レオロジー流体）は、分散媒（キャリアー流体）と分散粒子から成る流体で、外部磁界Ｈが印加されていないとき（外部磁界の強さＨ＝０のとき）にはニュートン流体（Newton 流体）の特性を示し、外部磁界が印加されるとその流体の見掛けの粘度が著しく上昇し降伏応力が現れビンガム流体（Bingham 流体）の特性を示す。そしてまた磁界を取り除くとＭＲＦの粘度は再び元の粘度に戻る可逆性を示す。ＭＲＦのそのような粘性特性はＭＲ効果と呼ばれ、その粘度変化は初期状態に対して１０５〜１０６倍にもなる。 MRF (magnetorheological fluid) is a fluid composed of a dispersion medium (carrier fluid) and dispersed particles. When an external magnetic field H is not applied (when the external magnetic field strength H = 0), a Newtonian fluid (Newtonian fluid). ), When an external magnetic field is applied, the apparent viscosity of the fluid rises significantly, yield stress appears, and the characteristics of Bingham fluid (Bingham fluid). When the magnetic field is removed, the viscosity of the MRF shows reversibility that returns to the original viscosity again. Such a viscosity characteristic of MRF is called MR effect, and its viscosity change is 10 5 to 10 6 times that of the initial state.

従来からＭＲＦの分散媒としてシリコーン油が用いられていたが、シリコーン油を分散媒とし金属磁性粉を分散粒子として用いるＭＲＦでは、分散媒と分散粒子との間に大きな密度差があるために、そのＭＲＦを静置しておくと短時間のうちに分散粒子が沈降して分散媒中における分散粒子の安定性が損なわれＭＲＦの機能を奏しなくなることから、この分散粒子の沈降を抑制してＭＲＦにおける分散粒子の分散の均等性・安定性を高める手段が本願発明者によって既に開発され特願２００２−２３１４４６号特許出願として提示されている。すなわち特願２００２−２３１４４６号明細書・図面（特許文献１）に示されるように、分散媒にチキソトロピー（thixotropy）性（外部から力や衝撃を与えるまでは高粘度状態を保ち、力や衝撃が加わると瞬時に液状となる性質）を付与した分散粒子無沈降型ＭＲＦが従来提案されている。そしてそこに用いられるチキソトロピー性ＭＲＦの分散媒として、膨潤性層状粘土鉱物のモンモリナイトを主成分とするスメクタイト系ベントナイトであるところのルーセンタイトにフタル酸ジオクチルなどの油系液体（「ＤＯＰ」と略す）を取り込ませた流体が例示され、分散粒子として粒径数μmの球状カルボニル鉄粉を使用することが例示されている。しかし、従来分散媒として用いたシリコーン油では分散粒子の分散安定性に問題があり、またルーセンタイトにＤＯＰを取り込ませた分散媒では、ＤＯＰの環境負荷が大きいことから、ＭＲＦの実用化段階での将来性が懸念される問題があった。
特願２００２−２３１４４６号明細書・図面 Conventionally, silicone oil has been used as a dispersion medium for MRF, but in MRF using silicone oil as a dispersion medium and metal magnetic powder as dispersion particles, there is a large density difference between the dispersion medium and the dispersion particles. If the MRF is allowed to stand, the dispersed particles settle in a short time and the stability of the dispersed particles in the dispersion medium is impaired and the MRF function is not achieved. Means for improving the uniformity and stability of dispersion of dispersed particles in MRF have already been developed by the present inventor and presented as Japanese Patent Application No. 2002-231446. That is, as shown in Japanese Patent Application No. 2002-231446 specification / drawing (Patent Document 1), the thixotropy property of the dispersion medium (a high viscosity state is maintained until force or impact is applied from the outside, Dispersed particle non-sedimentation type MRF has been proposed in the past that has been imparted with the property of instantly becoming liquid when added. And as a dispersion medium of thixotropic MRF used there, a liquid smectite bentonite mainly composed of swellable layered clay mineral montmorillonite and an oil liquid such as dioctyl phthalate (abbreviated as “DOP”). And a spherical carbonyl iron powder having a particle size of several μm is used as the dispersed particles. However, the conventional silicone oil used as a dispersion medium has a problem in the dispersion stability of dispersed particles, and the dispersion medium in which DOP is incorporated into Lucentite has a large environmental impact of DOP. There was a problem that the future potential of was concerned.
Japanese Patent Application No. 2002-231446 Specification / Drawings

この発明は、ＤＯＰの環境負荷が大きいことからＭＲＦの実用化段階での将来性が懸念されることに鑑み、これを機に環境負荷の視点に立って、環境問題の懸念を払拭すべく、ルーセンタイトにＤＯＰを取り込ませる分散媒に替わる環境負荷の小さいＭＲＦを得ようとするものである。   In view of the concern about the future potential of the MRF in practical use because the environmental load of DOP is large, this invention is based on this point of view from the viewpoint of environmental load, An attempt is made to obtain an MRF with a low environmental load in place of a dispersion medium in which DOP is incorporated into Lucentite.

上記の課題を解決する手段として、この発明では、不飽和脂肪酸に膨潤性層状粘土鉱物あるいは非水系塗料用垂れ防止剤を添加混合した分散媒中に、強磁性体粉末を分散させて磁気レオロジー流体を生成する。より具体的には、不飽和脂肪酸であるところの菜種油すなわち環境問題が生じない植物性油である菜種油に膨潤性層状粘土鉱物であるところのルーセンタイトあるいは非水系塗料用垂れ防止剤を添加混合した分散媒中に、強磁性体粉末を分散させて磁気レオロジー流体を生成する。また強磁性体粉末として、粒径１〜２０μmの球形カルボニル鉄粉を分散媒中に分散させる。   As a means for solving the above-mentioned problems, in the present invention, a magnetorheological fluid is obtained by dispersing a ferromagnetic powder in a dispersion medium in which a swellable layered clay mineral or a non-aqueous sag-preventing agent is added and mixed with an unsaturated fatty acid. Is generated. More specifically, rapeseed oil, which is an unsaturated fatty acid, that is, rapeseed oil, which is a vegetable oil that does not cause environmental problems, is added and mixed with a swellable layered clay mineral, lucentite or a non-water-based anti-sagging agent for paints. A magnetorheological fluid is produced by dispersing ferromagnetic powder in a dispersion medium. Further, spherical carbonyl iron powder having a particle diameter of 1 to 20 μm is dispersed in a dispersion medium as a ferromagnetic powder.

この発明に係る磁気レオロジー流体は、シリコーン油系分散媒を用いないことから分散粒子の分散安定度（流体の静置経過時間に対する分散粒子の沈下抑制度合）が高く、分散媒の主成分としてＤＯＰに替えて環境負荷の無い不飽和脂肪酸、菜種油を用いるため、環境問題が懸念されない分散粒子無沈降型ＭＲＦとし実用上極めて優れたものである。 Since the magnetorheological fluid according to the present invention does not use a silicone oil-based dispersion medium, the dispersion stability of the dispersed particles is high (the degree of suppression of the settlement of the dispersed particles with respect to the fluid standing time), and DOP is the main component of the dispersion medium. Instead of using an unsaturated fatty acid and rapeseed oil having no environmental impact, the dispersion particle non-sedimentation type MRF which is not concerned about environmental problems is extremely excellent in practical use.

この発明の好ましい実施形態は、不飽和脂肪酸であるところの菜種油に膨潤性層状粘土鉱物であるところのルーセンタイト、あるいは非水系塗料用垂れ防止剤を添加混合した分散媒中に、粒径１〜２０μmのポリマー加工型または表面被覆型の球形カルボニル鉄粉を分散させた磁気レオロジー流体である。   A preferred embodiment of the present invention has a particle size of 1 to 4 in a dispersion medium in which rapeseed oil as an unsaturated fatty acid is mixed with lucentite as a swellable lamellar clay mineral or an anti-sagging agent for non-aqueous paints. Magnetorheological fluid in which 20 μm polymer processed type or surface coated type spherical carbonyl iron powder is dispersed.

以下、この発明の実施例を説明する。例えば、不飽和脂肪酸であるところの菜種油、菜種油エステル、菜種油系油（これらを総じて、この出願においては「菜種油」という）に膨潤性層状粘土鉱物であるところのルーセンタイトをチキソトロピー性添加剤として２０wt％添加混合した分散媒中に、粒径３．６９μmの球形カルボニル鉄粉を３０wt％分散させてＭＲＦ（この発明に係る菜種油ベースＭＲＦ）を生成した。 Examples of the present invention will be described below. For example, rapeseed oil that is an unsaturated fatty acid, rapeseed oil ester, rapeseed oil-based oil (generally referred to as “rapeseed oil” in this application) and lucentite that is a swellable layered clay mineral as a thixotropic additive. In a dispersion medium added and mixed with 30% by weight of spherical carbonyl iron powder having a particle size of 3.69 μm, MRF (rapeseed oil-based MRF according to the present invention) was produced.

そして、この発明に係る上記の菜種油ベースＭＲＦと、シリコーン油に同粒径（粒径３．６９μm）の球形カルボニル鉄粉を３０wt％分散させた従来のＭＲＦ（従来のシリコーン油ベースＭＲＦ）ついて、粒子沈降割合（分散粒子沈降割合）α[%]を測定した結果を図１に示している。すなわち、ＭＲＦをメスシリンダーに高さｈまで注ぎ入れて静置し、時間の経過と共に分散粒子が沈降する距離ｈ’を測定し、その測定値を基に、α＝{(ｈ−Δｈ)／ｈ}×１００[%]，Δｈ＝ｈ−ｈ’で定義したα[%]を図１に示して比較したものである。図１から明らかなように、従来のシリコーン油ベースＭＲＦでは、分散粒子の沈降が著しく、約５０時間経過後には、α＝約２５％まで分散粒子が沈降し、その後にＭＲＦを撹拌しても分散粒子が均一に分散した元のＭＲＦには戻らない。これに対し、この発明に係る菜種油ベースＭＲＦでは、２００時間以上が経過してもαは５％以内に入っており、沈降はそれほど見られず、分散粒子の分散安定性が極めて良いことが分かる。 And about the said rapeseed oil base MRF which concerns on this invention, and conventional MRF (conventional silicone oil base MRF) which disperse | distributed 30 wt% of spherical carbonyl iron powder of the same particle diameter (particle diameter 3.69 micrometer) to silicone oil, The results of measuring the particle sedimentation rate (dispersed particle sedimentation rate) α [%] are shown in FIG. That is, MRF is poured into a graduated cylinder to a height h and allowed to stand, and the distance h ′ at which the dispersed particles settle over time is measured, and α = {(h−Δh) / FIG. 1 shows a comparison of α [%] defined by h} × 100 [%], Δh = h−h ′. As can be seen from FIG. 1, in the conventional silicone oil-based MRF, the settling of the dispersed particles is remarkable, and after about 50 hours, the dispersed particles settle to α = about 25%, and then the MRF is stirred. It does not return to the original MRF in which the dispersed particles are uniformly dispersed. On the other hand, in the rapeseed oil-based MRF according to the present invention, α is within 5% even after 200 hours have passed, so that sedimentation is not seen so much and it is understood that the dispersion stability of the dispersed particles is extremely good. .

次に図２は、分散媒として、ルーセンタイト（ＳＰＮ）を菜種油エステルに対して１８wt％混合し十分撹拌した後に、粒径３．６９μmの球形カルボニル鉄粉をΦ＝８５wt％の比率で混合したこの発明に係るチキソトロピー性ＭＲＦを作動油としてクラッチギャップに充填し、トルク[N・m]−磁界[T(tesla)]特性の回転数依存性を示したもので、回転数が低下するにつれて高トルクが得られ、磁界が約０．２[T]のとき、約９．３[N・m]の最大トルクに達した。 Next, FIG. 2 shows that, as a dispersion medium, 18% by weight of Lucentite (SPN) is mixed with rapeseed oil ester and stirred sufficiently, and then spherical carbonyl iron powder having a particle size of 3.69 μm is mixed at a ratio of Φ = 85% by weight. The thixotropic MRF according to the present invention is filled in the clutch gap as hydraulic oil, and shows the rotational speed dependency of the torque [N · m] -magnetic field [T (tesla)] characteristics. When the torque was obtained and the magnetic field was about 0.2 [T], the maximum torque of about 9.3 [N · m] was reached.

また図３は、分散媒として、ルーセンタイト（ＳＰＮ）を菜種油エステルに対して２０wt％混合し十分撹拌した後に、粒径３．６９μmの球形カルボニル鉄粉の分散媒に混合する割合を１０，３０，５０wt％と変化させて作製したこの発明に係るチキソトロピー性ＭＲＦを作動油としてクラッチギャップに充填し、トルク[N・m]−磁界[T(tesla)]特性の回転数依存性を示したもので、分散粒子である鉄粉濃度が上昇するにつれ高トルクが得られ、磁界が約０．５５[T]ののとき、約７[N・m]の最大トルクに達した。なお、チキソトロピー性を持たないシリコーン油ベースの分散媒にこの鉄粉濃度Φ＝５０wt％で混合して作製したＭＲＦも比較のため併せて図示している。図３から明らかなように、菜種油ベース（Φ＝５０％）でも、動作状態では十分液化が進み、液体シリコーン油とほぼ同等のトルクに達することが分かった。しかし、シリコーン油ベースの分散媒からなるＭＲＦは、先にも記した通り、静置後５０時間程度で分散粒子が沈降してしまった。これに対しこの発明に係るＭＲＦでは、静置２５時間、作動１時間、静置２５時間を４回繰り返しても、ほぼ初期のトルクが再現された。   Further, FIG. 3 shows that as a dispersion medium, 20% by weight of Lucentite (SPN) is mixed with rapeseed oil ester and sufficiently stirred, and then mixed with the dispersion medium of spherical carbonyl iron powder having a particle size of 3.69 μm at 10,30. The thixotropic MRF according to the present invention produced by changing the amount of the oil to 50 wt% is filled in the clutch gap as a working oil, and the torque [N · m] -magnetic field [T (tesla)] characteristics are shown to be dependent on the rotational speed. As the concentration of iron powder as dispersed particles increased, a high torque was obtained, and when the magnetic field was about 0.55 [T], the maximum torque of about 7 [N · m] was reached. An MRF prepared by mixing this silicone powder-based dispersion medium having no thixotropic property at an iron powder concentration of Φ = 50 wt% is also shown for comparison. As is clear from FIG. 3, it was found that even in the rapeseed oil base (Φ = 50%), the liquefaction progressed sufficiently in the operating state, and reached almost the same torque as the liquid silicone oil. However, as described above, in the MRF composed of the silicone oil-based dispersion medium, the dispersed particles settled in about 50 hours after standing. On the other hand, in the MRF according to the present invention, the initial torque was reproduced even when the stationary 25 hours, the operation 1 hour, and the stationary 25 hours were repeated four times.

なお、この発明に係るＭＲＦの生成に当たり、膨潤性層状粘土鉱物であるところのルーセンタイトをチキソトロピー性付与添加物として不飽和脂肪酸・菜種油に混合する割合は、不飽和脂肪酸・菜種油に対して現段階においては、１６〜２４wt％、好ましくは１８〜２２wt％としたが、その混合割合が１６％以下ではチキソトロピー性が付与されず、他方２４％以上では分散媒の粘度が極端に上昇して分散媒として適正を欠く場合があると考えられるからである。また、分散粒子として粒径１〜２０μmの球形カルボニル鉄粉を分散媒中に分散させたが、その粒径が１μm以下では必要とする応力やトルクが得られず、粒径が２０μm以上では分散粒子沈降傾向が現われて適正を欠く場合があると考えられるからである。また球形カルボニル鉄粉として、ポリマー加工型の球形カルボニル鉄粉や表面被覆型の球形カルボニル鉄粉を用いることも有用である。更にまた、不飽和脂肪酸・菜種油に混合するチキソトロピー性付与添加物としては、膨潤性層状粘土鉱物であるところのルーセンタイトのほか、非水系塗料用垂れ防止剤（例えば商品名「ディスパロン」など）を添加することにより好ましい結果が得られる。   In addition, in the production of MRF according to the present invention, the ratio of mixing the scented layered clay mineral, lucentite, into the unsaturated fatty acid / rapeseed oil as a thixotropic additive is the current stage relative to the unsaturated fatty acid / rapeseed oil. However, if the mixing ratio is 16% or less, the thixotropic property is not imparted, and if it is 24% or more, the viscosity of the dispersion medium is extremely increased. This is because it is considered that there may be cases where it is not appropriate. In addition, spherical carbonyl iron powder having a particle size of 1 to 20 μm was dispersed in the dispersion medium as dispersed particles. However, when the particle size was 1 μm or less, required stress and torque could not be obtained, and when the particle size was 20 μm or more, the dispersion was performed. This is because it is thought that there is a case where the tendency of particle sedimentation appears and lacks appropriateness. It is also useful to use a polymer-processed spherical carbonyl iron powder or a surface-coated spherical carbonyl iron powder as the spherical carbonyl iron powder. Furthermore, as thixotropy-imparting additives to be mixed with unsaturated fatty acids and rapeseed oil, in addition to lucentite, which is a swellable layered clay mineral, anti-sagging agents for non-aqueous paints (for example, trade name “DISPARON”, etc.) Addition gives favorable results.

この発明に係る分散粒子無沈降型ＭＲＦを構成する分散媒は、不飽和脂肪酸を主成分とする、例えば、菜種油や菜種油系油を、ケイ酸塩からなるルーセンタイトの層間に取り込ませたものである。その層間は、ファン・デル・ワールス力のように弱く結合しており、機械的に衝撃を与えると直ちに破壊されて液状化するが、一定時間静置すると再び結合しゲル化する特徴がある。ケイ酸塩は、４価もしくは３価の陽イオンを持つ２枚の４面体シートの間に３価もしくは２価の陽イオンを持つ８面体シートが挟まれた構造を有し、したがって、陽イオン１個が不足した状態となっている。そこで４面体−４面体の層間に１価の陽イオンを取り込み電気的中性が保たれる構造となっている。その層間距離は、通常nm程度であり、１価の特定のサイズを持つ陽イオンが取り込まれる。この発明によって、ＤＯＰに次いで菜種油がこの条件を満たすことが見出されたのである。この発明に係るＭＲＦは、チキソトロピー性を持つ分散媒であるため、外部から力や衝撃が加わらない限り、分散粒子は高粘度の分散媒（ゲル）中に保持されており、分散媒と分散粒子の各密度に差があっても、長時間にわたり沈降を生じさせない作用効果をもたらす。そして、このＭＲＦに磁界を印加して起動させる際には、ＭＲＦに力や衝撃を加えることによって瞬時に液状化してＭＲ効果が生ずる。その上でこの発明に係るＭＲＦは、経時変化が全く生じないので、流体の信頼性を長期にわたって保持でき、更に環境に優しい植物油の菜種油・菜種油系油を用いるので、将来にわたって安心して使用できるＭＲＦである。 The dispersion medium constituting the dispersed particle non-sediment type MRF according to the present invention is composed of an unsaturated fatty acid as a main component, for example, rapeseed oil or rapeseed oil-based oil incorporated between silicate-based lucentite layers. is there. The layers are weakly bonded like van der Waals force, and when they are mechanically impacted, they are immediately destroyed and liquefied, but when left standing for a certain period of time, they are combined and gelled again. Silicate has a structure in which an octahedral sheet having a trivalent or divalent cation is sandwiched between two tetrahedral sheets having a tetravalent or trivalent cation. One is missing. Therefore, a monovalent cation is introduced between the tetrahedron and tetrahedron layers so that electrical neutrality is maintained. The interlayer distance is usually about nm, and cations having a specific monovalent size are taken in. According to this invention, rapeseed oil was found to satisfy this condition after DOP. Since the MRF according to the present invention is a dispersion medium having thixotropy, the dispersion particles are held in a highly viscous dispersion medium (gel) unless external force or impact is applied. Even if there is a difference in each density, an effect that does not cause sedimentation over a long period of time is brought about. When the magnetic field is applied to the MRF and activated, an MR effect is generated by liquefying instantaneously by applying a force or impact to the MRF. In addition, since the MRF according to the present invention does not change over time, the reliability of the fluid can be maintained over a long period of time, and the rapeseed oil / rapeseed oil-based oil, which is more environmentally friendly, is used. It is.

この発明に係る磁気レオロジー流体は、上記のように、シリコン油系分散媒を用いないことから分散粒子の分散安定度（流体の静置経過時間に対する分散粒子の沈下抑制度合）が高く、分散媒の主成分としてＤＯＰに替えて環境負荷の無い不飽和脂肪酸、菜種油を用いるため、環境問題が懸念されない分散粒子無沈降型ＭＲＦとして、ＭＲＦの実用化を促進し、従来のＭＲＦの用途を含め、クラッチ、ブレーキなどの動力伝達装置・駆動装置、緩衝装置、振動制御装置、免震装置など、各種の用途に幅広く利用可能である。 Since the magnetorheological fluid according to the present invention does not use a silicone oil-based dispersion medium as described above, the dispersion stability of the dispersed particles (the degree of suppression of the settlement of the dispersed particles with respect to the fluid standing time) is high. Since the unsaturated fatty acid and rapeseed oil, which have no environmental impact, are used instead of DOP as the main component, the practical use of MRF is promoted as a dispersed particle non-sedimented MRF that is not concerned about environmental problems, including the use of conventional MRF, It can be widely used for various applications such as power transmission devices and drive devices such as clutches and brakes, shock absorbers, vibration control devices, and seismic isolation devices.

この発明に係るＭＲＦと従来のＭＲＦの、静置経過時間に対する分散粒子沈降割合変化特性図。The dispersion | distribution particle sedimentation ratio change characteristic view with respect to stationary elapsed time of MRF which concerns on this invention, and conventional MRF. この発明に係るＭＲＦをクラッチ作動油として用いた場合の磁界−トルク特性図。The magnetic field-torque characteristic view at the time of using MRF concerning this invention as clutch operation oil. この発明に係るＭＲＦをクラッチ作動油として用いた場合の分散粒子濃度−トルク特性図。The dispersion | distribution particle concentration-torque characteristic view at the time of using MRF concerning this invention as clutch hydraulic fluid.

符号の説明Explanation of symbols

α：分散粒子沈降割合
ｔ：ＭＥＦの静置経過時間
Ｎ・：トルク単位／ニュートン・メータ
Ｔ：磁界単位／テスラ
α: Dispersed particle sedimentation ratio t: MEF stationary elapsed time N ·: Torque unit / Newton meter T: Magnetic field unit / Tesla

Claims (5)

不飽和脂肪酸に膨潤性層状粘土鉱物あるいは非水系塗料用垂れ防止剤を添加混合した分散媒中に、強磁性体粉末を分散させてなることを特徴とする磁気レオロジー流体。 A magnetorheological fluid comprising a ferromagnetic powder dispersed in a dispersion medium in which a swellable layered clay mineral or a non-aqueous anti-sagging agent is added to an unsaturated fatty acid. 不飽和脂肪酸であるところの菜種油に膨潤性層状粘土鉱物であるところのルーセンタイトを添加混合した分散媒中に、強磁性体粉末を分散させてなることを特徴とする磁気レオロジー流体。 A magnetorheological fluid obtained by dispersing a ferromagnetic powder in a dispersion medium obtained by adding and mixing rapeseed oil, which is an unsaturated fatty acid, with lucentite, which is a swellable layered clay mineral. 不飽和脂肪酸であるところの菜種油に非水系塗料用垂れ防止剤を添加混合した分散媒中に、強磁性体粉末を分散させてなることを特徴とする磁気レオロジー流体。 A magnetorheological fluid characterized by dispersing a ferromagnetic powder in a dispersion medium obtained by adding and mixing a rapeseed oil, which is an unsaturated fatty acid, with an anti-sagging agent for non-aqueous paints. 分散媒中に球形カルボニル鉄粉を分散させたことを特徴とする請求項１ないし請求項３のいずれか１項に記載の磁気レオロジー流体。 The magnetorheological fluid according to any one of claims 1 to 3, wherein spherical carbonyl iron powder is dispersed in a dispersion medium. 分散媒中に粒径１〜２０μmの球形カルボニル鉄粉を分散させたことを特徴とする請求項１ないし請求項４のいずれか１項に記載の磁気レオロジー流体。
5. The magnetorheological fluid according to claim 1, wherein spherical carbonyl iron powder having a particle diameter of 1 to 20 μm is dispersed in a dispersion medium.
JP2004049971A 2004-02-25 2004-02-25 Magnetorheological fluid Pending JP2005243811A (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100734333B1 (en) 2006-03-17 2007-07-02 주식회사 모두테크놀로지 Magnetorheological fluid having good dispersibility and re-dispersibility
CN103003372A (en) * 2010-07-09 2013-03-27 埃卡特有限公司 Lamina-like iron pigments, magnetorheological fluid and device
JP2013181598A (en) * 2012-03-01 2013-09-12 Kurimoto Ltd Magnetic viscous fluid and clutch using the same
JP2014033150A (en) * 2012-08-06 2014-02-20 Kanazawa Inst Of Technology Magnetic rheology fluid
CN103897789A (en) * 2014-04-17 2014-07-02 吉林大学 Magnetorheological fluid comprising macromolecular composite magnetic powder and preparation method thereof

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100734333B1 (en) 2006-03-17 2007-07-02 주식회사 모두테크놀로지 Magnetorheological fluid having good dispersibility and re-dispersibility
CN103003372A (en) * 2010-07-09 2013-03-27 埃卡特有限公司 Lamina-like iron pigments, magnetorheological fluid and device
CN103003372B (en) * 2010-07-09 2015-04-15 埃卡特有限公司 Lamina-like iron pigments, magnetorheological fluid and device
JP2013181598A (en) * 2012-03-01 2013-09-12 Kurimoto Ltd Magnetic viscous fluid and clutch using the same
JP2014033150A (en) * 2012-08-06 2014-02-20 Kanazawa Inst Of Technology Magnetic rheology fluid
CN103897789A (en) * 2014-04-17 2014-07-02 吉林大学 Magnetorheological fluid comprising macromolecular composite magnetic powder and preparation method thereof

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