JPS63124402A - Fluorine-based magnetic fluid composition and manufacture thereof - Google Patents
Fluorine-based magnetic fluid composition and manufacture thereofInfo
- Publication number
- JPS63124402A JPS63124402A JP61270594A JP27059486A JPS63124402A JP S63124402 A JPS63124402 A JP S63124402A JP 61270594 A JP61270594 A JP 61270594A JP 27059486 A JP27059486 A JP 27059486A JP S63124402 A JPS63124402 A JP S63124402A
- Authority
- JP
- Japan
- Prior art keywords
- fine particles
- magnetic fluid
- solvent
- fluid composition
- intermediate medium
- 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.)
- Pending
Links
- 239000011553 magnetic fluid Substances 0.000 title claims abstract description 50
- 229910052731 fluorine Inorganic materials 0.000 title claims abstract description 27
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 title claims abstract description 26
- 239000011737 fluorine Substances 0.000 title claims abstract description 26
- 239000000203 mixture Substances 0.000 title claims description 51
- 238000004519 manufacturing process Methods 0.000 title claims description 25
- 230000005294 ferromagnetic effect Effects 0.000 claims abstract description 64
- 239000002904 solvent Substances 0.000 claims abstract description 58
- 239000004094 surface-active agent Substances 0.000 claims abstract description 44
- 238000009835 boiling Methods 0.000 claims abstract description 42
- 239000010702 perfluoropolyether Substances 0.000 claims abstract description 42
- 239000002245 particle Substances 0.000 claims abstract description 40
- 150000003839 salts Chemical class 0.000 claims abstract description 21
- 238000001704 evaporation Methods 0.000 claims abstract description 8
- 238000010438 heat treatment Methods 0.000 claims abstract description 6
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 claims abstract 2
- 239000010419 fine particle Substances 0.000 claims description 60
- 239000002609 medium Substances 0.000 claims description 39
- 239000002612 dispersion medium Substances 0.000 claims description 18
- 239000003921 oil Substances 0.000 claims description 13
- -1 perfluoro Chemical group 0.000 claims description 8
- 239000000725 suspension Substances 0.000 claims description 7
- 239000000126 substance Substances 0.000 claims description 3
- 239000006185 dispersion Substances 0.000 abstract description 6
- 239000000084 colloidal system Substances 0.000 abstract description 5
- 239000003302 ferromagnetic material Substances 0.000 abstract description 4
- 239000006249 magnetic particle Substances 0.000 abstract description 4
- 239000002131 composite material Substances 0.000 abstract description 2
- 239000002270 dispersing agent Substances 0.000 abstract description 2
- 229910018830 PO3H Inorganic materials 0.000 abstract 1
- SZVJSHCCFOBDDC-UHFFFAOYSA-N iron(II,III) oxide Inorganic materials O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 description 22
- 238000000034 method Methods 0.000 description 11
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 10
- TXEYQDLBPFQVAA-UHFFFAOYSA-N tetrafluoromethane Chemical compound FC(F)(F)F TXEYQDLBPFQVAA-UHFFFAOYSA-N 0.000 description 8
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- 239000000243 solution Substances 0.000 description 6
- 239000007864 aqueous solution Substances 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- 239000007788 liquid Substances 0.000 description 4
- 229910000859 α-Fe Inorganic materials 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 230000008020 evaporation Effects 0.000 description 3
- NBVXSUQYWXRMNV-UHFFFAOYSA-N fluoromethane Chemical compound FC NBVXSUQYWXRMNV-UHFFFAOYSA-N 0.000 description 3
- 230000001050 lubricating effect Effects 0.000 description 3
- 230000005291 magnetic effect Effects 0.000 description 3
- 230000005415 magnetization Effects 0.000 description 3
- VLKZOEOYAKHREP-UHFFFAOYSA-N n-Hexane Chemical compound CCCCCC VLKZOEOYAKHREP-UHFFFAOYSA-N 0.000 description 3
- 238000010298 pulverizing process Methods 0.000 description 3
- 239000006228 supernatant Substances 0.000 description 3
- 238000005406 washing Methods 0.000 description 3
- 239000004215 Carbon black (E152) Substances 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 150000001732 carboxylic acid derivatives Chemical class 0.000 description 2
- 238000005119 centrifugation Methods 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 229910017052 cobalt Inorganic materials 0.000 description 2
- 239000010941 cobalt Substances 0.000 description 2
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 2
- 239000003792 electrolyte Substances 0.000 description 2
- 239000011790 ferrous sulphate Substances 0.000 description 2
- 235000003891 ferrous sulphate Nutrition 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 229930195733 hydrocarbon Natural products 0.000 description 2
- 150000002430 hydrocarbons Chemical class 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 description 2
- RUTXIHLAWFEWGM-UHFFFAOYSA-H iron(3+) sulfate Chemical compound [Fe+3].[Fe+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O RUTXIHLAWFEWGM-UHFFFAOYSA-H 0.000 description 2
- 229910000359 iron(II) sulfate Inorganic materials 0.000 description 2
- 229910000360 iron(III) sulfate Inorganic materials 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 238000007789 sealing Methods 0.000 description 2
- 239000002002 slurry Substances 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 1
- VTLYFUHAOXGGBS-UHFFFAOYSA-N Fe3+ Chemical compound [Fe+3] VTLYFUHAOXGGBS-UHFFFAOYSA-N 0.000 description 1
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 239000003929 acidic solution Substances 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000013016 damping Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 229910001447 ferric ion Inorganic materials 0.000 description 1
- 229910001448 ferrous ion Inorganic materials 0.000 description 1
- 239000000706 filtrate Substances 0.000 description 1
- 238000007667 floating Methods 0.000 description 1
- 125000001153 fluoro group Chemical group F* 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 125000004435 hydrogen atom Chemical group [H]* 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- 238000005461 lubrication Methods 0.000 description 1
- 230000005389 magnetism Effects 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 239000011572 manganese Substances 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 125000000896 monocarboxylic acid group Chemical group 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- AJCDFVKYMIUXCR-UHFFFAOYSA-N oxobarium;oxo(oxoferriooxy)iron Chemical compound [Ba]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O AJCDFVKYMIUXCR-UHFFFAOYSA-N 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 239000000565 sealant Substances 0.000 description 1
- 239000003566 sealing material Substances 0.000 description 1
- 238000004062 sedimentation Methods 0.000 description 1
- 229910052596 spinel Inorganic materials 0.000 description 1
- 239000011029 spinel Substances 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 125000000876 trifluoromethoxy group Chemical group FC(F)(F)O* 0.000 description 1
- 238000001238 wet grinding Methods 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/44—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of magnetic liquids, e.g. ferrofluids
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
この発明は、強磁性体微粒子をフッ素系の溶媒中に安定
に分散せしめた磁性流体組成物とその製造方法に関する
。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic fluid composition in which fine ferromagnetic particles are stably dispersed in a fluorine-based solvent, and a method for producing the same.
磁性流体は、マグネタイト、フェライト、鉄。 Magnetic fluids include magnetite, ferrite, and iron.
コバルトなどの強磁性体微粒子が液体中に分散する極め
て安定したコロイド溶液であり、その液体自体が見掛は
上強い磁性を示すという特性を有する。従って液体であ
りながら磁石等によりその挙動を自在に拘束できるから
、ダンピング剤とか磁気ディスク等のシール機構におけ
るシーリング剤その他、応用分野は多岐にわたっている
。It is an extremely stable colloidal solution in which fine particles of ferromagnetic material such as cobalt are dispersed in a liquid, and the liquid itself has the property of apparently exhibiting strong magnetism. Therefore, although it is a liquid, its behavior can be restrained freely by magnets, etc., so it has a wide range of applications, including as a damping agent and a sealing agent in sealing mechanisms for magnetic disks and the like.
而して、その応用分野によって要求される仕様・性能が
異なり、中には低トルク、耐寒性、耐薬品性、絶縁性で
あることに加え、更に水にも炭化水素系油にも相溶性の
ないことが要求される場合かある。The specifications and performance required vary depending on the field of application, including low torque, cold resistance, chemical resistance, and insulation, as well as compatibility with water and hydrocarbon oils. There are cases where it is required not to have one.
このような要求に対しては、従来一般の炭化水素系溶媒
を分散媒とした磁性流体では対応しきれない。そこでパ
ーフルオロ系溶媒を分散媒としたものが提案されている
（米国特許３，７８４，４７１）。これは、パーフルオ
ロ系溶媒を分散媒として、その分散媒内に強磁性体微粒
子を安定に分散させるのに、フルオロカーボン系の界面
活性剤を用いたものである。すなわち、分散媒は一般式
（式中のＡはフッ素原子または水素原子 ）で示される
パーフルオロポリエーテルであり、これに対して強磁性
体微粒子の分散安定剤としては、例えば式
で示されるフルオロカーボン系の界面活性剤を用いてい
る。Such demands cannot be met with conventional magnetic fluids using general hydrocarbon solvents as dispersion media. Therefore, a method using a perfluorinated solvent as a dispersion medium has been proposed (US Pat. No. 3,784,471). This uses a perfluoro-based solvent as a dispersion medium and uses a fluorocarbon-based surfactant to stably disperse ferromagnetic fine particles in the dispersion medium. That is, the dispersion medium is a perfluoropolyether represented by the general formula (A in the formula is a fluorine atom or a hydrogen atom), whereas the dispersion stabilizer for ferromagnetic fine particles is, for example, a fluorocarbon represented by the formula A type of surfactant is used.
しかしながら、上記一般式で示される従来のフルオロカ
ーボン系の界面活性剤を、優れた潤滑特性を持つ分散媒
であるパーフルオロポリエーテル油
Ｆ ３
■
ＣＦ３ ［（ＯＣＦ ＣＦＺ）ｌｌ （ＯＣＦ
２）−］ ＯＣＦ３ 、 （ｎ：ｍ＝４０ ：
１）に対して用いると、両者の構造が異なるため親和
性が低下して、強磁性体微粒子の分散が不安定になると
いう問題点があった。However, the conventional fluorocarbon surfactant represented by the above general formula is replaced by perfluoropolyether oil F3 ■ CF3 [(OCF CFZ)ll (OCF
2)-]OCF3, (n:m=40:
When used for 1), there was a problem in that the two structures were different, so the affinity decreased and the dispersion of the ferromagnetic fine particles became unstable.
この発明はこのような従来の問題点に着目してなされた
ものであり、構造式
％式％
：１）
で示されるパーフルオロポリエーテル油を分散媒とし、
これに強磁性体微粒子を分散させるための界面活性剤に
は、パーフルオロポリエーテル部の構造が同一であるパ
ーフルオロポリエーテル誘導体を用いることにより、高
い分散安定性を付与せしめたフッ素系磁性流体組成物と
その製造方法を提供することを目的としている。This invention was made by focusing on such conventional problems, and uses perfluoropolyether oil represented by the structural formula %:1) as a dispersion medium,
A fluorinated magnetic fluid with high dispersion stability is used as a surfactant for dispersing the ferromagnetic fine particles by using a perfluoropolyether derivative with the same perfluoropolyether structure. The object of the present invention is to provide a composition and a method for producing the same.
この発明の組成物は、パーフルオロ系溶媒中に、強磁性
体微粒子を、界面活性剤を介して安定に分散させてなる
フッ素系磁性流体組成物において、前記界面活性剤は一
般式
％式％）
（式中のＲは、 ＣＯＯＨ、ＣＨｚ ＯＨ。The composition of the present invention is a fluorinated magnetic fluid composition in which fine ferromagnetic particles are stably dispersed in a perfluorinated solvent via a surfactant, wherein the surfactant has the general formula %. ) (R in the formula is COOH, CHz OH.
ＯＨ、Ｓ Ｏｓ ＯＨ、Ｐ Ｏｓ Ｈ。OH, S Os OH, P Os H.
−ＮＨ２などの群から選ばれた極性基
である）
で示すれるパーフルオロポリエーテル誘導体又はこれら
の塩のうちの少なくとも一種であることを特徴とするフ
ッ素系磁性流体組成物である。A fluorine-based magnetic fluid composition characterized in that it is at least one of the perfluoropolyether derivatives or salts thereof represented by the following formula (a polar group selected from the group of -NH2, etc.).
またこの発明の製造方法は、強磁性体微粒子にパーフル
オロポリエーテル誘導体又はこれらの塩からなる界面活
性剤とパーフルオロ系低沸点溶媒とを加え、表面を前記
界面活性剤で被覆した強磁性体微粒子が低沸点溶媒中に
分散された中間媒体を得る工程と、該中間媒体中の分散
性の悪い微粒子を分離した後パーフルオロ系溶媒を中間
媒体に加えて混合物とする工程と、該混合物を加熱し前
記低沸点溶媒を蒸発させる工程とを包含するフッ素系磁
性流体組成物の製造方法である。Further, the manufacturing method of the present invention includes adding a surfactant made of a perfluoropolyether derivative or a salt thereof and a perfluoro-based low boiling point solvent to ferromagnetic fine particles, and producing a ferromagnetic material whose surface is coated with the surfactant. a step of obtaining an intermediate medium in which fine particles are dispersed in a low-boiling point solvent; a step of separating fine particles with poor dispersibility in the intermediate medium and then adding a perfluoro solvent to the intermediate medium to form a mixture; The method for producing a fluorine-based magnetic fluid composition includes the step of heating and evaporating the low boiling point solvent.
更にまた、この発明の他の製造方法は、強磁性体微粒子
にパーフルオロポリエーテル誘導体又はこれらの塩から
なる界面活性剤とパーフルオロ系低沸点溶媒とを加え、
表面を前記界面活性剤で被覆した強磁性体微粒子が低沸
点溶媒中に分散された中間媒体を得る工程と、該中間媒
体中の分散性の悪い微粒子を分離した後中間媒体を加熱
し前記低沸点溶媒を蒸発させる工程と、該工程を経た強
磁性体微粒子にパーフルオロ系溶媒を加える工程とを包
含するフッ素系磁性流体組成物の製造方法である。Furthermore, another manufacturing method of the present invention includes adding a surfactant made of a perfluoropolyether derivative or a salt thereof and a perfluoro-based low boiling point solvent to ferromagnetic fine particles,
A step of obtaining an intermediate medium in which ferromagnetic fine particles whose surface is coated with the surfactant is dispersed in a low boiling point solvent, and after separating fine particles with poor dispersibility in the intermediate medium, heating the intermediate medium and dispersing the low boiling point solvent. This is a method for producing a fluorine-based magnetic fluid composition, which includes a step of evaporating a boiling point solvent and a step of adding a perfluoro-based solvent to the ferromagnetic fine particles that have undergone the step.
なお、具体的には、この発明の製造方法は、強磁性体微
粒子にパーフルオロポリエーテル誘導体又はこれらの塩
からなる界面活性剤を加えて強磁性体微粒子の表面を前
記界面活性剤で被覆し、該被覆した強磁性体微粒子にパ
ーフルオロ系低沸点溶媒を加えて中間媒体を得るフッ素
系磁性流体組成物の製造方法である。Specifically, the manufacturing method of the present invention includes adding a surfactant made of a perfluoropolyether derivative or a salt thereof to ferromagnetic fine particles, and coating the surface of the ferromagnetic fine particles with the surfactant. , is a method for producing a fluorine-based magnetic fluid composition, in which an intermediate medium is obtained by adding a perfluorinated low-boiling point solvent to the coated ferromagnetic fine particles.
また、強磁性体微粒子にパーフルオロ系低沸点溶媒を加
えて懸濁液とし、該懸濁液にパーフルオロポリエーテル
誘導体又はこれらの塩からなる界面活性剤を加えて中間
媒体を得るフッ素系磁性流体組成物の製造方法である。In addition, a perfluorinated low-boiling point solvent is added to ferromagnetic fine particles to form a suspension, and a surfactant consisting of a perfluoropolyether derivative or a salt thereof is added to the suspension to obtain an intermediate medium. A method for producing a fluid composition.
また、強磁性体微粒子にパーフルオロポリエーテル誘導
体又はこれらの塩からなる界面活性剤とパーフルオロ系
低沸点溶媒との混合液を加えて中間媒体を得るフッ素系
磁性流体組成物の製造法である。In addition, there is a method for producing a fluorinated magnetic fluid composition in which an intermediate medium is obtained by adding a mixture of a surfactant made of a perfluoropolyether derivative or a salt thereof and a perfluorinated low-boiling solvent to ferromagnetic fine particles. .
また、パーフルオロポリエーテル誘導体又はこれらの塩
からなる界面活性剤は強磁性体微粒子表面に単分子層を
形成することのできる量だけ添加するフッ素系磁性流体
組成物の製造方法である。Another method is to produce a fluorinated magnetic fluid composition in which a surfactant made of a perfluoropolyether derivative or a salt thereof is added in an amount sufficient to form a monomolecular layer on the surface of the ferromagnetic fine particles.
また、所望のパーフルオロ系溶媒を分散媒とした磁性流
体を生成してから分散性の悪い微粒子を除去し、次いで
該磁性流体を中間媒体に加えて混合物とするフッ素系磁
性流体組成物の製造方法である。In addition, a fluorine-based magnetic fluid composition is produced by producing a magnetic fluid using a desired perfluorinated solvent as a dispersion medium, removing fine particles with poor dispersibility, and then adding the magnetic fluid to an intermediate medium to form a mixture. It's a method.
この発明の磁性流体の分散剤として用いるパーフルオロ
ポリエーテル油は、潤滑特性が優れ、また十分に不活性
、不揮発性で真空特性も優れていることから、航空宇宙
用の潤滑剤、シール材として好適に利用されている。そ
こでこれを分散媒として用いると共に、その中に強磁性
体微粒子を分散せしめる界面活性剤として、パーフルオ
ロポリエーテル部の構造が同一のパーフルオロポリエー
テル誘導体又はこれらの塩を利用することにより、低蒸
気圧で、潤滑特性も良く、且つ極めて分散安定性にも優
れた、航空宇宙用シーリング材等に最適のフッ素系磁性
流体が得られる。The perfluoropolyether oil used as a dispersant for the magnetic fluid of this invention has excellent lubricating properties, is sufficiently inert and nonvolatile, and has excellent vacuum properties, so it can be used as a lubricant and sealing material for aerospace applications. It is suitably used. Therefore, by using this as a dispersion medium and a perfluoropolyether derivative or a salt thereof having the same structure of the perfluoropolyether moiety as a surfactant for dispersing the ferromagnetic fine particles in the dispersion medium, it is possible to A fluorine-based magnetic fluid that has low vapor pressure, good lubrication properties, and extremely excellent dispersion stability can be obtained, making it ideal for aerospace sealants and the like.
以下、この発明のフッ素系磁性流体組成物とその製造法
を詳細に説明する。Hereinafter, the fluorine-based magnetic fluid composition of the present invention and its manufacturing method will be explained in detail.
この発明の磁性流体の分散媒として用いるパーフルオロ
系溶媒は、極めて低蒸気圧で且つ優れた潤滑特性を有す
るパーフルオロポリエーテル油であり、その構造式は
Ｆ ３
ＣＦ３ ［（ＯＣＦ ＣＦｚ）−（ＯＣＦ２）ＴＩ］
−〇−ＣＦ３ 、 （ｎ ：ｍ＝４０ ： １）
で示される。The perfluorinated solvent used as a dispersion medium for the magnetic fluid of this invention is a perfluoropolyether oil having an extremely low vapor pressure and excellent lubricating properties, and its structural formula is F 3 CF 3 [(OCF CFz)-( OCF2)TI]
-〇-CF3, (n:m=40:1)
It is indicated by.
この発明の強磁性体微粒子としては、湿式法により得ら
れるマグネタイトコロイドを用い得る。As the ferromagnetic fine particles of this invention, magnetite colloid obtained by a wet method can be used.
ここεこ湿式法とは、第１鉄イオンと第２鉄イオンを１
；２の割合で含む酸性溶液にアルカリを加えてｐＨ９程
度以上とし、適宜な温度下で熟成することによりマグネ
タイトコロイドを得るものである。また、水もしくは溶
媒中でマグネタイト粉末をボールミルで粉砕する、いわ
ゆる湿式粉砕法で得られるものでもよい。The wet method here means that ferrous ions and ferric ions are
A magnetite colloid is obtained by adding an alkali to an acidic solution containing a ratio of 1:2 to 1:2 to adjust the pH to about 9 or more, and aging at an appropriate temperature. Alternatively, it may be obtained by a so-called wet pulverization method in which magnetite powder is pulverized in water or a solvent using a ball mill.
湿式粉砕法を利用する場合、研削液として水辺外に例え
ばヘキサン等の有機溶媒を用いるときは、強磁性体粉末
とその粒子表面に単分子層を形成できる量の界面活性剤
を加えたうえでボールミル中で数時間以上粉砕してもよ
い。When using the wet grinding method, when using an organic solvent such as hexane outside the water as the grinding fluid, add ferromagnetic powder and an amount of surfactant that can form a monomolecular layer on the particle surface. It may be ground in a ball mill for several hours or more.
また、マグネタイト以外のマンガンフェライト。Also, manganese ferrite other than magnetite.
コバルトフェライトもしくはこれらと亜鉛、ニッケルと
の複合フェライトやバリウムフェライトなどの強磁性酸
化物または鉄、コバルト６希土類などの強磁性金属を用
いることもできる。Ferromagnetic oxides such as cobalt ferrite or composite ferrites of these with zinc and nickel, barium ferrite, or ferromagnetic metals such as iron and cobalt-6 rare earths can also be used.
更にまた、強磁性体微粒子として上記湿式性成いは湿式
粉砕法によるもののほか、乾式法で得たものを用いるこ
ともできる。Furthermore, as the ferromagnetic fine particles, in addition to those obtained by the above-mentioned wet method or wet pulverization method, those obtained by a dry method can also be used.
この発明の強磁性体微粒子の粒径は、２０〜５００人の
間にある。例えばマグネタイトは格子定数約８人の単位
格子で逆スピネル構造をとり、結晶は単位格子が数個以
上でなりたつから、少なくとも２０Å以上の粒子径が必
要となる。一方粒子径の上限については、磁性粒子の懸
濁液としての磁性流体の安定性の見地からみると、λ＝
ＭＳ”ｙ ２ ／ ｄ ’ ｋ Ｔで表されるパラメー
タλΦ値が重要となる。（ここにＭＳ：飽和磁化、Ｖ二
粒子の体積、ｄ：粒子の直径、に：ボルソマン定数。The particle size of the ferromagnetic fine particles of this invention is between 20 and 500. For example, magnetite has an inverted spinel structure with a unit cell having a lattice constant of about 8 people, and since a crystal consists of several or more unit cells, a particle size of at least 20 Å is required. On the other hand, regarding the upper limit of the particle size, from the viewpoint of the stability of the magnetic fluid as a suspension of magnetic particles, λ=
The parameter λΦ value expressed as MS"y2/d'kT is important. (where MS: saturation magnetization, V2 particle volume, d: particle diameter, and N: Bolsomann's constant.
Ｔ：絶対温度）。一般に、粒子表面に吸着形成された界
面活性剤層の反発力によって、粒子間引力及び磁性粒子
のもつ磁気双極子間引力に抗して凝集を防止できる限界
値はλ−１０″とされる。そこで今、安全を見積りλ−
１０”とし、かつ飽和磁化ＭＳ＝４００Ｇとすると、上
式により求める粒子径ｄの上限は５００人である。もっ
とも、望まし粒径は１００人前後である。この場合には
上式に於けるるＭ ｓ ＝ ４００ Ｇのときλ−１と
なり、分散磁性微粒子は長時間静置しても沈降するおそ
れはない。T: absolute temperature). Generally, the limit value at which agglomeration can be prevented by resisting interparticle attraction and magnetic dipole attraction of magnetic particles by the repulsive force of a surfactant layer adsorbed and formed on the particle surface is set to λ-10''. Therefore, we now estimate the safety λ−
10'' and saturation magnetization MS = 400G, the upper limit of the particle diameter d determined by the above formula is 500.However, the desirable particle size is around 100.In this case, in the above formula, When M s = 400 G, it becomes λ-1, and there is no fear that the dispersed magnetic fine particles will settle even if they are left standing for a long time.
この発明の強磁性体微粒子の含有量は、従来−般的に用
いられている体積比で１〜２０％の範囲は勿論のこと、
必要に応じて３０％程度の高濃度のものであってもよい
。すなわち、この発明によれば、後述するように強磁性
体微粒子が低沸点溶媒中に分散された中間媒体を利用す
ることで、強磁性体微粒子濃度を３０％に達する高濃度
に調整することができる。こにより、磁化量の極めて高
い磁性流体が得られるものである。The content of the ferromagnetic fine particles of the present invention is of course in the conventionally generally used range of 1 to 20% by volume;
If necessary, the concentration may be as high as about 30%. That is, according to the present invention, the concentration of ferromagnetic particles can be adjusted to a high concentration of up to 30% by using an intermediate medium in which ferromagnetic particles are dispersed in a low boiling point solvent, as described later. can. This makes it possible to obtain a magnetic fluid with extremely high magnetization.
この発明における強磁性体微粒子を前記パーフルオロポ
リエーテル油からなる溶媒中に安定に分散させるための
添加剤は、一般式
％式％）
で示されるパーフルオロポリエーテル誘導体で、式中の
Ｒは、−ＣＯ○Ｈ、ＣＨ２０Ｈ、ＯＨ。The additive for stably dispersing the ferromagnetic fine particles in the solvent of perfluoropolyether oil in this invention is a perfluoropolyether derivative represented by the general formula (%), where R is , -CO○H, CH20H, OH.
Ｓ Ｏ、ｌＯＨ、Ｐ Ｏ３Ｈ、Ｎ Ｈｚなどの群から選
ばれた極性基を有する誘導体又はこれらの塩であり、そ
れらの内の少なくとも一種を選択して用いる。It is a derivative having a polar group selected from the group of S 2 O, 1OH, P 3 O3H, N 2 Hz, etc., or a salt thereof, and at least one of them is selected and used.
この発明のフッ素系磁性流体組成物を製造する方法は、
強磁性体微粒子と界面活性剤とをまず低沸点のパーフル
オロ系溶媒に加えて、表面を界面活性剤で被覆した強磁
性体微粒子がその低沸点燈媒中に分散された中間媒体を
得るものである。次にその中間媒体中の分散性の悪い微
粒子を、例えば５０００〜８０００Ｇで遠心分離して除
く。その後、分散媒としてのパーフルオロポリエーテル
油を加えて混合し、次いでその混合物を加熱して低沸点
のパーフルオロ系溶媒を蒸発除去するか、或いはまた中
間媒体を加熱して低沸点パーフルオロ系溶媒を蒸発させ
てから磁性流体微粒子に分散媒を加えることで、高濃度
で且つ極めて安定した磁性粒子コロイド溶液とするもの
である。The method for producing the fluorine-based magnetic fluid composition of the present invention includes:
First, ferromagnetic fine particles and a surfactant are added to a low boiling point perfluorinated solvent to obtain an intermediate medium in which ferromagnetic fine particles whose surfaces are coated with a surfactant are dispersed in the low boiling point lighting medium. It is. Next, fine particles with poor dispersibility in the intermediate medium are removed by centrifugation at, for example, 5,000 to 8,000 G. Then, perfluoropolyether oil as a dispersion medium is added and mixed, and the mixture is then heated to evaporate the low-boiling perfluorinated solvent, or alternatively, the intermediate medium is heated to remove the low-boiling perfluorinated solvent. By adding a dispersion medium to the magnetic fluid particles after evaporating the solvent, a highly concentrated and extremely stable magnetic particle colloidal solution is obtained.
前記中間媒体の状態で強磁性体微粒子は、分散性のよい
ものと悪いものとが選別される。この選別を繰り返せば
、中間媒体中の強磁性体微粒子の濃度はかなり減少する
が、中間媒体は容易に蒸発させて濃縮させ得るので、濃
縮したものに別の新たな中間媒体を加え、これをまた濃
縮することを繰り返し、分散媒としてのパーフルオロポ
リエーテル油に混合することによって、多量の強磁性体
微粒子を磁性流体中に分散させることが可能となる。In the state of the intermediate medium, the ferromagnetic fine particles are sorted into those with good dispersibility and those with poor dispersibility. If this sorting is repeated, the concentration of ferromagnetic fine particles in the intermediate medium will decrease considerably, but since the intermediate medium can be easily evaporated and concentrated, another new intermediate medium is added to the concentrated medium, and this Further, by repeating the concentration and mixing with perfluoropolyether oil as a dispersion medium, it becomes possible to disperse a large amount of ferromagnetic fine particles in the magnetic fluid.
もし、このような中間媒体を用いずに直接分散媒を加え
た場合、分散媒は低揮発性であるから、加熱による蒸溜
濃縮は困難で、一定収上の濃度のものは得難い。If a dispersion medium is directly added without using such an intermediate medium, since the dispersion medium has low volatility, it is difficult to distill and concentrate by heating, and it is difficult to obtain a concentration at a constant yield.
また、最初に分散媒の量を少な目に調整して強磁性体微
粒子の含有率を高めようとしても、必ず、分散性があま
り良くない強磁性体微粒子も一緒に一旦溶液中に取り込
まれるため、分散性の良い強磁性体微粒子の含有率は制
限されてしまう。しかも、これら分散性が不十分な強磁
性体微粒子は、遠心分離の際にそれら自身が分離沈降す
るのみならず、隣接して浮遊していた分散性の良い強磁
性体微粒子と一緒に沈降してしまうため、非常に多くの
沈澱物を生じて溶液中の強磁性体微粒子は著しく減少し
、性能上必要な強磁性体微粒子濃度を得ることは困難で
ある。In addition, even if you initially try to increase the content of ferromagnetic particles by adjusting the amount of dispersion medium to a small amount, ferromagnetic particles whose dispersibility is not very good will always be taken into the solution once. The content of ferromagnetic fine particles with good dispersibility is limited. Moreover, these ferromagnetic particles with insufficient dispersibility not only separate and settle themselves during centrifugation, but also settle together with the ferromagnetic particles with good dispersibility that were floating adjacent to them. As a result, a large amount of precipitate is generated and the number of ferromagnetic particles in the solution is significantly reduced, making it difficult to obtain the concentration of ferromagnetic particles required for performance.
もっとも、この発明のフッ素糸系磁性流体組成物を得る
のに、必ずしも上記の中間媒体を介して行う必要はなく
、一般的に行われているように、強磁性体微粒子を直接
に分散媒中に混入させてもよい。However, in order to obtain the fluorine thread-based magnetic fluid composition of the present invention, it is not necessarily necessary to use the above-mentioned intermediate medium. It may be mixed with.
以下に、この発明のフッ素系磁性流体組成物の実施例を
、その製造工程とともに説明する。Examples of the fluorine-based magnetic fluid composition of the present invention will be described below along with the manufacturing process thereof.
〔実施例１〕
まず、硫酸第１鉄と硫酸第２鉄の各１モル／ｌの水溶液
３００−に６ＮのＮ ａ ＯＨ水溶液を加えてｐＨを１
１以上にした後、６０°Ｃで３０分間熟成してマグネタ
イトコロイドを得た。その後、６０°Ｃに保ったままこ
のマグネタイトスラリーに３ＮのＨＣｌを加えてｐＨを
５に調整する。このマグネタイトスラリーに、コロイド
粒子を安定に分散させる界面活性剤として、次の構造式
で示されるパーフルオロポリエーテルカルボン酸（モン
テフルオス社製、ＧＡＲＤＥＮ ｍｏｎｏａｃｔａ）
４０ｇを加え、３０分間撹拌する。[Example 1] First, a 6N NaOH aqueous solution was added to 300 - of 1 mol/l aqueous solutions of ferrous sulfate and ferric sulfate to adjust the pH to 1.
1 or more, and then aged at 60°C for 30 minutes to obtain magnetite colloid. Thereafter, 3N HCl was added to this magnetite slurry while maintaining the temperature at 60°C to adjust the pH to 5. Perfluoropolyether carboxylic acid (manufactured by Montefluos, GARDEN monoacta) represented by the following structural formula was used as a surfactant to stably disperse colloidal particles in this magnetite slurry.
Add 40g and stir for 30 minutes.
Ｆｊ
ＣＦａ ［（ＯＣＦ ＣＦｚ）ｆｉ （ＯＣＦｚ）
ｍ］ ＯＣＦｔ Ｃ０ＯＨ
これを静置し、マグネタイト粒子が凝集し沈降したら、
その上澄を捨てて水を注ぎ、更に水洗する操作を数回繰
り返して、電解質を除去する。水洗が終われば濾過、脱
水する。得られたマグネタイト粒子に沸点９７°Ｃのパ
ーフルオロカーボン（住人スリーエム−社製、ＦＣ−７
７）を低沸点溶媒として加え、十分振盪してマグネタイ
ト粒子を分散させる。これにより、表面を界面活性剤で
被覆した強磁性体微粒子が低沸点溶媒中に分散された中
間媒体が得られる。次にこの中間媒体液を、８０００Ｇ
の遠心力で１時間、遠心分離する。これにより大きなマ
グネタイト粒子を沈降分離せしめた後、その上澄みを取
り出してろ過し、そのろ液をロータリーエバポレータに
採取し、９０°Ｃに保って低沸点パーフルオロカーボン
と水を蒸発させる。蒸発後エバポレータフラスコ内に残
ったマグネタイト粒子を５ｇ取り、これに再び上記の低
沸点パーフルオロカーボンを加えてマグネタイト粒子を
再分散させた後、パーフルオロポリエーテル合成油（Ｍ
ＯＮＴＥＦＬＵＯ３社製、ＦＯＭＢＬＩＮ：ＹＯ６／６
）７ｇを添加しよく混合する。Fj CFa [(OCF CFz)fi (OCFz)
m] OCFt C0OH When this is allowed to stand still and the magnetite particles aggregate and settle,
Discard the supernatant, pour in water, and repeat the process of rinsing with water several times to remove the electrolyte. After washing with water, filter and dehydrate. Perfluorocarbon with a boiling point of 97°C (manufactured by Jujutsu 3M Co., Ltd., FC-7) was added to the obtained magnetite particles.
7) as a low boiling point solvent and shake thoroughly to disperse the magnetite particles. As a result, an intermediate medium is obtained in which fine ferromagnetic particles whose surfaces are coated with a surfactant are dispersed in a low boiling point solvent. Next, this intermediate medium liquid was heated to 8000G
Centrifuge for 1 hour at a centrifugal force of . After large magnetite particles are separated by sedimentation, the supernatant is taken out and filtered, and the filtrate is collected in a rotary evaporator and kept at 90°C to evaporate low-boiling perfluorocarbon and water. After evaporation, take 5 g of magnetite particles remaining in the evaporator flask, add the above low boiling point perfluorocarbon again to redisperse the magnetite particles, and then add perfluoropolyether synthetic oil (M
Manufactured by ONTEFLUO3, FOMBLIN: YO6/6
) and mix well.
この混合物をロータリーエバポレータに採取し、９０°
Ｃに保って低沸点パーフルオロカーボンを蒸発させると
、マグネタイト粒子はパーフルオロポリエーテル合成油
中に分散される゛。これを８０００Ｇの遠心力で３０分
間、遠心分離することにより、非分散固形物は取り除か
れたが、その上部のコロイド溶液は極めて安定な磁性流
体であった。This mixture was collected in a rotary evaporator and
When the low boiling point perfluorocarbon is evaporated while maintaining the temperature at C, the magnetite particles are dispersed in the perfluoropolyether synthetic oil. By centrifuging this at 8000 G centrifugal force for 30 minutes, undispersed solids were removed, but the colloidal solution above was an extremely stable magnetic fluid.
〔実施例２〕
まず、硫酸第１鉄と硫酸第２鉄の各１モル／Ｉｌの水溶
液３００−に６ＮのＮａＯＨ水溶液を加えてｐＨを１１
以上にした後、６０°Ｃで３０分間熟成してマグネタイ
上コロイド水溶液を得た。これを静置し、マグネタイト
粒子が凝集し沈降したら、その上澄を捨てて水を注ぎ、
更に水洗する操作を数回繰り返して、電解質を除去する
。水洗が終われば濾過、脱水し、次いで８０°Ｃで５時
間、真空乾燥した。得られたマグネタイト粒子に、低沸
点のパーフルオロカーボン溶媒（住人スリーエム側社製
、ＦＣ−７７、沸点９７°Ｃ）と、界面活性剤としての
パーフルオロポリエーテルカルボン酸（Ｍ、０ＮＴＥＦ
ＬＵＯ３社製、ＧＡＲＤＥＮ ｍｏｎｏａｃｔｄ）１
６ｇを加え、ボールミルで２時間粉砕混合した。この混
合物をロータリーエバポレータに採取し、９０°Ｃに保
って低沸点パーフルオロカーボンを蒸発せた。蒸発後エ
バポレータフラスコ内に残ったマグネタイト粒子を２ｇ
取り、これに再び上記の低沸点パーフルオロカーボンを
加えてマグネタイト粒子を再分散させた後、パーフルオ
ロポリエーテル合成油（ＭＯＮＴＦ、ＦＬＯＵＳ社製、
ＦＯＭＢＬＩＮ：Ｙ○６／６）２．５ｇを添加しよく混
合する。この混合物をロータリーエバポレータに採取し
、９０°Ｃに保って低沸点パーフルオロカーボン溶媒を
蒸発除去すると、マグネタイト粒子はパーフルオロポリ
エーテル合成油中に分散される。これを８０００Ｇの遠
心力で３０分間、遠心分離することにより、非分散固形
物は取り除かれたが、その上部のコロイド溶液は極めて
安定な磁性流体であった。[Example 2] First, a 6N NaOH aqueous solution was added to 300-1 mol/Il aqueous solution of ferrous sulfate and ferric sulfate to adjust the pH to 11.
After the above-mentioned conditions, the mixture was aged at 60°C for 30 minutes to obtain an aqueous solution of colloid on a magnetite. Leave this to stand, and when the magnetite particles aggregate and settle, discard the supernatant and pour in water.
Further, the electrolyte is removed by repeating the water washing operation several times. After washing with water, it was filtered, dehydrated, and then vacuum-dried at 80°C for 5 hours. The obtained magnetite particles were mixed with a low boiling point perfluorocarbon solvent (manufactured by Jujutsu 3M, FC-77, boiling point 97°C) and perfluoropolyether carboxylic acid (M, 0NTEF) as a surfactant.
Manufactured by LUO3, GARDEN monoactd) 1
6 g was added and mixed by pulverization in a ball mill for 2 hours. This mixture was collected in a rotary evaporator and kept at 90°C to evaporate the low boiling point perfluorocarbon. 2g of magnetite particles remaining in the evaporator flask after evaporation
After adding the above-mentioned low boiling point perfluorocarbon again to redisperse the magnetite particles, perfluoropolyether synthetic oil (MONTF, manufactured by FLOUS Co., Ltd.,
Add 2.5 g of FOMBLIN:Y○6/6) and mix well. This mixture is collected in a rotary evaporator and kept at 90°C to evaporate and remove the low boiling point perfluorocarbon solvent, and the magnetite particles are dispersed in the perfluoropolyether synthetic oil. By centrifuging this at 8000 G centrifugal force for 30 minutes, non-dispersed solids were removed, but the colloidal solution above was an extremely stable magnetic fluid.
この発明によれば、パーフルオロポリエーテル系溶媒中
に、パーフルオロポリエーテル誘導体からなる界面活性
剤を介して、強磁性体微粒子を分散させたため、低蒸気
圧で、潤滑特性も良く、且つ極めて分散安定性にも優れ
たフッ素系磁性流体組成物が得られるという効果がある
。According to this invention, ferromagnetic fine particles are dispersed in a perfluoropolyether solvent via a surfactant made of a perfluoropolyether derivative, resulting in low vapor pressure, good lubricating properties, and extremely This has the effect that a fluorine-based magnetic fluid composition having excellent dispersion stability can be obtained.
またこの発明の製造方法は、表面を界面活性剤で被覆し
た強磁性体微粒子が低沸点パーフルオロ系溶媒中に分散
された中間媒体を介して、分散性の悪い微粒子を選別除
去し、その後、低沸点溶媒は蒸発除去するものとしたた
め、高濃度で且つ極めて安定したフッ素系磁性流体組成
物を容易かつ安価に提供できるという効果がある。In addition, in the production method of the present invention, fine particles with poor dispersibility are selected and removed via an intermediate medium in which ferromagnetic fine particles whose surfaces are coated with a surfactant are dispersed in a low-boiling perfluorinated solvent, and then, Since the low boiling point solvent is removed by evaporation, it is possible to easily and inexpensively provide a highly concentrated and extremely stable fluorine-based magnetic fluid composition.
Claims (16)
面活性剤を介して安定に分散させてなるフッ素系磁性流
体組成物において、前記界面活性剤は一般式 ▲数式、化学式、表等があります▼ （式中のＲは、−ＣＯＯＨ、−ＣＨ＿２ＯＨ、−ＯＨ、
−ＳＯ＿３ＯＨ、−ＰＯ＿３Ｈ、 −ＮＨ＿２などの群から選ばれた極性基 である） で示されるパーフルオロポリエーテル誘導体又はこれら
の塩のうちの少なくとも一種であることを特徴とするフ
ッ素系磁性流体組成物。(1) In a fluorine-based magnetic fluid composition in which ferromagnetic fine particles are stably dispersed in a perfluorinated solvent via a surfactant, the surfactant has a general formula ▲ mathematical formula, chemical formula, table, etc. ▼ (R in the formula is -COOH, -CH_2OH, -OH,
-SO_3OH, -PO_3H, -NH_2, etc.) A fluorinated magnetic fluid composition characterized in that it is at least one of perfluoropolyether derivatives or salts thereof. .
許請求の範囲第１項記載のフッ素系磁性流体組成物。(2) The fluorine-based magnetic fluid composition according to claim 1, wherein the ferromagnetic fine particles have a particle size of 20 to 500 Å.
記パーフルオロ系溶媒中に分散している特許請求の範囲
第１項または第２項記載のフッ素系磁性流体組成物。(3) The fluorinated magnetic fluid composition according to claim 1 or 2, wherein ferromagnetic fine particles are dispersed in the perfluorinated solvent in a volume ratio of 1 to 30%.
） で示されるパーフルオロポリエーテル油である特許請求
の範囲第１項ないし第３項のいずれかに記載のフッ素系
磁性流体組成物。(4) Perfluorinated solvents have general formulas ▲ mathematical formulas, chemical formulas, tables, etc. ▼ (n:m=40:1
) The fluorine-based magnetic fluid composition according to any one of claims 1 to 3, which is a perfluoropolyether oil represented by:
体又はこれらの塩からなる界面活性剤とパーフルオロ系
低沸点溶媒とを加え、表面を前記界面活性剤で被覆した
強磁性体微粒子が低沸点溶媒中に分散された中間媒体を
得る工程と、該中間媒体中の分、散性の悪い微粒子を分
離した後パーフルオロ系溶媒を中間媒体に加えて混合物
とする工程と、該混合物を加熱し前記低沸点溶媒を蒸発
させる工程とを包含するフッ素系磁性流体組成物の製造
方法。(5) A surfactant made of a perfluoropolyether derivative or a salt thereof and a perfluoro-based low boiling point solvent are added to ferromagnetic fine particles, and the ferromagnetic fine particles whose surfaces are coated with the surfactant are used as a low boiling point solvent. a step of obtaining an intermediate medium dispersed in the intermediate medium, a step of adding a perfluoro solvent to the intermediate medium to form a mixture after separating fine particles with poor dispersibility in the intermediate medium, and heating the mixture to form a mixture. and evaporating a low boiling point solvent.
体又はこれらの塩からなる界面活性剤を加えて強磁性体
微粒子の表面を前記界面活性剤で被覆し、該被覆した強
磁性体微粒子にパーフルオロ系低沸点溶媒を加えて中間
媒体を得る特許請求の範囲第５項記載のフッ素系磁性流
体組成物の製造方法。(6) A surfactant made of a perfluoropolyether derivative or a salt thereof is added to the ferromagnetic fine particles to coat the surface of the ferromagnetic fine particles with the surfactant, and the coated ferromagnetic fine particles are coated with perfluorinated fine particles. 6. The method for producing a fluorine-based magnetic fluid composition according to claim 5, wherein an intermediate medium is obtained by adding a low-boiling point solvent.
えて懸濁液とし、該懸濁液にパーフルオロポリエーテル
誘導体又はこれらの塩からなる界面活性剤を加えて中間
媒体を得る特許請求の範囲第５項記載のフッ素系磁性流
体組成物の製造方法。(7) A patent claim for obtaining an intermediate medium by adding a perfluorinated low-boiling point solvent to ferromagnetic fine particles to form a suspension, and adding a surfactant made of a perfluoropolyether derivative or a salt thereof to the suspension. A method for producing a fluorine-based magnetic fluid composition according to item 5.
体又はこれらの塩からなる界面活性剤とパーフルオロ系
低沸点溶媒との混合液を加えて中間媒体を得る特許請求
の範囲第５項記載のフッ素系磁性流体組成物の製造法。(8) Fluorine according to claim 5, in which an intermediate medium is obtained by adding a mixture of a surfactant made of a perfluoropolyether derivative or a salt thereof and a perfluorinated low-boiling solvent to ferromagnetic fine particles. A method for producing a based magnetic fluid composition.
体を生成してから分散性の悪い微粒子を除去し、次いで
該磁性流体を中間媒体に加えて混合物とする特許請求の
範囲第５項記載のフッ素系磁性流体組成物の製造方法。(9) A magnetic fluid is produced using a desired perfluorinated solvent as a dispersion medium, fine particles with poor dispersibility are removed, and the magnetic fluid is then added to an intermediate medium to form a mixture. A method of manufacturing the fluorinated magnetic fluid composition described above.
塩からなる界面活性剤は強磁性体微粒子表面に単分子層
を形成することのできる量だけ添加する特許請求の範囲
第５項ないし第９項の何れかに記載のフッ素系磁性流体
組成物の製造方法。(10) A surfactant consisting of a perfluoropolyether derivative or a salt thereof is added in an amount sufficient to form a monomolecular layer on the surface of the ferromagnetic fine particles. A method for producing a fluorine-based magnetic fluid composition according to claim 1.
導体又はこれらの塩からなる界面活性剤とパーフルオロ
系低沸点溶媒とを加え、表面を前記界面活性剤で被覆し
た強磁性体微粒子が低沸点溶媒中に分散された中間媒体
を得る工程と、該中間媒体中の分散性の悪い微粒子を分
離した後中間媒体を加熱し前記低沸点溶媒を蒸発させる
工程と、該工程を経た強磁性体微粒子にパーフルオロ系
溶媒を加える工程とを包含するフッ素系磁性流体組成物
の製造方法。(11) A surfactant made of a perfluoropolyether derivative or a salt thereof and a perfluoro-based low boiling point solvent are added to ferromagnetic fine particles, and the ferromagnetic fine particles whose surface is coated with the surfactant are used as a low boiling point solvent. a step of separating poorly dispersible fine particles in the intermediate medium and then heating the intermediate medium to evaporate the low boiling point solvent; and adding a perfluorinated solvent.
導体又はこれらの塩からなる界面活性剤を加えて強磁性
体微粒子の表面を前記界面活性剤で被覆し、該被覆した
強磁性体微粒子にパーフルオロ系低沸点溶媒を加えて中
間媒体を得る特許請求の範囲第１１項記載のフッ素系磁
性流体組成物の製造方法。(12) A surfactant made of a perfluoropolyether derivative or a salt thereof is added to the ferromagnetic fine particles to coat the surface of the ferromagnetic fine particles with the surfactant, and the coated ferromagnetic fine particles are coated with perfluoropolyether. 12. The method for producing a fluorine-based magnetic fluid composition according to claim 11, wherein an intermediate medium is obtained by adding a low-boiling point solvent.
加えて懸濁液とし、該懸濁液にパーフルオロポリエーテ
ル誘導体又はこれらの塩からなる界面活性剤を加えて中
間媒体を得る特許請求の範囲第１１項記載のフッ素系磁
性流体組成物の製造方法。(13) A patent claim for obtaining an intermediate medium by adding a perfluorinated low-boiling point solvent to ferromagnetic fine particles to form a suspension, and adding a surfactant made of a perfluoropolyether derivative or a salt thereof to the suspension. A method for producing a fluorine-based magnetic fluid composition according to item 11.
導体又はこれらの塩からなる界面活性剤とパーフルオロ
系低沸点溶媒との混合液を加えて中間媒体を得る特許請
求の範囲第１１項記載のフッ素系磁性流体組成物の製造
法。(14) Fluorine according to claim 11, in which an intermediate medium is obtained by adding a mixture of a surfactant made of a perfluoropolyether derivative or a salt thereof and a perfluorinated low-boiling solvent to ferromagnetic fine particles. A method for producing a based magnetic fluid composition.
流体を生成してから分散性の悪い微粒子を除去し、次い
で該磁性流体を中間媒体に加えて混合物とする特許請求
の範囲第１１項記載のフッ素系磁性流体組成物の製造方
法。(15) Claim 11, in which a magnetic fluid is produced using a desired perfluorinated solvent as a dispersion medium, fine particles with poor dispersibility are removed, and then the magnetic fluid is added to an intermediate medium to form a mixture. A method of manufacturing the fluorinated magnetic fluid composition described above.
塩からなる界面活性剤は強磁性体微粒子表面に単分子層
を形成することのできる量だけ添加する特許請求の範囲
第１１項ないし第１５項の何れかに記載のフッ素系磁性
流体組成物の製造方法。(16) A surfactant consisting of a perfluoropolyether derivative or a salt thereof is added in an amount sufficient to form a monomolecular layer on the surface of the ferromagnetic fine particles. A method for producing a fluorine-based magnetic fluid composition according to claim 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61270594A JPS63124402A (en) | 1986-11-13 | 1986-11-13 | Fluorine-based magnetic fluid composition and manufacture thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61270594A JPS63124402A (en) | 1986-11-13 | 1986-11-13 | Fluorine-based magnetic fluid composition and manufacture thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS63124402A true JPS63124402A (en) | 1988-05-27 |
Family
ID=17488279
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61270594A Pending JPS63124402A (en) | 1986-11-13 | 1986-11-13 | Fluorine-based magnetic fluid composition and manufacture thereof |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63124402A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03139596A (en) * | 1989-10-25 | 1991-06-13 | Nippon Seiko Kk | Magnetic fluid composition, its manufacture, and magnetic fluid sealing device |
| EP0672293A1 (en) * | 1992-10-30 | 1995-09-20 | Lord Corporation | Low viscosity magnetorheological materials |
| US6261471B1 (en) | 1999-10-15 | 2001-07-17 | Shiro Tsuda | Composition and method of making a ferrofluid having an improved chemical stability |
| DE19707027B4 (en) * | 1996-02-22 | 2005-06-02 | Nok Corp. | Fluorine-based magnetic fluid |
| JP2009054958A (en) * | 2007-08-29 | 2009-03-12 | Kagawa Univ | Magnetic fluid, its manufacturing method, magnetic fluid bearing device using the magnetic fluid, and magnetic seal device |
-
1986
- 1986-11-13 JP JP61270594A patent/JPS63124402A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03139596A (en) * | 1989-10-25 | 1991-06-13 | Nippon Seiko Kk | Magnetic fluid composition, its manufacture, and magnetic fluid sealing device |
| EP0672293A1 (en) * | 1992-10-30 | 1995-09-20 | Lord Corporation | Low viscosity magnetorheological materials |
| EP0672293A4 (en) * | 1992-10-30 | 1996-04-17 | Lord Corp | Low viscosity magnetorheological materials. |
| DE19707027B4 (en) * | 1996-02-22 | 2005-06-02 | Nok Corp. | Fluorine-based magnetic fluid |
| US6261471B1 (en) | 1999-10-15 | 2001-07-17 | Shiro Tsuda | Composition and method of making a ferrofluid having an improved chemical stability |
| JP2003524293A (en) * | 1999-10-15 | 2003-08-12 | 株式会社フェローテック | Ferrofluid composition with improved chemical stability and method of manufacture |
| JP4799791B2 (en) * | 1999-10-15 | 2011-10-26 | 株式会社フェローテック | Magnetic fluid composition having improved chemical stability and method of manufacture |
| JP2009054958A (en) * | 2007-08-29 | 2009-03-12 | Kagawa Univ | Magnetic fluid, its manufacturing method, magnetic fluid bearing device using the magnetic fluid, and magnetic seal device |
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