JP7394436B2 - Particles for temperature-sensitive magnetic fluid, temperature-sensitive magnetic fluid, method for producing particles for temperature-sensitive magnetic fluid, and method for producing temperature-sensitive magnetic fluid - Google Patents

Particles for temperature-sensitive magnetic fluid, temperature-sensitive magnetic fluid, method for producing particles for temperature-sensitive magnetic fluid, and method for producing temperature-sensitive magnetic fluid Download PDF

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JP7394436B2
JP7394436B2 JP2019115872A JP2019115872A JP7394436B2 JP 7394436 B2 JP7394436 B2 JP 7394436B2 JP 2019115872 A JP2019115872 A JP 2019115872A JP 2019115872 A JP2019115872 A JP 2019115872A JP 7394436 B2 JP7394436 B2 JP 7394436B2
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慶子 石井
耕二 麓
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Chuo University
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Description

本発明は、感温磁性流体用粒子、感温磁性流体、感温磁性流体用粒子の製造方法及び感温磁性流体の製造方法に関する。 The present invention relates to particles for temperature-sensitive magnetic fluids, temperature-sensitive magnetic fluids, methods for producing particles for temperature-sensitive magnetic fluids, and methods for producing temperature-sensitive magnetic fluids.

従来から、強磁性体の微粒子を水、油等の分散媒に分散させた感温磁性流体が知られている。微粒子の粒径は、典型的には１０ｎｍ程度である。感温磁性流体は、温度によって磁化率が変化するため、磁場下で温度差がある場合に自発的に駆動する。従って、外部電源等を用いることなく感温磁性流体を流動させることができ、近年、冷却等を行うデバイスとして注目を集めている。 2. Description of the Related Art Conventionally, temperature-sensitive magnetic fluids in which fine particles of ferromagnetic material are dispersed in a dispersion medium such as water or oil have been known. The particle size of the fine particles is typically about 10 nm. Temperature-sensitive magnetic fluids have magnetic susceptibility that changes depending on temperature, so they are driven spontaneously when there is a temperature difference under a magnetic field. Therefore, it is possible to flow the temperature-sensitive magnetic fluid without using an external power source, and in recent years, it has attracted attention as a device for cooling and the like.

液中の強磁性体の微粒子は、粒子相互が接近すると、磁気吸引力、ファンデルワールス力等の吸引力が作用する。これらの吸引力に抗する斥力を生じさせるため、界面活性剤が使用される（例えば、特許文献１参照）。界面活性剤は、粒子表面に対し不可逆的な吸着性をもつとともに、分散媒となじみのよいものが選定される。特許文献１では、メルカプト基を含有する界面活性剤が、強磁性金属酸化物微粒子の表面に吸着されている。界面活性剤を用いることにより、粒子表面の吸着分子間の立体障害効果が生じ、粒子間の吸引力に抗する斥力を得ることができる。 When fine particles of ferromagnetic material in a liquid come close to each other, attractive forces such as magnetic attractive force and van der Waals force act on them. A surfactant is used to generate a repulsive force that resists these attractive forces (see, for example, Patent Document 1). The surfactant is selected to have irreversible adsorption properties on the particle surface and to be compatible with the dispersion medium. In Patent Document 1, a surfactant containing a mercapto group is adsorbed on the surface of ferromagnetic metal oxide fine particles. By using a surfactant, a steric hindrance effect occurs between adsorbed molecules on the particle surface, and a repulsive force that resists the attraction force between particles can be obtained.

特開２０１８－４１８０７号公報JP 2018-41807 Publication

しかしながら、従来の感温磁性流体では、分散媒に適合した界面活性剤を見出すのは容易ではない。適切な界面活性剤が存在しない場合、その分散媒は用いることができず、使用可能な分散媒が限定されてしまう。 However, in conventional temperature-sensitive magnetic fluids, it is not easy to find a surfactant that is compatible with the dispersion medium. If an appropriate surfactant is not present, the dispersion medium cannot be used, and the dispersion medium that can be used is limited.

また、強磁性材料の微粒子の粒径が小さいため、感温磁性流体に圧力が作用すると粘土状となりやすい。一旦粘土状となった感温磁性流体は微粒子間の吸着力が強く、圧力が解除されても微粒子を再分散させることが困難である。これにより、感温磁性流体が粘土状となって流路に詰まりやすいという問題点もあった。この問題を解決するため、強磁性材料の微粒子の粒径を大きくすることが考えられるが、粒径を大きくすると磁気吸引力が支配的となり、圧力が作用しない状態でも微粒子が凝集して沈殿し、微粒子を分散媒中に的確に分散させることができない。 Furthermore, since the particle size of the fine particles of the ferromagnetic material is small, when pressure is applied to the temperature-sensitive magnetic fluid, it tends to become clay-like. Once the temperature-sensitive magnetic fluid has become clay-like, the adsorption force between particles is strong, and even if the pressure is released, it is difficult to redisperse the particles. As a result, there is a problem in that the temperature-sensitive magnetic fluid becomes clay-like and tends to clog the flow path. In order to solve this problem, it is possible to increase the particle size of the ferromagnetic material particles, but when the particle size is increased, magnetic attraction becomes dominant, and the particles aggregate and precipitate even when no pressure is applied. , the fine particles cannot be accurately dispersed in the dispersion medium.

本発明は、前記事情に鑑みてなされたものであり、その目的とするところは、分散媒の選択自由度を飛躍的に向上させることができ、かつ、流体に圧力が作用した後の再分散性に優れた感温磁性流体用粒子、この感温磁性流体用粒子が分散された感温磁性流体、この感温磁性流体用粒子の製造方法、及び、感温磁性流体の製造方法を提供することにある。 The present invention has been made in view of the above-mentioned circumstances, and its purpose is to dramatically improve the degree of freedom in selecting a dispersion medium, and to improve redispersion after pressure is applied to the fluid. Provided are particles for a temperature-sensitive magnetic fluid with excellent properties, a temperature-sensitive magnetic fluid in which the particles for the temperature-sensitive magnetic fluid are dispersed, a method for producing the particles for the temperature-sensitive magnetic fluid, and a method for producing the temperature-sensitive magnetic fluid. There is a particular thing.

前記目的を達成するため、本発明では、強磁性体からなる複数の感温磁性粒子と、前記複数の感温磁性粒子を内包し非磁性体からなる骨格部と、を有する感温磁性流体用粒子が提供される。 In order to achieve the above object, the present invention provides a temperature-sensitive magnetic fluid comprising a plurality of temperature-sensitive magnetic particles made of a ferromagnetic material and a skeleton part made of a non-magnetic material and containing the plurality of temperature-sensitive magnetic particles. Particles are provided.

この感温磁性流体用粒子によれば、骨格部により感温磁性粒子が内包されているため、感温磁性粒子間に磁気吸引力、ファンデルワールス力等の吸引力が作用してとしても、感温磁性粒子間に介在する骨格部により立体障害効果が生じ、感温磁性粒子間の吸引力に抗する斥力を得ることができる。すなわち、感温磁性流体用粒子が分散される分散媒によらず、常に、感温磁性粒子間の吸引力に抗する斥力を得ることができ、分散媒の選択自由度を飛躍的に向上させることができる。
また、複数の感温磁性粒子が内包されているため、感温磁性流体用粒子の全体の粒径は感温磁性粒子のそれぞれの粒径よりも大きくなる。これにより、感温磁性流体用粒子が分散された感温磁性流体に圧力が作用しても粘土状となり難く、また仮に粘土状となったとしても、感温磁性流体用粒子が大きいために粒子間の吸着力は弱く、圧力解除後の感温磁性流体用粒子の再分散性を向上させることができる。
さらに、各感温磁性粒子は骨格部により覆われるので、各感温磁性粒子を保護することができる。これにより、感温磁性粒子の耐酸化性等が向上する。 According to this temperature-sensitive magnetic fluid particle, since the temperature-sensitive magnetic particles are encapsulated in the skeleton, even if an attractive force such as magnetic attraction force or van der Waals force acts between the temperature-sensitive magnetic particles, The skeleton interposed between the temperature-sensitive magnetic particles causes a steric hindrance effect, and it is possible to obtain a repulsive force that resists the attractive force between the temperature-sensitive magnetic particles. In other words, regardless of the dispersion medium in which the temperature-sensitive magnetic fluid particles are dispersed, it is possible to always obtain a repulsive force that resists the attractive force between the temperature-sensitive magnetic particles, dramatically improving the degree of freedom in selecting the dispersion medium. be able to.
Moreover, since a plurality of temperature-sensitive magnetic particles are included, the overall particle size of the particles for temperature-sensitive magnetic fluid is larger than the particle size of each of the temperature-sensitive magnetic particles. As a result, even if pressure is applied to the temperature-sensitive magnetic fluid in which the temperature-sensitive magnetic fluid particles are dispersed, it is unlikely to become clay-like, and even if it becomes clay-like, the temperature-sensitive magnetic fluid particles are large. The adsorption force between them is weak, and the redispersibility of the temperature-sensitive magnetic fluid particles after the pressure is released can be improved.
Furthermore, since each temperature-sensitive magnetic particle is covered with the skeleton, each temperature-sensitive magnetic particle can be protected. This improves the oxidation resistance of the temperature-sensitive magnetic particles.

上記感温磁性流体用粒子において、前記骨格部は、プラスチックからなっていてもよい。 In the temperature-sensitive magnetic fluid particles described above, the skeleton portion may be made of plastic .

上記感温磁性流体用粒子において、前記骨格部は、内部に複数の気泡を有してもよい。 In the temperature-sensitive magnetic fluid particle described above, the skeleton portion may have a plurality of bubbles inside.

上記感温磁性流体用粒子において、前記骨格部に前記複数の感温磁性粒子とともに内包される潜熱蓄熱材をさらに有してもよい。 The temperature-sensitive magnetic fluid particles may further include a latent heat storage material included in the skeleton together with the plurality of temperature-sensitive magnetic particles.

また、本発明によれば、上記感温磁性流体用粒子と、前記感温磁性流体用粒子が分散された分散媒と、を備えた感温磁性流体が提供される。 Further, according to the present invention, there is provided a temperature-sensitive magnetic fluid comprising the temperature-sensitive magnetic fluid particles and a dispersion medium in which the temperature-sensitive magnetic fluid particles are dispersed.

さらに、本発明によれば、上記感温磁性流体用粒子の製造方法であって、前記骨格部の原料であるポリマーを有機溶媒に溶解させて骨格溶解液を生成する溶解液生成工程と、前記溶解液生成工程にて生成された骨格溶解液に、前記感温磁性粒子を含む感温磁性流体または前記感温磁性粒子を分散させて一次分散液を生成する一次分散工程と、前記一次分散工程にて生成された前記一次分散液を、前記有機溶媒と混和しない外相溶液中に分散させて二次分散液を生成する二次分散工程と、前記二次分散工程にて生成された前記二次分散液から前記有機溶媒を除去し、複数の前記感温磁性粒子が内包された状態で前記骨格部を析出させる骨格部析出工程と、を含む感温磁性流体用粒子の製造方法が提供される。 Further, according to the present invention, there is provided a method for producing particles for a temperature-sensitive magnetic fluid, including a solution generation step of dissolving a polymer, which is a raw material for the skeleton, in an organic solvent to generate a skeleton solution; a primary dispersion step of dispersing the temperature-sensitive magnetic fluid containing the temperature-sensitive magnetic particles or the temperature-sensitive magnetic particles in the skeleton solution generated in the solution generation step to generate a primary dispersion; and the primary dispersion step. a secondary dispersion step of dispersing the primary dispersion produced in the organic solvent in an external phase solution that is immiscible with the organic solvent to produce a secondary dispersion; and There is provided a method for producing particles for a temperature-sensitive magnetic fluid, the method comprising: removing the organic solvent from the dispersion liquid and precipitating the skeleton in a state in which a plurality of the temperature-sensitive magnetic particles are encapsulated. .

さらにまた、本発明によれば、上記感温磁性流体用粒子の製造方法であって、前記骨格部の原料であるポリマーを有機溶媒に溶解させて骨格溶解液を生成する溶解液生成工程と、前記溶解液生成工程にて生成された骨格溶解液に、前記感温磁性粒子を含む感温磁性流体または前記感温磁性粒子を分散させて一次分散液を生成する一次分散工程と、前記一次分散工程にて生成された前記一次分散液を、前記有機溶媒と混和しない外相溶液中に、撹拌により空気が混入した状態で分散させて二次分散液を生成する二次分散工程と、前記二次分散工程にて生成された前記二次分散液から前記有機溶媒を除去し、複数の前記感温磁性粒子及び前記気泡が内包された状態で前記骨格部を析出させる骨格部析出工程と、を含む感温磁性流体用粒子の製造方法が提供される。 Furthermore, according to the present invention, there is provided a method for producing the temperature-sensitive magnetic fluid particles, comprising: dissolving a polymer, which is a raw material for the skeleton, in an organic solvent to generate a skeleton solution; a primary dispersion step of dispersing the temperature-sensitive magnetic fluid containing the temperature-sensitive magnetic particles or the temperature-sensitive magnetic particles in the skeleton solution generated in the solution generation step to generate a primary dispersion; and the primary dispersion. a secondary dispersion step of producing a secondary dispersion by dispersing the primary dispersion produced in the step into an external phase solution that is immiscible with the organic solvent with air mixed therein; a skeleton part precipitation step of removing the organic solvent from the secondary dispersion liquid generated in the dispersion process and precipitating the skeleton part in a state in which a plurality of the temperature-sensitive magnetic particles and the air bubbles are included. A method of making particles for a temperature sensitive magnetic fluid is provided.

上記感温磁性流体用粒子の製造方法において、前記骨格部析出工程にて、前記骨格部析出工程にて、前記二次分散液を所定時間だけ前記有機溶媒の沸点近傍の温度に保持し、前記二次分散液中の前記有機溶媒を前記外相溶液に溶解させて前記外相溶液から揮発させてもよい。 In the method for producing particles for a temperature-sensitive magnetic fluid, the secondary dispersion is maintained at a temperature near the boiling point of the organic solvent for a predetermined period of time in the skeleton precipitation step, and The organic solvent in the secondary dispersion may be dissolved in the external phase solution and volatilized from the external phase solution.

さらにまた、本発明によれば、上記感温磁性流体の製造方法であって、前記骨格部の原料であるポリマーを、前記分散媒と混和しない有機溶媒に溶解させて骨格溶解液を生成する溶解液生成工程と、前記溶解液生成工程にて生成された骨格溶解液に、前記感温磁性粒子を含む感温磁性流体または前記感温磁性粒子を分散させて一次分散液を生成する一次分散工程と、前記一次分散工程にて生成された前記一次分散液を、前記分散媒に分散させて二次分散液を生成する二次分散工程と、前記二次分散工程にて生成された前記二次分散液から前記有機溶媒を除去し、複数の前記感温磁性粒子が内包された状態で前記骨格部を前記分散媒中に析出させる骨格部析出工程と、を含む感温磁性流体の製造方法が提供される。 Furthermore, according to the present invention, there is provided a method for producing the temperature-sensitive magnetic fluid, wherein a polymer as a raw material for the skeleton is dissolved in an organic solvent that is immiscible with the dispersion medium to produce a skeleton solution. liquid generation step, and a primary dispersion step of dispersing the temperature-sensitive magnetic fluid containing the temperature-sensitive magnetic particles or the temperature-sensitive magnetic particles in the skeleton solution generated in the solution generation step to generate a primary dispersion liquid. and a secondary dispersion step of dispersing the primary dispersion produced in the primary dispersion step in the dispersion medium to produce a secondary dispersion, and the secondary dispersion produced in the secondary dispersion step. A method for producing a temperature-sensitive magnetic fluid, comprising: removing the organic solvent from the dispersion liquid, and precipitating the skeleton in the dispersion medium with a plurality of the temperature-sensitive magnetic particles encapsulated therein. provided.

本発明によれば、分散媒の選択自由度が飛躍的に向上し、かつ、流体に圧力が作用した後の感温磁性流体用粒子の再分散性に優れた感温磁性流体を得ることができる。 According to the present invention, the degree of freedom in selecting a dispersion medium is dramatically improved, and it is possible to obtain a temperature-sensitive magnetic fluid with excellent redispersibility of particles for the temperature-sensitive magnetic fluid after pressure is applied to the fluid. can.

本発明の一実施形態を示す感温磁性流体の説明図である。BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram of a temperature-sensitive magnetic fluid showing an embodiment of the present invention. 感温磁性流体用粒子の模式断面説明図である。FIG. 2 is a schematic cross-sectional view of particles for temperature-sensitive magnetic fluid. 感温磁性流体用粒子の製造工程を示すフローチャートである。It is a flowchart which shows the manufacturing process of the particle|grains for temperature-sensitive magnetic fluids. 骨格溶解液に感温磁性粒子を分散させた一次分散液の模式断面説明図である。It is a schematic cross-sectional explanatory view of a primary dispersion liquid in which temperature-sensitive magnetic particles are dispersed in a skeleton solution. 外相溶液に一次分散液を混合させる状態を示す模式断面説明図である。FIG. 2 is a schematic cross-sectional explanatory diagram showing a state in which a primary dispersion liquid is mixed with an external phase solution. 外相溶液に一次分散液を分散させる状態を示す模式断面説明図である。FIG. 2 is a schematic cross-sectional explanatory diagram showing a state in which a primary dispersion liquid is dispersed in an external phase solution. 骨格溶解液中の有機溶媒を除去した状態を示す模式断面説明図である。FIG. 2 is a schematic cross-sectional explanatory diagram showing a state in which the organic solvent in the skeleton solution has been removed. 変形例を示す感温磁性流体用粒子の模式断面説明図である。It is a schematic cross-sectional explanatory view of particles for temperature-sensitive magnetic fluids showing a modified example. 変形例を示す感温磁性流体用粒子の模式断面説明図である。It is a schematic cross-sectional explanatory view of particles for temperature-sensitive magnetic fluids showing a modified example. 実施例と比較例のレオロジー特性を示すグラフであり、（ａ）が実施例を示し、（ｂ）が比較例を示す。It is a graph showing the rheological properties of Examples and Comparative Examples, where (a) shows the Examples and (b) shows the Comparative Examples.

図１から図７は本発明の一実施形態を示すものであり、図１は感温磁性流体の説明図、図２は感温磁性流体用粒子の模式断面説明図、図３は感温磁性流体用粒子の製造工程を示すフローチャート、図４は骨格溶解液に感温磁性粒子を分散させた一次分散液の模式断面説明図、図５は外相溶液に一次分散液を混合させる状態を示す模式断面説明図、図６は外相溶液に一次分散液を分散させる状態を示す模式断面説明図、図７は骨格溶解液中の有機溶媒を除去した状態を示す模式断面説明図である。尚、各図における感温磁性流体用粒子、感温磁性粒子、気泡はあくまで模式的に示したものであり、実際の大きさ、形状等とは異なるものである。 1 to 7 show one embodiment of the present invention, FIG. 1 is an explanatory diagram of a temperature-sensitive magnetic fluid, FIG. 2 is a schematic cross-sectional diagram of particles for a temperature-sensitive magnetic fluid, and FIG. 3 is an explanatory diagram of a temperature-sensitive magnetic fluid. A flowchart showing the manufacturing process of fluid particles, FIG. 4 is a schematic cross-sectional explanatory diagram of a primary dispersion liquid in which temperature-sensitive magnetic particles are dispersed in a skeleton solution, and FIG. 5 is a schematic diagram showing a state in which the primary dispersion liquid is mixed with an external phase solution. FIG. 6 is a schematic cross-sectional view showing a state in which the primary dispersion liquid is dispersed in the external phase solution, and FIG. 7 is a schematic cross-sectional view showing a state in which the organic solvent in the skeleton solution is removed. Incidentally, the temperature-sensitive magnetic fluid particles, temperature-sensitive magnetic particles, and bubbles in each figure are shown only schematically, and are different from the actual size, shape, etc.

図１に示すように、この感温磁性流体用粒子１は、感温磁性を有し、感温磁性流体２の分散媒３中に分散されて利用される。図１は、所定の流路１００に感温磁性流体２が充填されている状態を示している。 As shown in FIG. 1, the temperature-sensitive magnetic fluid particles 1 have temperature-sensitive magnetism and are used by being dispersed in a dispersion medium 3 of the temperature-sensitive magnetic fluid 2. FIG. 1 shows a state in which a predetermined flow path 100 is filled with temperature-sensitive magnetic fluid 2. As shown in FIG.

図２に示すように、感温磁性流体用粒子１は、強磁性体からなる複数の感温磁性粒子１０と、各感温磁性粒子１０を内包し非磁性体からなる骨格部１１と、を有する。すなわち、骨格部１１は、内部に感温磁性粒子１０が収容される空間を複数有している。さらに、本実施形態においては、骨格部１１は、内部に複数の気泡１２を有している。感温磁性流体用粒子１は、球状を呈する。感温磁性流体用粒子１の粒径寸法は任意であるが、流体の仕様等に応じて例えば１μｍ以上１ｍｍ以下の範囲で適宜設定される。 As shown in FIG. 2, the temperature-sensitive magnetic fluid particle 1 includes a plurality of temperature-sensitive magnetic particles 10 made of a ferromagnetic material, and a skeleton part 11 made of a non-magnetic material and containing each temperature-sensitive magnetic particle 10. have That is, the skeleton part 11 has a plurality of spaces in which the temperature-sensitive magnetic particles 10 are accommodated. Furthermore, in this embodiment, the skeleton part 11 has a plurality of air bubbles 12 inside. The temperature-sensitive magnetic fluid particles 1 have a spherical shape. Although the particle size of the temperature-sensitive magnetic fluid particles 1 is arbitrary, it is appropriately set, for example, in the range of 1 μm or more and 1 mm or less depending on the specifications of the fluid.

本実施形態においては、感温磁性粒子１０は金属化合物からなり、骨格部１１はプラスチックからなる。具体的に、感温磁性粒子１０はマグネタイトからなり、骨格部１１はポリ乳酸からなる。また、分散媒３としてエチレングリコール水溶液が用いられる。本実施形態においては、感温磁性粒子１０の粒径は１００ｎｍ程度であり、感温磁性流体用粒子１の粒径は１０μｍ程度である。尚、感温磁性粒子１０は強磁性体であれば材質及び粒径寸法は任意であり、骨格部１１は非磁性体であれば材質及び外径寸法は任意である。また、後述するように、本実施形態の感温磁性流体用粒子１を用いることにより分散媒３の選択自由度が向上しており、分散媒３の材質も任意に変更可能となっている。また、感温磁性粒子１０と感温磁性流体用粒子１の粒径の比率も任意であるが、例えば感温磁性流体用粒子１の粒径を感温磁性粒子１０の粒径の１００倍以上１０００倍以下とすることができる。感温磁性粒子１０としては、マグネタイトの他、フェライト等の他の金属化合物を用いることができる。また、骨格部１１としては、ポリ乳酸の他、ポリ乳酸以外の生分解性プラスチックを用いることができることはもちろん、ポリイソブチルメタクリラート、メタクリル酸メチル、ポリスチレン、ＡＢＳ樹脂、ポリ塩化ビニル等のプラスチックを用いることができる。分散媒３は任意であるが、各種の水系、油系の液体を用いることができ、本実施形態のエチレングリコール水溶液の他、例えば、エチレングリコール、水、各種アルコール、シリコンオイル、アンモニア、アンモニア水溶液、シリコーン油、プロピレングリコール、プロピレングリコール水溶液、フッ素系不活性液体等を用いることができる。また、感温磁性流体用粒子１を、例えばシリコーン材料からなる液体ガスケットのような、比較的粘度の高いペースト状材料に混合させてもよい。 In this embodiment, the temperature-sensitive magnetic particles 10 are made of a metal compound, and the skeleton portion 11 is made of plastic. Specifically, the temperature-sensitive magnetic particles 10 are made of magnetite, and the skeleton portion 11 is made of polylactic acid. Moreover, an ethylene glycol aqueous solution is used as the dispersion medium 3. In this embodiment, the particle size of the temperature-sensitive magnetic particles 10 is about 100 nm, and the particle size of the temperature-sensitive magnetic fluid particles 1 is about 10 μm. The temperature-sensitive magnetic particles 10 may be made of any material and have any particle diameter as long as they are ferromagnetic, and the material and outer diameter of the skeleton portion 11 may be arbitrary as long as they are non-magnetic. Further, as will be described later, by using the temperature-sensitive magnetic fluid particles 1 of this embodiment, the degree of freedom in selecting the dispersion medium 3 is improved, and the material of the dispersion medium 3 can also be changed arbitrarily. Further, the ratio of the particle diameters of the temperature-sensitive magnetic particles 10 and the temperature-sensitive magnetic fluid particles 1 is arbitrary, but for example, the particle size of the temperature-sensitive magnetic fluid particles 1 is 100 times or more the particle size of the temperature-sensitive magnetic particles 10. It can be 1000 times or less. As the temperature-sensitive magnetic particles 10, in addition to magnetite, other metal compounds such as ferrite can be used. In addition to polylactic acid, biodegradable plastics other than polylactic acid can of course be used as the skeleton 11, and plastics such as polyisobutyl methacrylate, methyl methacrylate, polystyrene, ABS resin, and polyvinyl chloride can also be used. Can be used. Although the dispersion medium 3 is arbitrary, various water-based and oil-based liquids can be used, and in addition to the ethylene glycol aqueous solution of this embodiment, for example, ethylene glycol, water, various alcohols, silicone oil, ammonia, and ammonia aqueous solution. , silicone oil, propylene glycol, propylene glycol aqueous solution, fluorine-based inert liquid, etc. can be used. Alternatively, the temperature-sensitive magnetic fluid particles 1 may be mixed into a paste-like material having a relatively high viscosity, such as a liquid gasket made of a silicone material.

本実施形態の感温磁性流体用粒子１は、以下の工程を経て製造される。以下、図３のフローチャートを参照して説明する。
まず、骨格部１１の原料であるポリマーを、有機溶媒に溶解させて骨格溶解液２０を生成する（溶解液生成工程：Ｓ１）。本実施形態においては、ポリ乳酸のポリマーを、有機溶媒としてのジクロロメタンに溶解させる。有機溶媒としては、溶解されるポリマーに応じて適宜選択することができ、ジクロロメタンの他、トルエン、アセトン、シンナー、クロロホルム、酢酸エチル等を用いることができる。 The temperature-sensitive magnetic fluid particles 1 of this embodiment are manufactured through the following steps. The process will be explained below with reference to the flowchart shown in FIG.
First, a polymer, which is a raw material for the skeleton portion 11, is dissolved in an organic solvent to generate a skeleton solution 20 (solution generation step: S1). In this embodiment, a polylactic acid polymer is dissolved in dichloromethane as an organic solvent. The organic solvent can be appropriately selected depending on the polymer to be dissolved, and in addition to dichloromethane, toluene, acetone, thinner, chloroform, ethyl acetate, etc. can be used.

次に、図４に示すように、骨格溶解液２０に感温磁性粒子１０を分散させて一次分散液２１を生成する（一次分散工程：Ｓ２）。そして、この一次分散液２１を、図５に示すように有機溶媒と混和しない外相溶液２２中に混合させた後、図６に示すように撹拌により分散させて二次分散液２３を生成する（二次分散工程：Ｓ３）。本実施形態においては、外相溶液２２としてエチレングリコール水溶液が用いられる。また、本実施形態においては、ホモミキサーによる撹拌により一次分散液２１が分散され、このときの衝撃により一次分散液２１内に空気の気泡１２が混入する。尚、製造される感温磁性流体用粒子１に気泡１２が不要であれば、ホモミキサーによる衝撃力を弱くすることにより、気泡１２の発生を抑制することができる。 Next, as shown in FIG. 4, the temperature-sensitive magnetic particles 10 are dispersed in the skeleton solution 20 to generate a primary dispersion 21 (primary dispersion step: S2). Then, as shown in FIG. 5, this primary dispersion liquid 21 is mixed into an external phase solution 22 that is immiscible with an organic solvent, and then dispersed by stirring as shown in FIG. 6 to produce a secondary dispersion liquid 23 ( Secondary dispersion step: S3). In this embodiment, an ethylene glycol aqueous solution is used as the external phase solution 22. Further, in this embodiment, the primary dispersion liquid 21 is dispersed by stirring with a homomixer, and air bubbles 12 are mixed into the primary dispersion liquid 21 due to the impact at this time. Incidentally, if the air bubbles 12 are not required in the temperature-sensitive magnetic fluid particles 1 to be manufactured, the generation of the air bubbles 12 can be suppressed by weakening the impact force by the homomixer.

この後、二次分散液２３から有機溶媒を除去し、図７に示すように、複数の感温磁性粒子１０及び気泡１２が内包された状態で骨格部１１を析出させる（骨格部析出工程：Ｓ４）。本実施形態においては、二次分散液２３を所定時間だけ有機溶媒の沸点近傍の温度に保持し、一次分散液２１中の有機溶媒を外相溶液２２に溶解させ、外相溶液２２から空気中に揮発させる。このときにも、擾乱の影響により、一次分散液２１内に気泡１２が発生する。尚、製造される感温磁性流体用粒子１に気泡１２が不要であれば、二次分散液２３の温度を有機溶媒の沸点より低くしたり、沸点が比較的高い有機溶媒を用いることにより、気泡１２の発生を抑制することができる。これにより、外相溶液２２中に感温磁性流体用粒子１が生成される。ここで、外相溶液２２として所望の感温磁性流体の分散媒３を選定しておくことで、外相溶液２２に感温磁性流体用粒子１が分散された感温磁性流体２を得ることができる。本実施形態においては、エチレングリコール水溶液に感温磁性流体用粒子１が分散された感温磁性流体２を得ることができる。尚、外相溶液２２を感温磁性流体の分散媒とせずに、外相溶液２２中の感温磁性流体用粒子１を取り出した後に、感温磁性流体用粒子１を所定の分散媒３に分散させてもよいことは勿論である。 After that, the organic solvent is removed from the secondary dispersion liquid 23, and as shown in FIG. 7, the skeleton part 11 is precipitated in a state in which a plurality of temperature-sensitive magnetic particles 10 and air bubbles 12 are included (skeleton part precipitation step: S4). In this embodiment, the secondary dispersion liquid 23 is maintained at a temperature near the boiling point of the organic solvent for a predetermined period of time, the organic solvent in the primary dispersion liquid 21 is dissolved in the external phase solution 22, and the organic solvent is volatilized from the external phase solution 22 into the air. let At this time as well, bubbles 12 are generated within the primary dispersion liquid 21 due to the influence of the disturbance. Incidentally, if the air bubbles 12 are not required in the temperature-sensitive magnetic fluid particles 1 to be produced, by lowering the temperature of the secondary dispersion liquid 23 than the boiling point of the organic solvent, or by using an organic solvent with a relatively high boiling point, Generation of bubbles 12 can be suppressed. As a result, temperature-sensitive magnetic fluid particles 1 are generated in the external phase solution 22. Here, by selecting the desired dispersion medium 3 of the temperature-sensitive magnetic fluid as the external phase solution 22, it is possible to obtain the temperature-sensitive magnetic fluid 2 in which the temperature-sensitive magnetic fluid particles 1 are dispersed in the external phase solution 22. . In this embodiment, it is possible to obtain a temperature-sensitive magnetic fluid 2 in which temperature-sensitive magnetic fluid particles 1 are dispersed in an ethylene glycol aqueous solution. In addition, without using the external phase solution 22 as a dispersion medium for the temperature-sensitive magnetic fluid, after taking out the temperature-sensitive magnetic fluid particles 1 from the external phase solution 22, the temperature-sensitive magnetic fluid particles 1 are dispersed in a predetermined dispersion medium 3. Of course, it is possible.

以上のように構成された感温磁性流体用粒子１によれば、骨格部１１により感温磁性粒子１０が内包されているため、感温磁性粒子１０間に磁気吸引力、ファンデルワールス力等の吸引力が作用してとしても、感温磁性粒子１０間に介在する骨格部１１により立体障害効果が生じ、感温磁性粒子１０間の吸引力に抗する斥力を得ることができる。すなわち、感温磁性流体用粒子１が分散される分散媒３によらず、常に、感温磁性粒子１０間の吸引力に抗する斥力を得ることができ、分散媒３の選択自由度を飛躍的に向上させることができる。 According to the temperature-sensitive magnetic fluid particles 1 configured as described above, since the temperature-sensitive magnetic particles 10 are encapsulated by the skeleton portion 11, magnetic attraction force, van der Waals force, etc. are generated between the temperature-sensitive magnetic particles 10. Even if an attractive force of 2 is applied, a steric hindrance effect occurs due to the skeleton portion 11 interposed between the temperature-sensitive magnetic particles 10, and a repulsive force that resists the attractive force between the temperature-sensitive magnetic particles 10 can be obtained. That is, regardless of the dispersion medium 3 in which the temperature-sensitive magnetic fluid particles 1 are dispersed, it is possible to always obtain a repulsive force that resists the attractive force between the temperature-sensitive magnetic particles 10, greatly increasing the degree of freedom in selecting the dispersion medium 3. can be improved.

従来のように感温磁性粒子を分散媒に直接的に分散させる場合、不凍液や熱伝導率の高い作動流体を分散媒とすると、適切な界面活性剤を選定することが困難であった。しかし、感温磁性粒子１０を骨格部１１に内包させることで凝集を防止することができ、不凍液や熱伝導率の高い作動流体であっても、感温磁性流体用粒子１を分散させることができる。このように、従来は分散媒として使用が困難であった流体に感温磁性流体用粒子１を分散させて感温磁性流体とすることができる。 When temperature-sensitive magnetic particles are directly dispersed in a dispersion medium as in the past, it has been difficult to select an appropriate surfactant when antifreeze or a working fluid with high thermal conductivity is used as the dispersion medium. However, by encapsulating the temperature-sensitive magnetic particles 10 in the skeleton 11, agglomeration can be prevented, and the temperature-sensitive magnetic fluid particles 1 can be dispersed even in antifreeze or a working fluid with high thermal conductivity. can. In this way, the temperature-sensitive magnetic fluid particles 1 can be dispersed in a fluid that has conventionally been difficult to use as a dispersion medium to produce a temperature-sensitive magnetic fluid.

また、複数の感温磁性粒子１０が内包されているため、感温磁性流体用粒子１の全体の粒径は感温磁性粒子１０のそれぞれの粒径よりも大きくなる。これにより、感温磁性流体用粒子１が分散された感温磁性流体２に圧力が作用しても粘土状となり難く、また仮に粘土状となったとしても、感温磁性流体用粒子１が大きいために粒子間の吸着力は弱く、圧力解除後の感温磁性流体用粒子１の再分散性を向上させることができる。 Further, since a plurality of temperature-sensitive magnetic particles 10 are included, the overall particle size of the temperature-sensitive magnetic fluid particles 1 is larger than the particle size of each of the temperature-sensitive magnetic particles 10. As a result, even if pressure is applied to the temperature-sensitive magnetic fluid 2 in which the temperature-sensitive magnetic fluid particles 1 are dispersed, it is unlikely to become clay-like, and even if it becomes clay-like, the temperature-sensitive magnetic fluid particles 1 are large. Therefore, the adsorption force between the particles is weak, and the redispersibility of the temperature-sensitive magnetic fluid particles 1 after the pressure is released can be improved.

さらに、各感温磁性粒子１０は骨格部１１により覆われるので、各感温磁性粒子１０を保護することができる。これにより、感温磁性粒子１０の耐酸化性等が向上する。また、従来、感温磁性粒子は分散媒中で沈殿するために粒径を大きくすることができなかったが、骨格部１１に収容可能な範囲であれば感温磁性粒子１０の粒径を大きくすることができる。例えば、従来、感温磁性粒子は粒径を１５ｎｍ以上とすると分散媒中で沈殿しやすかったが、本実施形態の感温磁性流体用粒子１では、感温磁性粒子１０の粒径を１５ｎｍ以上とすることが可能である。このように、感温磁性粒子１０の粒径を大きくすることにより、感温磁性粒子１０の製造時間を短縮するとともに、感温磁性粒子１０の製造コストの低減を図ることができる。 Furthermore, since each temperature-sensitive magnetic particle 10 is covered with the skeleton part 11, each temperature-sensitive magnetic particle 10 can be protected. This improves the oxidation resistance and the like of the temperature-sensitive magnetic particles 10. In addition, conventionally, the particle size of the temperature-sensitive magnetic particles cannot be increased because they precipitate in the dispersion medium, but the particle size of the temperature-sensitive magnetic particles 10 can be increased within a range that can be accommodated in the skeleton section 11. can do. For example, conventionally, temperature-sensitive magnetic particles tend to precipitate in a dispersion medium when the particle size is 15 nm or more, but in the temperature-sensitive magnetic fluid particles 1 of the present embodiment, the temperature-sensitive magnetic particles 10 have a particle size of 15 nm or more. It is possible to do so. In this way, by increasing the particle size of the temperature-sensitive magnetic particles 10, it is possible to shorten the manufacturing time of the temperature-sensitive magnetic particles 10 and to reduce the manufacturing cost of the temperature-sensitive magnetic particles 10.

また、骨格部１１に気泡１２が含まれているため、分散媒中における感温磁性流体用粒子１の比重を小さくして、分散性及び浮遊性をより高めることができる。さらに、骨格部１１内部の気泡１２の容量を調整して、感温磁性流体用粒子１の比重を調整することができる。 Furthermore, since the skeleton portion 11 contains the air bubbles 12, the specific gravity of the temperature-sensitive magnetic fluid particles 1 in the dispersion medium can be reduced, and the dispersibility and buoyancy can be further improved. Furthermore, the specific gravity of the temperature-sensitive magnetic fluid particles 1 can be adjusted by adjusting the volume of the air bubbles 12 inside the skeleton part 11.

尚、前記実施形態においては、感温磁性粒子１０が直接的に骨格部１１に内包されるものを示したが、例えば図８に示すように、感温磁性粒子１１０を所定の流体に分散させた状態で骨格部１１に内包させることもできる。図８の感温磁性流体用粒子１０１は、強磁性体からなる感温磁性粒子１１０が分散された内部流体１１３と、内部流体１１３を内包し非磁性体からなる骨格部１１と、を有する。すなわち、骨格部１１は、内部に内部流体１１３が収容される空間を複数有している。この変形例においても、骨格部１１は、内部に複数の気泡１２を有している。 In the above embodiment, the temperature-sensitive magnetic particles 10 are directly included in the skeleton 11, but as shown in FIG. 8, the temperature-sensitive magnetic particles 110 may be dispersed in a predetermined fluid. It is also possible to include it in the skeleton part 11 in a state where it is closed. The temperature-sensitive magnetic fluid particles 101 shown in FIG. 8 include an internal fluid 113 in which temperature-sensitive magnetic particles 110 made of ferromagnetic material are dispersed, and a skeleton portion 11 containing the internal fluid 113 and made of a non-magnetic material. That is, the skeleton part 11 has a plurality of spaces in which the internal fluid 113 is accommodated. Also in this modification, the skeleton portion 11 has a plurality of air bubbles 12 inside.

この変形例においては、感温磁性粒子１１０はマグネタイトからなり、内部流体１１３はケロシンからなり、骨格部１１はポリ乳酸からなる。この感温磁性流体用粒子１０１においては、感温磁性粒子１１０の粒径は１０ｎｍ程度であり、内部流体１１３が収容される空間の外径は１００ｎｍ程度であり、感温磁性流体用粒子１０１の粒径は１０μｍ程度である。尚、感温磁性粒子１１０は強磁性体であれば材質及び粒径寸法は任意であり、骨格部１１は非磁性体であれば材質及び外径寸法は任意であり、内部流体１１３の材質及び内部流体１１３が収容される空間の外径も任意である。 In this modification, the temperature-sensitive magnetic particles 110 are made of magnetite, the internal fluid 113 is made of kerosene, and the skeleton portion 11 is made of polylactic acid. In the temperature-sensitive magnetic fluid particles 101, the particle size of the temperature-sensitive magnetic particles 110 is about 10 nm, and the outer diameter of the space in which the internal fluid 113 is accommodated is about 100 nm. The particle size is about 10 μm. Note that the temperature-sensitive magnetic particles 110 can be made of any material and have any particle diameter as long as they are ferromagnetic, the skeleton 11 can be made of any material and have any outer diameter as long as they are non-magnetic, and the material and diameter of the internal fluid 113 can be determined as desired. The outer diameter of the space in which the internal fluid 113 is accommodated is also arbitrary.

この感温磁性流体用粒子１０１は、前記実施形態の一次分散工程にて、内部流体１１３を分散媒として感温磁性粒子１１０が分散された感温磁性流体を骨格溶解液２０に分散して製造することができる。この感温磁性流体用粒子１０１においても、分散媒の選択自由度を飛躍的に向上させることができ、圧力解除後の感温磁性流体用粒子１０１の再分散性を向上させることができる。この変形例では、従来から利用されている粒径の比較的小さな感温磁性粒子１０２が分散された感温磁性流体をそのまま利用して、粒径の比較的大きな感温磁性流体用粒子１０１とすることが可能である。 The temperature-sensitive magnetic fluid particles 101 are manufactured by dispersing the temperature-sensitive magnetic fluid in which the temperature-sensitive magnetic particles 110 are dispersed in the skeleton solution 20 using the internal fluid 113 as a dispersion medium in the primary dispersion process of the embodiment. can do. In this temperature-sensitive magnetic fluid particle 101 as well, the degree of freedom in selecting a dispersion medium can be dramatically improved, and the redispersibility of the temperature-sensitive magnetic fluid particle 101 after pressure release can be improved. In this modification, the conventional temperature-sensitive magnetic fluid in which temperature-sensitive magnetic particles 102 with a relatively small particle size are dispersed is used as is, and the temperature-sensitive magnetic fluid particles 101 with a relatively large particle size are used as is. It is possible to do so.

さらに、例えば図９に示すように、骨格部１１に感温磁性粒子１０以外の材料を含ませることもでき、感温磁性流体用粒子２０１に複数の機能を持たせることが可能である。図９の感温磁性流体用粒子２０１は、複数の感温磁性粒子１０と、複数の潜熱蓄熱材２１４と、各感温磁性粒子１０及び各潜熱蓄熱２１４を内包する骨格部１１と、を有する。潜熱蓄熱材２１４は、所定の融点で固相と液相の間で相変化する。潜熱蓄熱材２１４としては、例えば、パラフィン、シクロヘキサン、ヘキサデカン等を用いることができる。すなわち、骨格部１１は、内部に各感温磁性粒子１０と各潜熱蓄熱材２１４が収容される空間を複数有している。尚、この感温磁性流体用粒子２０１は、骨格部１１の内部に気泡は形成されていない。 Furthermore, as shown in FIG. 9, for example, the skeleton 11 can contain a material other than the temperature-sensitive magnetic particles 10, and the temperature-sensitive magnetic fluid particles 201 can have multiple functions. The temperature-sensitive magnetic fluid particle 201 in FIG. 9 includes a plurality of temperature-sensitive magnetic particles 10, a plurality of latent heat storage materials 214, and a skeleton portion 11 that includes each temperature-sensitive magnetic particle 10 and each latent heat storage 214. . The latent heat storage material 214 undergoes a phase change between a solid phase and a liquid phase at a predetermined melting point. As the latent heat storage material 214, paraffin, cyclohexane, hexadecane, etc. can be used, for example. That is, the skeleton part 11 has a plurality of spaces in which each temperature-sensitive magnetic particle 10 and each latent heat storage material 214 are accommodated. Note that, in the temperature-sensitive magnetic fluid particles 201, no air bubbles are formed inside the skeleton portion 11.

この感温磁性流体用粒子２０１は、前記実施形態の一次分散工程にて、感温磁性粒子１０とともに潜熱蓄熱材２１４を骨格溶解液２０に分散して製造することができる。この感温磁性流体用粒子２０１においても、分散媒の選択自由度を飛躍的に向上させることができ、圧力解除後の感温磁性流体用粒子２０１の再分散性を向上させることができる。これに加え、感温磁性流体用粒子２０１に潜熱蓄熱機能が付与され、感温磁性流体用粒子２０１が分散された感温磁性流体を用いることで蓄熱輸送が可能となる。 The temperature-sensitive magnetic fluid particles 201 can be manufactured by dispersing the latent heat storage material 214 together with the temperature-sensitive magnetic particles 10 in the skeleton solution 20 in the primary dispersion process of the embodiment. In this temperature-sensitive magnetic fluid particle 201 as well, the degree of freedom in selecting a dispersion medium can be dramatically improved, and the redispersibility of the temperature-sensitive magnetic fluid particle 201 after pressure release can be improved. In addition, a latent heat storage function is imparted to the temperature-sensitive magnetic fluid particles 201, and heat storage and transport becomes possible by using the temperature-sensitive magnetic fluid in which the temperature-sensitive magnetic fluid particles 201 are dispersed.

ここで、実際に感温磁性流体用粒子を作製し、これを用いた感温磁性流体と、従来の感温磁性流体のレオロジー特性の比較を行った。レオロジー特性の比較にあたり、実施例の感温磁性流体と比較例の感温磁性流体に含まれる感温磁性粒子について、同じ粒径の感温磁性粒子が同じ量だけ含まれるように調製した。図１０（ａ）は実施例の感温磁性流体のせん断速度とせん断応力のグラフを示し、図１０（ｂ）は比較例の感温磁性流体のせん断速度とせん断応力のグラフを示す。図１０（ａ）及び図１０（ｂ）に示すように、実施例では比較例に対してせん断応力のピーク値が低下し、分散媒中の粒子の分散性が高まっていることが確認された。 Here, particles for a temperature-sensitive magnetic fluid were actually produced, and the rheological properties of a temperature-sensitive magnetic fluid using the particles and a conventional temperature-sensitive magnetic fluid were compared. In comparing the rheological properties, the temperature-sensitive magnetic fluids of the example and the temperature-sensitive magnetic fluid of the comparative example were prepared so that the temperature-sensitive magnetic particles of the same particle size were contained in the same amount. FIG. 10(a) shows a graph of the shear rate and shear stress of the temperature-sensitive magnetic fluid of the example, and FIG. 10(b) shows a graph of the shear rate and shear stress of the temperature-sensitive magnetic fluid of the comparative example. As shown in FIGS. 10(a) and 10(b), it was confirmed that the peak value of shear stress in the example was lower than that of the comparative example, and the dispersibility of particles in the dispersion medium was increased. .

また、微小流路中で実施例の感温磁性流体の流れ場の観察を行ったところ、壁面をこするようにクラスターが移動し、クラスターが揺れながら流れを乱す様子が確認された。このように、通常の流体では壁面の速度がゼロとなるところ、実施例の感温磁性流体では壁面で流速が生じるとともに、擾乱が生じていることが理解される。従って、本発明の感温磁性流体は、熱伝達率が高い冷媒として利用することができる。 Furthermore, when the flow field of the temperature-sensitive magnetic fluid of the example was observed in the microchannel, it was confirmed that the clusters moved as if rubbing against the wall surface, and the clusters swayed and disturbed the flow. In this way, it is understood that while in a normal fluid, the velocity on the wall surface is zero, in the temperature-sensitive magnetic fluid of the example, a flow velocity occurs on the wall surface and disturbance occurs. Therefore, the temperature-sensitive magnetic fluid of the present invention can be used as a refrigerant with a high heat transfer coefficient.

以上、本発明の実施の形態を説明したが、上記に記載した実施の形態は特許請求の範囲に係る発明を限定するものではない。また、実施の形態の中で説明した特徴の組合せの全てが発明の課題を解決するための手段に必須であるとは限らない点に留意すべきである。 Although the embodiments of the present invention have been described above, the embodiments described above do not limit the invention according to the claims. Furthermore, it should be noted that not all combinations of features described in the embodiments are essential for solving the problems of the invention.

１ 感温磁性流体用粒子
２ 感温磁性流体
３ 分散媒
１０ 感温磁性粒子
１１ 骨格部
１２ 気泡
２０ 骨格溶解液
２１ 一次分散液
２２ 外相溶液
２３ 二次分散液
１００ 流路
１０１ 感温磁性流体用粒子
１１０ 感温磁性粒子
１１３ 内部流体
２０１ 感温磁性流体用粒子
２１４ 潜熱蓄熱材 1 Particles for temperature-sensitive magnetic fluid 2 Temperature-sensitive magnetic fluid 3 Dispersion medium 10 Temperature-sensitive magnetic particles 11 Skeletal portion 12 Bubbles 20 Skeletal solution 21 Primary dispersion 22 External phase solution 23 Secondary dispersion 100 Channel 101 For temperature-sensitive magnetic fluid Particles 110 Temperature-sensitive magnetic particles 113 Internal fluid 201 Particles for temperature-sensitive magnetic fluid 214 Latent heat storage material

Claims (9)

強磁性体からなる複数の感温磁性粒子と、
前記複数の感温磁性粒子を内包し非磁性体からなる骨格部と、を有し、
前記骨格部は、複数の潜熱蓄熱材を内包する感温磁性流体用粒子。 A plurality of temperature-sensitive magnetic particles made of ferromagnetic material,
a skeleton part made of a non-magnetic material and containing the plurality of temperature-sensitive magnetic particles ;
The skeleton part is a temperature-sensitive magnetic fluid particle containing a plurality of latent heat storage materials . 前記骨格部は、内部に複数の気泡を有する請求項１に記載の感温磁性流体用粒子。 The particle for temperature-sensitive magnetic fluid according to claim 1 , wherein the skeleton has a plurality of bubbles inside . 前記感温磁性流体用粒子の粒径寸法は、１μｍ以上１ｍｍ以下である請求項２に記載の感温磁性流体用粒子。 The temperature-sensitive magnetic fluid particles according to claim 2, wherein the particle size of the temperature-sensitive magnetic fluid particles is 1 μm or more and 1 mm or less . 前記感温磁性流体用粒子の粒径は、前記感温磁性粒子の粒径の１００倍以上１０００倍以下である請求項３に記載の感温磁性流体用粒子。 4. The temperature-sensitive magnetic fluid particles according to claim 3, wherein the particle size of the temperature-sensitive magnetic fluid particles is 100 times or more and 1000 times or less the particle size of the temperature-sensitive magnetic particles. 請求項１から４のいずれか１項に記載の感温磁性流体用粒子と、
前記感温磁性流体用粒子が分散された分散媒と、を備えた感温磁性流体。 Particles for temperature-sensitive magnetic fluid according to any one of claims 1 to 4,
A temperature-sensitive magnetic fluid comprising: a dispersion medium in which the temperature-sensitive magnetic fluid particles are dispersed. 請求項１に記載の感温磁性流体用粒子の製造方法であって、
前記骨格部は、プラスチックからなり、
前記骨格部の原料であるポリマーを有機溶媒に溶解させて骨格溶解液を生成する溶解液生成工程と、
前記溶解液生成工程にて生成された骨格溶解液に、前記感温磁性粒子を含む感温磁性流体または前記感温磁性粒子を分散させて一次分散液を生成する一次分散工程と、
前記一次分散工程にて生成された前記一次分散液を、前記有機溶媒と混和しない外相溶液中に分散させて二次分散液を生成する二次分散工程と、
前記二次分散工程にて生成された前記二次分散液から前記有機溶媒を除去し、複数の前記感温磁性粒子が内包された状態で前記骨格部を析出させる骨格部析出工程と、を含む感温磁性流体用粒子の製造方法。 A method for producing particles for temperature-sensitive magnetic fluid according to claim 1 , comprising:
The skeleton part is made of plastic,
a solution generation step of dissolving a polymer, which is a raw material for the skeleton, in an organic solvent to generate a skeleton solution;
a primary dispersion step of dispersing the temperature-sensitive magnetic fluid containing the temperature-sensitive magnetic particles or the temperature-sensitive magnetic particles in the skeleton solution generated in the solution generation step to generate a primary dispersion;
a secondary dispersion step in which the primary dispersion produced in the primary dispersion step is dispersed in an external phase solution that is immiscible with the organic solvent to generate a secondary dispersion;
A skeleton part precipitation step of removing the organic solvent from the secondary dispersion liquid generated in the secondary dispersion process and precipitating the skeleton part in a state in which a plurality of the temperature-sensitive magnetic particles are encapsulated. Method for producing particles for temperature-sensitive magnetic fluid. 請求項２に記載の感温磁性流体用粒子の製造方法であって、
前記骨格部は、プラスチックからなり、
前記骨格部の原料であるポリマーを有機溶媒に溶解させて骨格溶解液を生成する溶解液生成工程と、
前記溶解液生成工程にて生成された骨格溶解液に、前記感温磁性粒子を含む感温磁性流体または前記感温磁性粒子を分散させて一次分散液を生成する一次分散工程と、
前記一次分散工程にて生成された前記一次分散液を、前記有機溶媒と混和しない外相溶液中に、撹拌により空気が混入した状態で分散させて二次分散液を生成する二次分散工程と、
前記二次分散工程にて生成された前記二次分散液から前記有機溶媒を除去し、複数の前記感温磁性粒子及び前記気泡が内包された状態で前記骨格部を析出させる骨格部析出工程と、を含む感温磁性流体用粒子の製造方法。 A method for producing particles for temperature-sensitive magnetic fluid according to claim 2 , comprising:
The skeleton part is made of plastic,
a solution generation step of dissolving a polymer, which is a raw material for the skeleton, in an organic solvent to generate a skeleton solution;
a primary dispersion step of dispersing the temperature-sensitive magnetic fluid containing the temperature-sensitive magnetic particles or the temperature-sensitive magnetic particles in the skeleton solution generated in the solution generation step to generate a primary dispersion;
a secondary dispersion step in which the primary dispersion produced in the primary dispersion step is dispersed in an external phase solution that is immiscible with the organic solvent with air mixed therein by stirring to generate a secondary dispersion;
a skeleton part precipitation step in which the organic solvent is removed from the secondary dispersion liquid generated in the secondary dispersion step, and the skeleton part is precipitated in a state in which the plurality of temperature-sensitive magnetic particles and the air bubbles are encapsulated; A method for producing particles for a temperature-sensitive magnetic fluid, comprising: 前記骨格部析出工程にて、前記二次分散液を所定時間だけ前記有機溶媒の沸点近傍の温度に保持し、前記二次分散液中の前記有機溶媒を前記外相溶液に溶解させて前記外相溶液から揮発させる請求項６または７に記載の感温磁性流体用粒子の製造方法。 In the skeleton precipitation step, the secondary dispersion is maintained at a temperature near the boiling point of the organic solvent for a predetermined period of time, and the organic solvent in the secondary dispersion is dissolved in the external phase solution to form the external phase solution. The method for producing particles for a temperature-sensitive magnetic fluid according to claim 6 or 7, wherein the particles are volatilized from a liquid. 請求項５に記載の感温磁性流体の製造方法であって、
前記骨格部は、プラスチックからなり、
前記骨格部の原料であるポリマーを、前記分散媒と混和しない有機溶媒に溶解させて骨格溶解液を生成する溶解液生成工程と、
前記溶解液生成工程にて生成された骨格溶解液に、前記感温磁性粒子を含む感温磁性流体または前記感温磁性粒子を分散させて一次分散液を生成する一次分散工程と、
前記一次分散工程にて生成された前記一次分散液を、前記分散媒に分散させて二次分散液を生成する二次分散工程と、
前記二次分散工程にて生成された前記二次分散液から前記有機溶媒を除去し、複数の前記感温磁性粒子が内包された状態で前記骨格部を前記分散媒中に析出させる骨格部析出工程と、を含む感温磁性流体の製造方法。 A method for producing a temperature-sensitive magnetic fluid according to claim 5, comprising:
The skeleton part is made of plastic,
a solution generation step of producing a skeleton solution by dissolving the polymer, which is a raw material for the skeleton, in an organic solvent that is immiscible with the dispersion medium;
a primary dispersion step of dispersing the temperature-sensitive magnetic fluid containing the temperature-sensitive magnetic particles or the temperature-sensitive magnetic particles in the skeleton solution generated in the solution generation step to generate a primary dispersion;
a secondary dispersion step of dispersing the primary dispersion generated in the primary dispersion step in the dispersion medium to generate a secondary dispersion;
skeletal part precipitation in which the organic solvent is removed from the secondary dispersion liquid produced in the secondary dispersion step, and the skeletal part is precipitated in the dispersion medium with a plurality of the temperature-sensitive magnetic particles encapsulated therein; A method for producing a temperature-sensitive magnetic fluid, comprising:
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