| 摘要 |
PROBLEM TO BE SOLVED: To provide a ferrofluid 1 with low in cost and high in safety, having viscosity characteristics that do not change over a long term even when an environment-friendly material is used, excellent in dispersion stability, and capable of maintaining stable magnetic characteristics.SOLUTION: A ferrofluid 1 is the ferrofluid containing magnetic particles 11 and fine plural oxidized cellulose 12. The fine plural oxidized cellulose 12 are obtained by being oxidized with at least an N-oxyl compound. The number average short axis diameter of short axes of the fine plural oxidized cellulose 12 is 1 nm or more and 200 nm or less, and the number average long axis diameter of long axes of the fine plural oxidized cellulose 12 is 0.05 μm or more and 50 μm or less.SELECTED DRAWING: Figure 1 |
