| 摘要 |
PROBLEM TO BE SOLVED: To provide a method and a device for evaluating a sedimentation state, capable of evaluating the sedimentation state inexpensively and with a high precision even if a solid dispersion is sedimented where the specific gravity difference between solid particles and a solvent is small.SOLUTION: In an evaluation device 1, a sedimentation state of solid particles is evaluated on the basis of secular change of the measurement result of viscosity of a specific part. In this case, a solid dispersion which is a measuring object is measured while it is retained to be in a resting state. Even if the solid dispersion is sedimented where the specific gravity difference between the solid particles and a solvent is small, a small viscosity change thereof can be measured and the evaluation accuracy becomes high by performing an accurate viscosity measurement which is not influenced by a flow in the solid dispersion in the above-described manner. As the sedimentation state can be accurately evaluated, it is not necessary to adopt a sedimentation forming method for preparing a constant amount of solid dispersion as a centrifugal separation method or an acceleration test, and even when sedimentation evaluation of an expensive solid dispersion is performed, the cost thereof can be minimized. |
