| 摘要 |
PROBLEM TO BE SOLVED: To provide a sublimation refining method capable of increasing yield of a refined sublimate with less amount of a sublimation residue, not only when thermal stability of an object sample of sublimation refining is high but also when thermal stability of the object sample of sublimation refining is low.SOLUTION: Provided is a sublimation refining method using a sublimation refining apparatus having a sublimation pipe, a vacuum pump and piping connecting the sublimation pipe and the vacuum pump. One terminal of the sublimation pipe is closed and to another end thereof is connected the piping linked to the vacuum pump. The object sample of sublimation refining is disposed in a sublimation part placed at a closed terminal side of the sublimation pipe. A space from the sublimation part to a connection part with the piping is defined as a collection part. Pressure in the sublimation pipe during the sublimation refining is maintained to satisfy the following (A) and (B): (A) maximum pressure (Pmax) in the sublimation pipe during the sublimation refining is 50×10Pa or less; and (B) a relationship between the Pmax and pressure (Pend) in the sublimation pipe when sublimation is finished satisfies the following equation (1): [Pmax]/[Pend]≤5 (1). |
