| 摘要 |
PROBLEM TO BE SOLVED: To provide a freeze drying method of a freeze drying device capable of making nucleus formation of dried material uniformly within a short period of time and without falling a container having dried materials stored when its nucleus formation is made.SOLUTION: At a nucleus forming stage carried out before a preliminary freezing stage, ice particles are formed within a cold trap and this is carried out while being controlled it to a nucleus forming temperature, so that the nucleus formation is rapidly promoted from an upper part to a lower part within the container, large ice crystals are formed, resulting in that moving resistance of water vapor in the existing dried layer is reduced and the primary drying time is shortened. In addition, high blowing air power is not produced when ice particles flow from the cold trap into the dry warehouse, so that the container in the dry warehouse does not fall.SELECTED DRAWING: Figure 1 |
