Freezing and thawing bag, mold, apparatus and method

(57) The bag (10) used for freeze preservation of a substance unstable with summary heat, its process, and its process are indicated. This bag is characterized by having uniform thickness substantially in length and height. This bag has an end wall (4) which is tinged with the roundness which opens distortion stress, and has a fixed section. An outer edge part encloses the roundish end wall, and it has a suitable acquisition (purchase) portion for a seal, and the bag formed in this way cannot suffer breakage easily, especially when exposed to freeze temperature. In any environmental media of the temperature from which the uniform thickness of the bag differed, the transfer ON of the uniform heat of the content of a bag is brought about. This bag has the space used as efficient storage, two or more bags have the planate big surface, and when it adjoins mutually and is placed, it decreases invasion of the heat to the content of a bag.