Capsules are made from pharmaceutical-grade gelatin that meets stringent requirements for use in pharmaceutical products. Capsules are made by forming a thin film of gelatin on a stainless steel mold. The gelatin film then dries and hardens to form a capsule, which is then removed from the mold. There are generally two sizes of molds, one for making the capsule body and the other for making the capsule cap with a larger diameter.

    Due to the characteristics of hollow capsules that are easy to be broken when the water content is too low and easy to soften and deform when too much water, the water content of the hollow capsules should be controlled between 12.5 – 17.5%. It should not be stored under high temperature and high humidity conditions, otherwise it will become sticky and deformed due to heat softening, and it should not be placed in an environment where the temperature is too low or too dry, otherwise, the capsule will easily become brittle and fragile.

    Soft capsules are a special kind of capsules. Since the capsule shells contain a certain amount of glycerin and water, when the storage temperature is too high, the capsule shells will stick together, forming a "clump" between the capsules. Therefore, the general storage conditions of soft capsules are "cool (not more than 20 ℃), dry place".