The main component of vegetable capsules is medicinal hydroxypropyl methylcellulose (HPMC), namely 2-hydroxypropyl methylcellulose. Cellulose is the most abundant natural polymer in nature. HPMC is usually made from short cotton linter or wood pulp by etherification. As a pharmaceutical excipient, hydroxypropyl methylcellulose is widely used as a binder and coating agent for tablets, and it is safe and reliable to take with many drugs.

    Hydroxylactone is chemically stable, does not react chemically with air and water, and cellulose is metabolically inert, it is not absorbed in the body and is directly excreted. It is not easy to grow microorganisms, so under normal conditions, they will not decompose and deteriorate when placed for a long time.

    Compared with traditional gelatin hollow capsules, vegetable capsules have the advantages of wide adaptability, no risk of cross-linking reaction and high stability, relatively stable drug release speed, small individual differences, not absorbed after disintegration in the human body, and can be excreted with excreted from the body. In terms of storage conditions, after a large number of tests, it is almost not brittle under low humidity conditions, the properties of the capsule are still stable under high humidity conditions, and the various indicators of vegetable capsules are not affected under extreme storage conditions; gelatin capsules are easy to be stored under high humidity conditions. Capsules stick, harden or brittle under low humidity conditions. It is highly dependent on the temperature, humidity and packaging materials of the storage environment.