What is the special function of the metal film for capsules or tablets?

For ordinary capsules, encapsulation with aluminum sheet is mainly considering
Better processing performance (easy to fit plastic materials)
Good sealing performance (aluminum foil can prevent air, water, etc. from entering the capsule packaging)
Good "fragility" (moderate strength, low ductility, easy to take out the capsule)
Mature technology and low cost

For this high-end packaging, additional consideration should be given to:
Protect drugs that are unstable under light conditions
Further insulate air and water from infiltration
Highlight the high-value attributes of drugs