In the field of pharmaceutical packaging, PVC (polyvinyl chloride) and PVDC (polyvinyl chloride/polyvinyl acetate copolymer) are usually used for lamination with aluminum foil. Both have certain strengths and applicability, but may have different applications in specific situations.

PVC and aluminum foil composite:

Barrier performance: The composite film of PVC and aluminum foil has good oxygen and water vapor barrier performance, which can protect medicines from the influence of moisture and oxygen.
Transparency: PVC and aluminum foil composite film can have a certain degree of transparency, making the medicines in the package visible and easy to observe.

Chemical resistance: PVC and aluminum foil composite film has a certain chemical resistance, which can protect the drug from the influence of the external environment.

Cost-effectiveness: The cost of PVC and aluminum foil lamination is relatively low, which is suitable for some affordable pharmaceutical packaging needs.

PVDC and aluminum foil composite:

High barrier performance: The composite film of PVDC and aluminum foil has excellent oxygen and water vapor barrier performance, which can better protect drugs from oxygen, moisture and other external factors.
High chemical resistance: PVDC and aluminum foil composite film has excellent chemical resistance, which can effectively protect the stability and expiration date of drugs.

Safety: PVDC is generally regarded as a food-grade material with good safety and stability.
Applicable to humidity-sensitive pharmaceuticals: PVDC and aluminum foil composite film has good barrier performance to moisture, and is suitable for humidity-sensitive pharmaceutical packaging.

Therefore, the choice of PVC and aluminum foil composite or PVDC and aluminum foil composite should be comprehensively considered according to the characteristics of specific drugs, packaging requirements, cost factors, and regulatory requirements. In some pharmaceutical packaging that requires high barrier properties and is sensitive to humidity, PVDC and aluminum foil composite films may be more suitable; while in some cases that are more sensitive to cost requirements, PVC and aluminum foil composite films may have more advantages.