PVDC (polyvinyl chloride/polyvinyl acetate copolymer) coating is usually used in the compounding of pharmaceutical aluminum foil to provide better barrier properties and protection properties. The following is the composite process of general PVDC coating and pharmaceutical aluminum foil:

Prepare the medicinal foil: First, the medicinal foil is cut or trimmed to the required size with the appropriate width and length.

Coated PVDC: During the lamination process, a PVDC coating is applied on one side of the pharmaceutical grade aluminum foil. PVDC coatings can be applied by a variety of methods, the most common of which is through a print coating process.

a. Clean the surface: The surface of pharmaceutical grade aluminum foil needs to be cleaned to ensure good adhesion of the coating. Surfaces are generally cleaned using appropriate cleaners and techniques.
b. Coating PVDC: PVDC solution or dispersion is used in the coating process. The solution or dispersion typically contains solvent, PVDC resin and other additives. The coating process may use a roller, spray or other suitable coating equipment.
c. Drying: After coating, the aluminum foil goes through a drying process to remove solvent or moisture from the coating. The drying method can be by hot air or oven to ensure that the coating can be completely dried.

Lamination: Once the PVDC coating is completely dry, laminate the medicinal aluminum foil with other materials. Often, another layer of packaging material, such as a polymer film, is laminated to one side of the PVDC coating to provide additional functionality and protection.

a. Hot pressing: During the lamination process, the PVDC coating is combined with another layer of packaging material by hot pressing. This method uses heat and pressure to ensure that the two materials are firmly bonded together.
b. Temperature and pressure control: During the hot pressing process, temperature and pressure need to be controlled to ensure that the composite between the PVDC coating and another layer of material is uniform and firm.

Subsequent processing: Once the PVDC coating is compounded with other materials, the composite material can be further processed as required, such as cutting into the required shape and size to meet the requirements of pharmaceutical packaging.

Through the above steps, the PVDC coating can be successfully compounded with pharmaceutical aluminum foil, thus providing excellent barrier properties and protection properties for pharmaceutical packaging.