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The PVC/OPA/Alum/PVC foil is made of a combination of the thin aluminium layer that is laminated with PVC (polyvinyl chloride) on one side and the other side laminated with OPA (oriented polyamide) and the PVC Layer. It is a multi-structure foil. The foil is the inner and the outer side is the PVC layer. The PVC layer is used as the rigidity of the foil. The PVC layer is the most used plastic, it is easily available and cheap. This foil is used for pharmaceutical blister packaging. The packaging of pharmaceutical finished products like tablets and capsules.
- Total Grammage:
The sample of the PVC/OPA/Alum/PVC foil taken the testing performed total Grammage cut the sample 10 x 10 cm2 area or 5 x 5 cm2 area ( as applicable). Weighing the sample at analytical balance, calculate the total Grammage by the given formula,
Total Grammage = weight in grams x 100 or 400 (if the sample cut 10 x 10 cm2 or 5 x 5 cm2 area)
- PVC layer Grammage:
The total Grammage sample was taken and completely dipped in a glass beaker containing ethyl acetate. After 15-20 min both side PVC layers separated from the OPA/Alum layer. The PVC layer washed the water and dried the sample in a hot air oven for 2 min at 650c. Cool the sample in a desiccator. Weighing the sample of PVC Layer and OPA/Alum foil at analytical balance, calculating the Grammage by the given formula,
Total Grammage = weight in grams x 100 or 400 (if the sample cut 10 x 10 cm2 or 5 x 5 cm2 area)
OPA/Alum Grammage = weight in grams x 100 or 400 (if the sample cut 10 x 10 cm2 or 5 x 5 cm2 area)
- OPA layer Grammage:
The OPA/Alum foil sample was dipped in a glass beaker with a 10 % sodium hydroxide solution. After 15 – 20 min the aluminium layer is dissolved in solution the remaining sample is OPA Layer. Wash the sample in water and dry the sample in a hot air oven for 2 min at 650c. Cool the sample in a desiccator. Weighing the sample at analytical balance, calculating the OPA layer Grammage by the given formula,
OPA layer Grammage = weight in grams x 100 or 400 (if the sample cut 10 x 10 cm2 or 5 x 5 cm2 area)
- Aluminium layer Grammage:
The sample of OPA/Alum Foil Grammage sample and OPA layer Grammage sample calculated the aluminium layer Grammage
Aluminium layer Grammage =weight in grams x 100 or 400 (if the sample cut 10 x 10 cm2 or 5 x 5 cm2 area)