Blister Packaging in Pharmaceutical Industry

Blister Packaging in Pharmaceutical Industry.

 Blister packaging is widely used in the pharmaceutical industry.

Advantages

  • Unit dose package.
  • It provides excellent environmental protection.
  • Good aesthetic appeal.
  • It offers individual protection until the dose is removed.
  • Lightweight.
  • Easy to dispense and print.
  • No risk of cross-contamination.
  • Cost-effective.
  • No opening or reclosing problems.
  • Tamper evident.

Disadvantages

  • Carton is required as a secondary package.
  • Recycling is not possible.
  • Elderly patients find difficult to tear the packaging system.

Ideal characteristics of blisters are as follows:

  • A backing membrane should be compatible with blister material.
  • It should meet the requirement of child-resistant packaging.
    Should be puncture resistant.
  • It should be sufficient tensile strength.
Blister Packaging


The blister package is formed by heat softening. A sheet of thermoplastic resin and vacuum drawing the softened sheet of plastic into a mold. After cooling, the sheet is released from the mold and proceeds to the filling station of the packaging machine. The semi-rigid blister previously formed is filled with products and lidded with a heat-sealable backing material.

Blister machines utilize the fact that a plastic lm can be softened by heat and then formed in a mould by:
1. Mechanical forming between male and female moulds.
2. Vacuum or negative pressure – which draws the softened lm over or into a mould.
3. Pressure – in which compressed air forces the lm over or into a mould.
4. Combinations of the above.

The backing material or lidding is of type
1. Push through
2. Peelable type
For a push through type of blister, the backing material is usually heat-seal-coated aluminum foil.

Peelable type is having a high degree of puncture resistance to prevent a child from pushing the products through the lidding and must also have sufficient tensile strength to allow the lidding to be pulled away from the blister. It is a type of child-resistant package. For this, a material i.e. polyester or paper is used as a component of backing lamination.
Materials commonly used for the thermoformable blister are PVC/ PE combinations, polystyrene, polypropylene, polyvinylidene chloride.

References

D A Dean, E R Evans, I H Hall “Pharmaceutical Packaging Technology” e-library 2005.