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Blister packs are commonly used as unit-dose packaging for pharmaceutical tablets, capsules etc.  

The primary component of a blister pack is a cavity or pocket made from a formable film, usually a thermoformed plastic or cold formed aluminum film. 

This usually has a lidding seal of aluminum foil. Using different packaging materials and principles of forming, Blister Packs may be divided into three types：aluminum/plastic (thermoforming) blister pack, aluminum/aluminum (cold forming) blister pack and aluminum/plastic/aluminum blister pack.

The advantages of Cold Forming Blister Foil:

The most basic material for the forming web is PVC or Polyvinyl Chloride, for ease of thermoforming and low cost.

The product can be visually examined through the transparent plastic. The fault blister card can be rejected vie the inspecting camera or naked eyes.

Because the cavity or pocket contain the item snugly, it can adopt the universal feeder which consists of circular brushes and planetary agitators that sweep the products into blister pockets. Parts are not required for different formats. This feeder is noted for its low cost and ease of operation.

The use of aluminum offers a nearly complete barrier for moisture，light and oxygen, allowing an extended product expiration date.

The disadvantages of thermoforming blister foil:

The protective properties are not strong because of the PVC’s poor barrier against moisture and oxygen ingress.

The slower speed of production compared to thermoforming;

The package is opaque, making the inspecting system, which rejects the faulty blister card, complicated and costly.

The cost of cold forming aluminum film is higher than PVC.

The larger size of the blister card (aluminum cannot be formed with near 90 degree angles) increases the material cost.

Because the cavity or pocket is larger than the drug, the feeder should be dedicated. this increases the cost and difficulty of operation.

Not suitable for light-sensitive drugs because of the transparency of PVC.