BLISTER PACKAGING

General Information About Blister Packaging

In looking at types of retail packaging, blister packs are most affected by pricing because many thermoformers make blister packs, with significant variation in quality.  Most blister packaging utilizes male molds and are typically made from PVC material because of clarity.  Standard gauge, or thickness, is .0075” - .030” with the most common being .010” - .015”.

Design Considerations For Blister Packaging

The primary consideration for the design of blister packs relies within the customer’s need for strength and consistency within the part.  For strength, male parts are stronger at the top of the part for protection, and inconsistent at the flange.  Female blister packs have strength at the flange for consistency and it is important for the bottom of the cavity to have this increased strength.  A consistent flange makes the package easier to seal.

One of the most critical areas of the design process is the trim tolerance.  Plastic Ingenuity requires a +/- 1/32” trim variation because of tooling shifts during the thermoforming process. 

The shape of the part and layout of that shape determine tool spacing.  Because of the changes in shape and layout, material distribution can fluctuate from the middle of the part to the edges.  The overall gauge of the part will be determined through a collaboration of Plastic Ingenuity and the customer. 

It is suggested that the draft of the sidewalls be 10 degrees to aid in the denesting of the part.  Variance from this would be based on a need and would require stacking lugs to aid in the denesting of the parts.

Thermoforming Considerations For Blister Packaging

Material distribution is determined by plugs and process sequence.  Process sequence would be vacuum, form air, tool temperature, and the timing of all of those three.  Undercuts make the parts difficult to remove from the tool, to denest from each other, and to process parts on a heat sealer. 

Plastic Ingenuity uses a "trim in place" blister machine to produce blister packs without undercuts.  This machine allows P.I. to stay competitive within the blister packaging market.

Advantages and Disadvantages For Blister Packaging

Advantages:

• Blister packs are very inexpensive to produce.
• Can be custom fit to help sell/promote products.
• Can have multiple products in a common blister.
• Protects and holds the product securely.
• Many sizes available, from small unit-dose pills to large suit-case sized blisters.
• Allows products to be seen, but not touched.
• Product is very visible.

Disadvantages:

• Blister packaging requires some type of a card to seal the blister to.
• Requires heat sealing the blister pack to the card.