“Blister pack” is a general term that describes packaging that uses a process known as thermoforming. Thermoforming involves heating a sheet of plastic to a temperature where it can be easily formed and molded into any desired shape. The term “blister” refers to the pocket of thermoformed plastic that covers the product.
Blister packs refer to a variety of packaging that have a preformed plastic “pocket” or “shell” (where a product sits securely in place) that is most often heat sealed to an adhesive coated paperboard card or foil backing (think single dose pills or lozenges).
There are many types and variations of blister packs in use in the retail market.
FACE SEAL BLISTER
A flanged blister that surrounds the product and is heat sealed to a piece of paperboard. The seal is only on the flange while the rest of the card stays uncovered.
For heavier products a larger flange or different blister style is generally used.
This is a very common and inexpensive blister pack style if your volumes are high enough (25K – 500K).
FULL FACE SEAL BLISTER
Similar to the face seal, this blister pack’s seal extends to the entire face of the card. This offers more durability and strength to the edges of the card (prevents bent corners) and reinforces the hang hole as well. In addition, it offers a higher perceived value because it looks nicer than the standard face seal blister, but of course is more expensive.
Here is a comparison of a Face Seal Blister vs a Full Face Seal Blister.
While this is technically a full face seal blister, the thermoformed plastic does not extend to the hang tab area.
Tooling costs for the heat seal can be expensive for these face seal blister packs, but a “trapped blister” (see below) doesn’t require heat seal.
TRAPPED BLISTER
This type is similar to the previously mentioned blisters, but instead of heat sealing the blister to the card, it is “trapped” between two cards. The top card is die cut to fit the blister where the product sits. Since trapped blisters do not use heat sealing, no expensive heat seal tooling is required.
The convenient score area in this example provides easy access to the product.
FULL CARD BLISTER
In this configuration, the blister extends to the full size of the card as in the full face seal blister, but instead of being sealed to the card, it has flanges that wrap around the card. The card is simply slid into place and is sometimes secured with a staple.
CLAMSHELL
A clamshell is a container with two halves that are hinged to open and close, just like a clam. It is very strong, robust packaging and excellent for heavy products. Often a blister card is used (but doesn’t have to be) and is inserted, not sealed as in the other styles of blister packs. “Feet” to enable the clamshell to stand upright on store shelves and/or the addition of a hang hole can be easily included in this style of blister. Clamshells can be closed by a snap-shut button or sealed securely with heat, radio frequency or uv light. When sealed in one of these latter three methods, they can be frustrating and even dangerous to open for consumers, but are very tamper resistant as a result. Tooling costs are more expensive for clamshells than the aforementioned blister styles.
MOCK CLAMSHELL
A mock clamshell is a one piece blister where the blister card is sealed to the back of the blister. It is basically quite similar to the full face blister pack except there is a small lip (about a 1/4”) that extends past where the blister card is positioned. This lip is there to enforce the edges and protect the blister card (where all your awesome graphics are printed) from being damaged from potentially rough handling by customers or store workers. Mock clamshells are often half the price of regular clamshells.
2-PIECE CLAMSHELL (Clamshell Variation)
I’ve seen this one a lot in retail stores. It is like a hybrid version of a mock clamshell with an added flat plastic backing that is glued to the blister pocket.
TRI-FOLD CLAMSHELL
Generally used when the product is heavy and unstable if packaged in a regular clamshell, the Tri-Fold Clamshell has two hinges that, when folded, create a wide triangular bottom. This provides a very solid and steady platform for even the most awkward and unbalanced products.
Tri-Fold clamshells are typically more expensive and have higher tooling costs than other types of clamshells.
BLISTER PACK ALTERNATIVES
The following are not technically blister packs and do not use preformed blisters made from sturdy PVC plastic. They instead use plastic films that are more flexible and yet still very durable.
SKIN PACKAGING
This involves a thin film (usually Dupont Surlyn®) that is placed over the product and the paperboard card. Heat and sometimes vacuum is applied in order to adhere the film tightly onto the product and card. This film is very strong and clear and fits the product like an outer “skin”. The product is completely immobilized by the skin which gives added protection to the front of the card as well.
Products with high volumes do well with skin packaging. However, the is a “lesser perceived value” from consumers on products with skin packaging, so a low price point for your product is important.
Skin packaging really behaves like “skin” as it covers the product.
STRETCH PAK (A.K.A STRETCH PACK or STRETCH CARD)
This is very similar to skin packaging except that the backing card is folded and glued to itself. The product is surrounded by a clear plastic film and sits in a die-cut (cutout) area in the paperboard card. The card is then folded in half and sealed onto itself, so the product is essentially sandwiched between the two cards halves. This allows for a complete view of the product while providing plenty of eye-catching marketing real estate on the paperboard card. This packaging is generally designed for the product to stand upright on store shelves or be hung using a standard die-cut hang hole. Or like in Costco stores for example, standing upright in grooves inside tray boxes.
Customers get a full 360˚ view of the product. Stretch Paks can stand on their own on store shelves or be hung using a die-cut hang hole.
Secure seal prevents tampering and product shifting.
The film that secures the product is also very resilient. Notice how the film allows for pressure to be applied without tearing – the film simply “bounces back”
But as you will see here, regular blister packs are not as forgiving.
Skin Packaging and Stretch Pak packaging are more environmentally friendly than blister packs. Costco really loves stretch pak packaging.
I hope this gives you a basic idea of the different types of blister packaging as well as some popular blister alternatives. Please feel free to leave a comment and let me know if everything is clear and understandable or if I’ve missed anything.
This has been a part of my tutorial series called How to Buy Packaging 101. So click the link below to head back if you haven’t finished reading it yet. 🙂
5 Responses
Thanks fro your breakdown very useful.
Is there any differeneation in name for blister packs that have the product that is partly hanging out, as seen in Kitchen Devil knife and screwdriver.
Hi Andrew, no not really, just tell your structural designer you want a hole for your product to come out of. That’s a tactic to save some money on packaging by only covering up the most critical part of the product.
Very informative, thank you
Looking for a Blister package
Hello there – if you are still looking for a blister packaging, try searching by the technical style and or the material you seek if known. Good luck!