Blister pack is a term for several types of pre-formed plastic packaging used for small consumer goods, foods, and for pharmaceuticals.

The primary component of a blister pack is a cavity or pocket made from a "formable" web, usually a thermoformed plastic. This usually has a backing of paperboard or a "lidding" seal of aluminum foil or plastic. A blister that folds onto itself is often called a clamshell.

Blister packs for consumer goods basically consist of carded packaging where goods such as toys, hardware, and electrical items are contained between a specially made paperboard card and clear pre-formed plastic such as PVC. The consumer can visually examine the product through the transparent plastic. The plastic shell is vacuum-formed around a mold so it can contain the item snugly. The card is brightly colored and designed depending on the item inside, and the PVC is affixed to the card using heat and pressure to activate an adhesive (heat seal coating) on the blister card. The adhesive is strong enough so that the pack may hang on a peg, but weak enough so so that the package can be easily opened (in theory). Sometimes, with large items, the card has a perforated window for access.

Blister packaging is an inexpensive option for creating packages that are durable, transparent, and tamper proof. These clear plastic blister packs are used in conjunction with a cardboard blister card to keep the product in full view for the customer to examine. The blister packaging is attached to the blister card through a heat-sealing process that allows the product to be displayed in a wide variety of methods. While this heat sealing process can be done with highly automated equipment, the use of blister packs is somewhat limited to light weight items. For heavier items, one should consider using plastic clamshells. Truexpert will work with you to design the blister packaging that works best for your application. We make a variety of shapes and can custom design a blister pack that will showcase your product in the best possible manner

Production:

--In the case of thermoforming, a plastic film or sheet is unwound from the reel and guided though a pre-heating station on the blister line. The temperature of the pre-heating plates (upper and lower plates) is such that the plastic will soften and become pliable. The warm plastic will then arrive in a forming station where a large pressure (4 to 8 bar) will form the blister cavity into a negative mold. The mold is cooled such that the plastic becomes rigid again and maintains its shape when removed from the mold. In case of difficult shapes, the warm film will be physically pushed down partially into the cavity by a "plug-assist" feature. Plug-assist results in a blister cavity with more uniform wall distribution and is typically used when the cavity size and shape is larger than a small tablet.

--In the case of cold forming, an aluminum-based laminate film is simply pressed into a mold by means of a stamp. The aluminum will be elongated and maintain the formed shape. In the industry these blisters are called cold form foil (CFF) blisters. The principal advantage of cold form foil blisters is that the use of aluminum offers a near complete barrier for water and oxygen, allowing an extended product expiry date. The principal disadvantages of cold form foil blisters are: the slower speed of production compared to thermoforming; the lack of transparency of the package (a therapy compliance disadvantage); and the larger size of the blister card (aluminum can not be formed with near 90 degree angles).

Quality: Not all blister packaging is created equally. Although we strive to provide our customers a very competitive price, we will not sacrifice quality to do so. All our blister packagings are tested for clarity, wall thickness, and dimensional compliance before leaving our plant.