Blister packs are a common form of packaging used extensively across various industries. This blog post delves into the world of blister packs, exploring their definition, uses, materials, benefits, and types.
A blister pack is a type of pre-formed plastic packaging used for small consumer goods, foods, and pharmaceuticals. It typically consists of a cavity or pocket made from a formable web, usually thermoformed plastic, backed by paperboard or a lidding seal of aluminum foil or plastic.
The history of blister packs is a testament to innovation in packaging technology, especially in the pharmaceutical industry. Initially introduced in the 1960s, blister packs first gained prominence with their use for packaging contraceptive tablets. This novel approach involved molding plastic to securely hold products, a concept that rapidly gained traction due to its effectiveness and versatility.
The success of blister packs with contraceptives marked the beginning of a widespread adoption across various industries. The idea of using a molded plastic cavity to protect and display products proved highly efficient, leading to its rapid expansion beyond pharmaceuticals. Soon, a wide range of items, from consumer goods to medical devices, began to be packaged in blister packs, benefiting from the enhanced protection, visibility, and convenience they offered.
This evolution of blister packs highlights their significant role in transforming packaging solutions, offering a combination of safety, visibility, and tamper-evidence, which has been crucial for industries like pharmaceuticals, consumer electronics, and food products.
Blister packs offer several advantages, making them a popular choice for packaging:
Blister packs, often used for pharmaceutical tablets, capsules, or lozenges, provide unit-dose packaging. They offer barrier protection to extend shelf life and tamper resistance. In Australia, they're primarily used for physician samples or over-the-counter products in pharmacies.
A hinged blister known as a clamshell is used for a variety of products, especially for high-value items like consumer electronics.
These are used for sterile medical devices and are not push-through packs like pharmaceutical blisters.
Blister packs play a crucial role in the medical industry, offering several specific benefits:
The use of blister packs in the medical industry highlights their importance in ensuring the safety, integrity, and compliance of medical products and devices. Blister packs have contributed to reducing intentional overdoses, especially in the context of medications.
Other types of blister packs 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 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 that the package can be easily opened (in theory). Sometimes, with large items, the card (cold seal card) has a perforated window for access.
In this process, a plastic film or sheet is heated, softened, and formed into a blister cavity.
First, a plastic film or sheet is rolled out and warmed up to make it soft and flexible. This warm plastic is then pressed into a mold using high pressure. This mold shapes the plastic into the desired form, like the individual pockets you see in a blister pack. Once the shape is formed, the plastic is cooled down so it becomes firm and keeps its new shape. For more complex shapes, a special technique called "plug-assist" is used, which helps push the plastic into the mold more evenly, ensuring the final product has uniform walls and is well-shaped, especially for larger or more intricate designs.
Cold forming is another method used to make blister packs, but this time with aluminum. Here's how it works: an aluminum-based film is stamped into a mold, shaping it into the desired form, like the pockets you see in a blister pack. This technique is known as cold form foil (CFF) blister packaging. The big benefit of using aluminum is that it's really good at keeping out water and oxygen, which helps products last longer. However, there are some downsides: it's slower to produce than the thermoforming method, you can't see the product inside because aluminum isn't transparent, and the packaging tends to be a bit larger since aluminum doesn't bend at sharp angles very well.
This mix of material is what makes the process of recycling blister packs quite a challenge.
Blister packs are an essential aspect of modern packaging, offering a range of benefits from product protection to consumer safety. Their versatility and efficiency make them a go-to choice in various industries, particularly in pharmaceuticals and consumer goods.
