Blister Packs: Fold-Over &
Two-Part Cards

Blister packs are an important part of the marketing and packaging of consumer goods.

There are three primary types of blister packaging used for consumer goods:

  1. Clear molded polyvinyl chloride (PVC) blister affixed to a simple blister card backing by way of a heat seal coating. These are inexpensive and easy to produce but offer little in the way of security against theft.
  2. Clear molded PVC clamshell with an informational blister card inserted inside. This type of very secure blister pack is an excellent theft deterrent but can be difficult for customers to open.
  3. Blister pack, which Sierra Coating specializes in manufacturing, is a middle ground between single card and clamshell types. A double blister card — either a fold-over or two-part card — with a hole for a blister die cut out of one side. A blister is placed into the hole, the product is placed into the blister, and the backing card is placed over that. The cards are heat sealed together, keeping the blister back in place. This type of blister packaging provides theft-protection while also easing the way for consumers to open the package.

Blister Cards from Sierra Coating

Sierra coats paperboard with water-based heat seal coatings that can be made into fold-over and two-part blister cards. Sierra assists with selecting the right paperboard and heat seal coating to meet a customer’s exact requirements. Our blister card paperboard is a highly versatile addition to blister pack packaging, an already versatile product. Blister card paperboard from Sierra Coating offers a number of benefits for your brand owner customers.

Blister Packaging

Enhanced Protective Features

Switching from molded PVC clamshells to fold-over or two-part blister cards does not have to equate to reduced security for your customers. In fact, our paperboard offers a number of protective features.

When Sierra coats heat seal on paperboard for blister cards, we aim to meet customer specifications for lasting bonds with PVC, polyethylene terephthalate (PET), and other blister pack materials. If your customer’s brand requires additional protections, such as damage from moisture, additional coatings and laminations are also available.

Fold-over and two-part blister packaging is also an excellent theft deterrent; such packaging is an economical way to increase the size of your customers’ product, therefore making it harder to hide during a theft attempt. This is particularly useful for very small but high-value products, such as memory cards.

Furthermore, the nature of heat sealing the blister pack edges between two blister cards secures the blister pack firmly, discouraging in-store opening attempts without overcomplicating the opening process for consumers accessing properly acquired products. Fold-over paperboard can be coated with an anti-tear film to increase its resiliency, and two-part paperboard is available as thick as 32-point, making it naturally tear resistant.

Product Innovations

Two-part and fold-over blister cards are innovative packaging solutions for commercial printers and their brand owner customers. They effectively bridge the gap between the low production cost of single card blister packs and high performance attributes of clamshells, provide excellent surface area on which to display your customers’ marketing and branding imagery, make it easy to package and display uniquely shaped products that do not stand on their own, and provide the strength needed to hang even heavy products.


All blister card paperboard from Sierra Coating can be made recyclable at the customer’s wishes. Switching from clamshell to paper-based blister card not only increases branding capabilities for your customers but also reduces their petroleum-based plastic use for packaging by 50% or more.

Learn More

Fold-over and two-part blister pack backing cards are highly versatile, commonly used for individually packaged consumer products of small size, high value, considerable weight, and unique shape. They are fully customizable, strong, and can be hung for enhanced display.

To learn how blister card paperboard from Sierra Coating can help you best serve your brand owner customers, download our free eBook, “The Financial Case for Contract Manufacturing.” To learn more about our blister packs, or our other product offerings such as heat seal packs or heat seal coated board, contact us today.