Key Points
- Thermoforming blister packaging is a method that uses heat to create blister packs.
- The cold forming blister packaging technique uses thin sheets of laminate film containing aluminum.
- Thermoforming blister packaging uses transparent PVC material, while cold form blister packaging uses aluminum-based film.
- To create quality blister packs, a cavity or pocket is formed using either aluminum-based foil or clear PVC, depending on the technique you’re using.
- Blister packaging machines typically use a three-step process to manufacture packs.
- Blister machines can work with a variety of forming and lidding materials like PVC, PP, PVDC, COC, aclar, and aluminum-based foil.
Thermoforming Blister Packaging
Thermoforming blister packaging is a method that uses heat to create blister packs. With thermoforming, clear PVC sheets are heated with upper and lower heating plates before being inserted into the packaging machine. Once a sheet enters the machine, it’s soft and pliable, allowing it to shape the selected mold with application pressure. Along with application pressure, a mechanical stamp can also shape the sheet if the mold design is complex.
Cold Form Blister Packaging
The cold forming blister packaging technique uses thin sheets of laminate film containing aluminum. To create blister packs with cold forming, the blister machine typically uses a stamp to force the sheets into a form, allowing the aluminum-based film to stretch and retain the mold shape after the stamp is removed. It’s common to use the cold form blister packaging technique to package pharmaceuticals because aluminum-based film prevents moisture from entering the packaging.
The Difference Between Thermoforming and Cold Forming
There are a few differences between thermoforming and cold forming. Thermoforming blister packaging uses clear PVC material, while cold form blister packaging uses aluminum-based film. The thermoforming blister packaging technique also uses heat, while cold forming doesn’t. The cost to cold form blister packs tends to be higher than thermoforming. Thermoforming blister packaging is also not suitable for light-sensitive drugs due to the clear PVC material.
The Blister Packaging Process
Whether you’re using thermoforming or cold forming, the blister packaging process helps protect your product from moisture, heat, contamination, and UV light. To create quality blister packs, a cavity or pocket is formed using either aluminum-based foil or clear PVC, depending on the technique you’re using. Once the product is inside the cavity, a second layer is added to the seal pack for protection.
Blister packaging machines typically use a three-step process to manufacture packs:
- Forming: A forming mold is used in either the thermoforming or cold forming process to create a tray with cavities or pockets that match specific product requirements.
- Sealing: During the sealing process, your product is placed inside the cavities. Then, the trays are sealed with precut pieces of your choice of lidding material using knurled or flat heat-sealing plates.
- Perforating and Cutting: Finally, the sealed trays are cut and perforated using a precision die cutter.
Selecting Your Blister Packaging Materials
Blister machines can work with a variety of forming and lidding materials, like PVC, PP, PVDC, COC, aclar, and aluminum-based foil.
Forming Materials
Each type of forming material has a different resistance that affects your product’s shelf life and storage condition. Product sensitivity determines the packaging material’s grade level. Highly sensitive products requiring ultimate protection must be packaged using forming materials like aluminum or aclar. Forming film is often colorless and clear, but can be opaque if the product needs light protection.
Lidding Materials
Lidding materials are mostly made from aluminum and have printed primer on one side and coating material made for heat sealing on the other. Heat-sealing lacquer must comply with FDA standards and precisely match the respective forming films, meaning that the predetermined sealing parameter must be guaranteed under any climatic conditions.
Different types of lidding materials are available to meet your product needs, such as hard aluminum for push-through applications, soft aluminum for child-resistant needs, paper aluminum for peel-off applications, and paper PET aluminum for peel-off and child-resistant use.
Choosing Your Machinery
Ascend Packaging Systems offers a wide range of blister packaging machines with thermoforming and cold forming packaging capabilities.
Tabletop Blister Packaging Machines
Our tabletop blister packaging machines are ideal for a variety of products, like tablets, capsules, sachets, pouches, and medical devices. Ascend tabletop machines can be used for either short-run clinical trials or lab-scale packaging operations, and they don’t require toolup or setup.
Semi-Automatic Blister Packaging Machines
Ascend’s semi-automatic blister packaging machines are equipped to handle most medical device packaging and lidding materials, such as PETG, aluminum, and PVC.
Sepha EZ Blister Packaging Machine
The Sepha EZ Blister packaging machine can perform both thermoforming blister packaging and cold forming methods. Available with an optional auto-feed, the EZ Blister also incorporates an auto-feed with a reel holder and a roller-based reel tension system to hold material in place and feed predetermined amounts through the machine for forming or sealing.
Sepha EZ MedPak Blister Machine
Designed for deep-draw products like large tablets and medical devices, the Sepha EZ MedPak Blister machine works on a three-stage operation that handles forming, sealing, perforating, and cutting. The EZ MedPak Blister machine can handle forming materials like PVC, PCTFE laminates, and PETG. Lidding options for the EZ MedPak include peelable aluminum or paper-backed foils and Tyvek.
Providing Blister Packaging Process Solutions
The Ascend team provides a variety of blister packaging process solutions, including high-quality machinery capable of performing either thermoforming blister packaging or cold forming methods. Reach out to us today to learn more about how we can help with your blister packaging needs.
