What is blister packaging?

Imagine buying pills, each one individually placed in a small plastic well, sealed on the back with silver aluminum foil. This is the most common blister pack (also called blister pack or aluminum-plastic packaging).

Blister packaging is a unit-dose packaging format . The product is placed in a preformed cavity (the "blister") and sealed with a backing (foil, film, or cardboard) . Blister packaging machines perform the forming , filling , sealing, and cutting steps. Choosing the appropriate blister packaging method , materials, and equipment depends on the product 's characteristics .

The types of blister packaging include aluminum-plastic packaging , aluminum-aluminum packaging, paper-plastic packaging , plastic "clamshell" packaging , and all-plastic blister packaging. Among them, the most common are aluminum -plastic packaging and aluminum-aluminum packaging .

Types of Blister Packaging Machines

1. Aluminum-plastic packaging

Aluminum-plastic packaging is a plastic film blister (such as PVC, PET) formed by heating and mold blistering , and the back sealing material is aluminum foil .

Features : Strike an optimal balance between transparency (easy for visual inspection), barrier properties (moisture and oxygen resistance), and cost . Aluminum foil can be made with a tear line for easy access.

Common applications : most tablets, capsules, soft capsules and other solid oral preparations, health products.

2. Aluminum-aluminum packaging

Aluminum packaging uses aluminum foil on both sides , cold -formed . The bottom aluminum foil (the blister material) is a multi-layer composite aluminum foil . This is formed by cold stamping at room temperature using tremendous mechanical pressure, rather than heat- forming .

Features : Provides top-tier barrier properties , completely shielding against light, oxygen, and moisture . Significantly extends the shelf life of medications. Disadvantages include opacity , preventing direct visibility of the product inside , and high production costs.

Common applications : medicines that are extremely sensitive to moisture and oxygen, such as some highly active APIs, biological products, and highly hygroscopic antibiotics.

3. Paper-plastic packaging

Paper-plastic packaging is a blister formed by blistering plastic film , and the back is a beautifully printed paper card .

Features : Excellent brand display effect , can be printed in color and product descriptions on paper cards. The cost is usually lower and more environmentally friendly.

Common applications : batteries, small electronic products, toys, stationery, hardware tools, cosmetics and other retail accessories .

4. Plastic "clamshell" packaging

Plastic "clamshell" packaging consists of two transparent plastic shells connected by a hinge , which can be opened and closed like a clam shell. They are sealed by ultrasonic welding, snap fasteners or heat seal points.

Features : Strong and durable , providing excellent impact and pressure resistance; excellent visibility , allowing consumers to view the product 360 degrees; strong anti-theft , usually requiring tools to open.

Common applications : consumer electronics (software, SD cards), small electrical accessories, high-end toys, and certain medical devices requiring a sterile barrier.

5. Full plastic blister packaging

The entire package is made entirely of plastic. A deep plastic blister is heat-sealed to a thin, easily tearable plastic film .

Features : Completely transparent , low cost. However, its barrier properties (moisture and oxygen resistance) are usually the worst.

Common applications : non-precision items with low barrier requirements, such as DIY materials (buttons, beads), some candy and food, and low-value hardware parts.

Blister packaging method

Thermoforming (Plastic Blisters):

Plastic film (PVC, PETG, PP) is heated until softened, then a cavity is formed into the plastic using vacuum and/or pressure . Thermoforming produces clear, fast, and cost-effective blisters ideal for tablets, over-the-counter medications, and retail displays.

Cold Forming (Aluminum-Aluminum): An aluminum-based laminate is mechanically pressed into the mold cavity without heating. Cold forming effectively blocks moisture, oxygen, and light , which is crucial for hygroscopic or light-sensitive APIs .

Hot-Cold Hybrid: Some processes combine a clear thermoformed inner layer with a cold-formed outer layer to balance visibility and barrier properties for high-value drugs.

The method you use determines the available materials, machine design, and barrier properties of your packaging – so the choice of method must match your product’s stability needs and marketing requirements.

Working principle of blister packaging machine

The working process of aluminum-plastic blister packaging machine is as follows:

film conveying → heating → blister forming → product filling → film laminating → heat sealing → punching . These processes are completed continuously and at high speed on one machine .

It first heats and softens a roll of flat plastic film, then uses a mold and vacuum to suck out small dimples to form a "blister." Next, the machine accurately fills each blister with tablets or capsules . This is then covered with a layer of aluminum foil . Heat and pressure seal the two materials firmly together . Finally, the machine punches the sealed sheet into small panels, automatically removing scraps. The entire process is continuous, capable of producing hundreds or even more panels per minute. Blister packaging is not only fast but also ensures that each blister is perfectly sealed, guaranteeing product hygiene and shelf life.

Common blister packaging materials

• PVC (rigid) - low cost, high transparency, commonly used for general tablets/capsules.
• PVC + PVDC coating - PVDC provides improved moisture and oxygen resistance while maintaining transparency . Often used when additional protection is needed but visual inspection is still necessary.
• PCTFE / Aclar – High barrier film . Often used when strong barrier properties are required but still require a certain degree of transparency.
• PETG /PET - High transparency and strength, often used in retail clamshell packaging.
• Aluminum foil/aluminum composite sheet - provides top barrier performance for moisture/light-sensitive APIs; used for cold-form packaging.
• Paperboard – Printed backing for retail cards and eco-friendly branding. Film + cover combinations must be stability tested.

How to choose a suitable blister packaging machine

1. First, ask: What product is being packaged?

Product type :

pharmaceutical tablets, capsules, health supplements, medical devices , consumer goods (e.g., batteries, small parts)?

Product Features :

• Are your products sensitive to light, moisture, or oxygen? If they are particularly sensitive, such as certain antibiotics, you might need a cold-form (aluminum-aluminum) packaging machine . This provides top-tier protection. If you have no special requirements , a thermoform (aluminum-plastic) packaging machine will suffice.
• Is a transparent display required? If consumers need to see the product (such as vitamin tablets), a thermoforming machine is a must .
• What is the shape, size and fragility of the product? This determines the design of the forming mold and the filling method, which needs to match the machine precision.

2. What is the production scale? (Output and speed)

Low-speed machines (laboratory/pilot) : Offer lower output (tens of boards per minute) and a simpler structure, making them suitable for R&D, small-batch production, or frequent product formulation changes. They also offer low investment costs.

Medium- and high-speed machines (production type) : High output (hundreds of boards per minute), high degree of automation, stable operation, suitable for large-scale, single-product continuous production. High investment cost.

Key indicator : Evaluate your current and next 3-5 years production needs and select a machine speed (boards/minute) that matches your needs .

3. What regulations and quality requirements must blister packaging machines meet?

Pharmaceutical industry : The machine must comply with GMP (Good Manufacturing Practice) .

Material : Parts in contact with the product must be made of compliant materials such as 316L stainless steel.

Design : The equipment should be easy to clean thoroughly without any unsanitary corners.

Function : Online monitoring functions (such as missing grain detection, batch number printing, and sealing detection) are required to ensure the quality of each plate is controllable.

Consumer goods industry : The requirements are relatively loose, and more attention is paid to production efficiency and cost.

4. What degree of automation does the equipment need?

Manual filling : relies on manual labor to place the product into the blister pit, which is inefficient and prone to errors. It is suitable for extremely low production or experiments.

Automatic Filling : The machine automatically fills the product via a vibrating hopper or robotic vision system . If your product is irregularly shaped or fragile, you should give priority to models with a precision feeding system.

5. How strong is the supplier? (After-sales and support)

Technical support : Can the supplier provide installation, commissioning, operation training and timely troubleshooting?

Spare parts availability : Are common spare parts readily available? What is the supply cycle?

Maintenance service : Is there a localized team of service engineers? How fast is the response?

Case reference : Can you provide successful cases from similar industries in the past?

Quick Selection Guide Sheet

Short Case

If a company is packaging highly hygroscopic antibiotics, aluminum cold-form packaging is recommended because it offers the strongest barrier properties and the best stability. If the product is over-the-counter vitamins, where consumer visibility drives sales, thermoformed PVDC-coated PVC blister packaging is the best option . For retail electronics or batteries, paper-plastic card packaging can create a strong brand image and enhance in-store shelf appeal.

If you need a one-stop blister packaging solution - from material selection, sample testing to design, commissioning and after-sales support . LTPM CHINA can provide you with customized blister packaging solutions for pharmaceuticals and food. We offer mold design, FAT , and a 5- year warranty. Please contact us for a customized solution .

Related topics

1. Barrier properties of blister packaging materials: How to choose?

The core basis for choosing the packaging form . Different materials have different abilities to block oxygen, water vapor (humidity) and light, which directly determines the shelf life of the product.

• High barrier : Cold-formed aluminum foil has the highest barrier properties and can almost completely block water vapor and oxygen.
• Medium barrier : PVC + PVDC coating is a classic combination . PVDC coating improves PVC's ability to resist moisture and oxygen while maintaining transparency.
• Ultra-high barrier transparency : Specialty plastic films such as Aclar® (PCTFE) offer barrier properties close to those of aluminum foil while maintaining complete transparency . However, this is very expensive.
• Basic barrier : Ordinary PVC and PETG are mainly used for products that do not require high barrier properties, such as certain health products or hardware parts.

2. Validation and Regulatory Compliance of Pharmaceutical Blister Packaging

• Equipment Qualification : The machine needs to undergo IQ (Installation Qualification), OQ (Operational Qualification), and PQ (Performance Qualification) in accordance with GAMP5 and other guidelines to prove that it can stably and repeatedly produce products that meet the predetermined quality.
• Packaging process verification : It is necessary to prove that the entire packaging process is under control and can consistently produce well-sealed packages.
• Container seal verification : Various tests (such as color water method, high voltage discharge method, laser head space analyzer) are required to prove the sealing integrity of blister packaging to prevent microbial intrusion.

3. What are the common online detection technologies?

Modern blister packaging machines integrate various inspection systems to ensure 100% quality control.

• Visual inspection system : missing tablets detection (check whether each blister pack is empty), batch number reading (verify whether the printed batch number and expiration date are correct and clear).
• Leak detection : Leak detection (detecting tiny sealing defects through high voltage electricity or laser).
• Weight detection : Weighing after filling to ensure that the weight of the product in each blister pit is within the allowable error range.