Aluminum Blister Packaging
What is Blister Packaging?
Pharmaceutical blister packaging is a process that involves forming hard sheet materials into blister shapes through thermal or cold processing, filling the blisters with medication, and finally heat-sealing a cover material to the blister material, creating a complete medication packaging system.
Blister packaging is one of the main forms of pharmaceutical packaging, widely used for the automated packaging of various dosage forms such as tablets, capsules, granules, suppositories, and inhalation powders.
Pharmaceutical blister packaging is also referred to as bubble eye packaging. Compared to bottle packaging for tablets, blister packaging has significant advantages: it is easy to carry and effectively reduces the risk of contamination during handling and administration.
Composition of Aluminum Blister Packaging
A pharmaceutical blister packaging system generally consists of a lidding material and blister material.
| Material Type | Specific Material | Properties/Description |
| Lidding Material | Aluminum-containing material (PTP aluminum foil) | Inner side coated with ink, equipped with a heat-seal adhesive layer; outer side can be coated with a primer, ink, or protective layer. |
| Pharmaceutical composite aluminum | One side of the aluminum foil is laminated with paper or polyester film, while the other side is coated with ink and a heat-seal adhesive layer. | |
| Blister Material | Single-layer blister material (PVC, PP, PE, PET) | Made from rigid sheet materials, suitable for single-layer blister requirements. |
| Multi-layer blister material | Based on single-layer materials, coated with PVDC or composite films (such as polyethylene, nylon, aluminum foil, etc.). |
Lidding Material
The lidding material can be made of aluminum-containing or plastic materials. When using pharmaceutical aluminum foil, the inner side is coated with ink (if any) and a heat-seal adhesive layer, while the outer side is coated with a primer, ink, or protective layer as needed. This aluminum foil has a tendency to break under pressure, also known as PTP aluminum foil.
Depending on its function, the lidding material may have paper or polyester film laminated on one side of the aluminum foil, and the other side coated with ink (if any) and a heat-seal adhesive layer, referred to as pharmaceutical composite aluminum.
Blister Material
The blister material can be made from plastic or other composite materials.
Single-layer blister materials typically use rigid sheets of polyvinyl chloride (PVC), polypropylene (PP), polyethylene (PE), or polyester (PET).
Multi-layer blister materials usually have coatings of polyvinylidene chloride (PVDC) or composite films such as polyethylene, nylon, aluminum foil, or polychlorotrifluoroethylene (PCTFE) applied to single-layer blister materials.
Characteristics of Aluminum Blister Packaging
- Drug Isolation: Aluminum blisters effectively isolate medications, reducing the risk of cross-contamination while providing excellent protection during transport, ensuring stability and reliability.
- Good Sealing and Shelf Life: After packaging, the sealing and shelf life of the medication are significantly improved, with a maximum storage time of 3 to 5 years.
- Easy to Carry and Use: The compact size of blister packaging makes it easy to carry and administer, enhancing user experience.
- Efficient Production Process: Through advanced production techniques, the entire blister packaging process is completed in one step, shortening production cycles and minimizing disruption to the drug production process, thus maximizing the safety of the medication and its packaging.
Aluminum Blister Packaging Standard Size
| Aluminum Foil Thickness (mm) | 0.025 – 0.028 | 0.02 – 0.023 |
| Tolerance (mm) | +/- 8% of AL foil | |
| Density (GSM/CC) | 2.71 | 2.71 |
| Aluminum Foil Weight (GSM) | 68 | 54 – 67 |
| Aluminum Foil Surface | Matte / Bright | |
| Temper | Hard Temper | |
| Primer (GSM) Max | 1 – 1.5 | |
| Heat Seal Lacquer | 3-5 GSM (Standard) | |
| 6-8 GSM (Special) | ||
Classification of Aluminum Blister Packaging
Blister packaging can be classified based on barrier properties, forming methods, opening methods, and light barrier performance. When designing a pharmaceutical blister packaging system, it is essential to choose the appropriate blister packaging based on the characteristics of the medication.
Classification of Blister Aluminum Packaging by Forming Method
| Forming Method | Material Classification |
| Thermoforming | PVC, PP, PE, PET, COC, PVC/PE, PVC/PVDC, PVC/PVDC/PVC, PVC/PCTFE/PVC, PVCPVDC/PVC, PVC/PCTFE/PVC |
| Cold Stamping | AL/PE, PA/AL/PVC, PA/AL/PE |
| Thermoforming and Cold Stamping | PVC + PA/AL/HSL |
Thermoformed aluminum blister packaging involves heating plastic materials to soften them, followed by shaping them in a mold under pressure.
Cold-stamped aluminum blisters are formed by applying pressure to the material using a stamping die at room temperature.
Classification of Blister Aluminum Packaging by Material
Blister packaging can be primarily categorized into two styles based on the materials used. The commonly seen Alu-PVC packaging and Alu-Alu packaging each have unique characteristics.
Alu-Alu Blister Foil
Alu-Alu blister foil uses aluminum-based materials for both the lid and base of the blister packaging. The aluminum foil layer plays a critical role in protecting the contents inside the blister cavity by effectively blocking moisture, air, and UV light, thereby extending the product's shelf life and enhancing tamper resistance. It is ideal for packaging sensitive medications. Alu-Alu blister foil is typically produced using cold-forming processes, consisting of two layers of aluminum foil sealed together.
In the pharmaceutical industry, Alu-Alu packaging is also referred to as aluminum-aluminum blister packaging. This type of packaging is made using a cold-forming process, consisting of two layers of aluminum foil sealed together. It is an ideal choice for packaging sensitive medications.
Alu-PVC Packaging
Alu-PVC packaging combines plastic blisters with an aluminum foil backing. The transparent PVC film serves as the foundational structure, providing a sturdy and flexible support for the safe storage of medications. The aluminum foil layer is sealed onto the PVC film, creating an effective protective barrier that prevents moisture, oxygen, and light from degrading the medication.
Here's a summary of comparing Alu-Alu Packaging Vs. Blister Packaging. This comparison table will show you a quick overview of the difference between Alu-Alu and blister packaging.
| Alu-Alu Packaging | Alu-PVC Packaging | |
| Composition | Aluminum foil layer sandwiched between plastic film layers | Aluminum foil layer with a layer of polyvinyl chloride (PVC) |
| Barrier Properties | Exceptional shield against humidity, oxygen, and UV rays | Good barrier against moisture and light |
| Visibility | No visibility for the contents inside the blister cavities | Transparent PVC film for excellent product visibility |
| Tamper Resistance | Enhanced tamper resistance with features like blister perforations or tear lines | Can be made tamper-resistant with appropriate blister designs |
| Flexibility | Less flexible, suitable for standard-sized blisters | More flexible, suitable for various blister shapes and sizes |
| Cost | Generally more expensive | Generally more economical |
| Heat Resistance | Aluminum-based materials with good resistance to temperature changes | Plastic-based materials with limited heat resistance |
| Recyclability | Less recyclable due to a combination of materials | More recyclable with separate PVC and aluminum recycling |
| Shelf Life | Extended shelf life due to excellent barrier properties | Good protection but slightly inferior barrier properties |
Classification of Blister Aluminum Packaging by Opening Method and Common Material Structures
Blister packaging typically employs the following four structural methods: push-through, peel-off, peel-and-push, and tear-open.
| Opening Method | Common Material Structures |
| Direct Push-Break | OP/AL/HSL, OP/AL/PVC |
| Peel-Off | Paper/AL/HSL, PET/AL/HSL, Paper/PET/AL/HSL |
| Peel-and-Push | Paper/AL/HSL, PET/AL/HSL, Paper/PET/AL/HSL |
| Packaging Type | Description | Material Composition | Features and Applications |
| Push-Through Blister Packaging | Push-Through Blister Packaging is designed to dispense medication doses by pushing them through the lidding. Typically, hard temper aluminum is used because it has sufficient strength to maintain its integrity without deformation or rupture when the medication is pushed through. Although soft temper aluminum is sometimes used, it is less common due to its lower puncture strength. To enhance child resistance, lidding with higher puncture strength is sometimes chosen. | Hard temper aluminum (commonly used) Soft temper aluminum (less common) | Suitable for packaging that requires high strength and durability. Hard temper aluminum effectively prevents leakage and ensures safety, and is designed to prevent children from opening the packaging. |
| Peel-Open Blister Packaging | Peel-Open Blister Packaging is designed to dispense medication doses by peeling the lidding away from the tray. The lidding typically consists of aluminum combined with paper backing or paper/PET backing. The paper backing adds additional strength and support, while the aluminum provides a protective barrier to prevent environmental factors from affecting the medication. | Aluminum + Paper backing or paper/PET backing | Suitable for packaging designs that are easy for users to open, while effectively protecting the medication from environmental factors. Widely used for pharmaceutical and health product packaging. |
| Peel-Push Blister Packaging | Peel-Push Blister Packaging combines both peeling and pushing actions. The user first peels back one layer of the lidding and then pushes the medication dose through the remaining aluminum foil. The lidding is typically made of a multi-layer material consisting of paper/PET/aluminum foil/HSC. The paper and PET layers provide support and strength, while the aluminum foil ensures protection against moisture, light, and other environmental factors, and the HSC layer strengthens the overall structural integrity. | Paper/PET/Aluminum foil/HSC (high-strength cardboard or similar material) | Suitable for packaging that requires multiple protective layers, effectively preventing moisture or contamination, while being easy to open. Ideal for packaging that requires both peeling and pushing actions. |
| Tear-Open Packaging | Tear-Open Packaging is designed to dispense medication doses by tearing open the package. The materials used typically include a combination of paper/PET/aluminum foil/HSC. The paper layer provides the strength needed for tearing, while the PET and aluminum foil layers offer excellent protective barriers to keep the medication safe from environmental factors. The HSC layer adds durability and support, ensuring that the package remains intact during handling and shipping. | Paper/PET/Aluminum foil/HSC (high-strength cardboard or similar material) | Suitable for simple and easy-to-open packaging designs, allowing for easy tearing while effectively protecting the medication from external factors. Commonly used for pharmaceutical, nutritional products, and other items that need protection from environmental influences. |
Classification of Blister Aluminum Packaging by Light Barrier Performance and Common Material Structures
| Light Barrier Property | Common Material Structures |
| Transparent | PVC, PP, PET, PE, PVC/PE, PVC/PVDC, PVC/PE/PVDC, PVTFE/PVC, PVC/PVDC/PVC |
| Translucent | Colored-PVC, PP, PET, PE |
| Opaque | AL/PE, PA/AL, PVC, PVC + PA/AL/HSL |
Thickness of Popular Pharmaceutical Aluminum Foil Blister Packaging Materials from HC Aluminum
| Aluminum Foil Type | Thickness Range |
| Ultra-Lightweight Aluminum Foil | 0.006 - 0.007 mm |
| Lightweight Aluminum Foil | 0.008 - 0.012 mm |
| Aluminum Strip Packaging Foil | 0.02 - 0.05 mm |
| Aluminum Blister Lid Foil | 0.012 - 0.025 mm |
| Aluminum Cold-Forming Foil | 0.045 - 0.06 mm |
Applications of Aluminum Blister Packaging
Aluminum blister foil is suitable for hard packaging of medical and pharmaceutical products such as pills, capsules, and tablets. The thickness of the aluminum foil typically ranges from 25 to 28 microns. The shiny side is coated with a heat-seal coating, while the matte side is treated with a printed coating.
1. Pharmaceutical Packaging
Pills and Capsules: Aluminum blister foil is commonly used for the unit packaging of pills and capsules, providing good sealing and moisture barrier properties to ensure the stability and efficacy of the medications. Each blister unit can hold one pill or one capsule, facilitating dose control.
Tablets: For various types of tablets, aluminum blister foil effectively prevents oxidation, moisture, and light exposure, ensuring the shelf life of the drugs, especially for those sensitive to environmental factors.
2. Multi-Dose Packaging for Pharmaceutical Products
Blister Packaging: Suitable for medications with multiple doses, typically designed with several blister units in the packaging, allowing patients to take doses as needed. This also reduces the risk of drug exposure, maintaining the quality of the medications.
Unit Design: A well-designed blister layout separates each dose, reducing the risk of cross-contamination and making it easier for patients to identify and use the medication.
The application of aluminum blister foil spans various fields, including pharmaceuticals, health supplements, and clinical trials. Its excellent protective properties, sealing capability, and print adaptability make it the preferred material for pharmaceutical packaging.
Why is Blister Packaging So Popular for Pharmaceuticals?
Below is a summary of reasons why blister packaging is popular for pharmaceuticals, presented in a table format:
| Reason | Detailed Explanation |
| Product Integrity | Medications are sensitive to moisture, oxygen, and light. By selecting suitable blister packaging materials (such as lid foil), an effective barrier can be formed to prevent drug degradation. |
| Protection | Physical damage to the lid is required to access the medication, making it easy to identify potential product or packaging tampering. Additionally, it meets child safety standards, reducing the risk of child poisoning. |
| Customization | The blister packaging tray cavities can be customized, allowing tablets to be securely nested to prevent crushing and damage during transport or handling. |
| Dose Compliance | Each blister unit contains a single dose, making it easy for patients to track medication dosage and accuracy. Pre-printed daily or weekly reminders help patients maintain their medication routine. |
Related Questions
| Question/Information | Detailed Explanation |
| Difference Between Alu Alu and Blister Packaging | Material Composition: Blister packaging typically consists of a plastic base (PVC or PVDC) and an aluminum foil layer; Alu Alu packaging is made from two layers of heat-sealed aluminum foil. |
| Barrier Performance: Alu Alu offers superior barrier performance. | |
| Cost and Production: Alu Alu has a higher production cost. | |
| Thickness of Aluminum Foil for Blister Packaging | Typically ranges from 20 to 30 microns (0.02 to 0.03 mm). |
| Uses of Aluminum Blister Foil | Pharmaceutical Packaging: Used for packaging tablets and capsules, protecting drugs from moisture, oxygen, and light exposure. |
| Nutritional Supplements: Used for packaging vitamins and dietary supplements. | |
| Food Products: Packaging for certain sensitive food items. | |
| Clinical Trials: Used for compliant packaging of pharmaceuticals. |