Skip to main content

What is flexible packaging?

Flexible packaging, a term that has become increasingly prevalent in various industries, refers to any package or part of a package whose shape can be readily changed. This includes materials like plastics, films, foils, and papers, often used in combination to leverage their unique properties. The defining characteristic of flexible packaging is its adaptability – it can conform to the product it encases, providing a combination of protection, preservation, and presentation.

Its versatility allows it to be used in a myriad of industries, from food and beverage to pharmaceuticals, cosmetics, and beyond. In the food industry, for instance, flexible packaging plays a crucial role in extending shelf life and maintaining the quality of products. It offers superior protection against environmental factors like moisture, oxygen, and light, which are critical in preserving freshness and preventing spoilage.


In the pharmaceutical sector, flexible packaging ensures the safety and integrity of medications, providing barriers against contamination and facilitating ease of transport and distribution. The cosmetic industry also benefits from flexible packaging, as it allows for innovative and attractive designs that appeal to consumers, while offering the necessary protection for delicate products.

The efficiency and cost-effectiveness of flexible packaging are other vital factors contributing to its widespread adoption. It often results in lower shipping and storage costs due to its lightweight and compact nature. Additionally, the customizable and scalable nature of flexible packaging makes it a preferred choice for businesses looking to adapt quickly to market trends and consumer preferences.

Types of materials used in flexible packaging

  • Plastics: Plastics are arguably the most common material used in flexible packaging. They offer a wide range of properties, including durability, flexibility, and resistance to moisture and chemicals. Common types of plastics used include polyethylene (PE), polypropylene (PP), and polyvinyl chloride (PVC). Each type of plastic offers different characteristics; for example, PE is known for its strength and versatility, while PP is favored for its high melting point, making it suitable for packages that require sterilization.
  • Foils: Aluminum foil is a staple in flexible packaging, especially in the food industry. It’s impermeable to light, oxygen, and moisture, making it an excellent barrier. Foils are often used in combination with other materials to enhance the protective qualities of a package. They are particularly useful in packaging products that are sensitive to light and air, such as certain pharmaceuticals and food items.
  • Films: Films, often made from plastic polymers, are used extensively in flexible packaging for their ability to form thin yet strong barriers. They can be single-layered or multi-layered, combining different materials to enhance protective properties. Biaxially Oriented Polypropylene (BOPP) and Biaxially Oriented Polyethylene Terephthalate (BOPET) are popular choices. These films are known for their clarity, strength, and resistance to external elements.
  • Papers: Paper is a versatile material used in flexible packaging, often coated or laminated with plastics or foils to improve its barrier properties. It is biodegradable and recyclable, making it an environmentally friendly option. Paper is commonly used in packaging where breathability is an important factor, such as in bags for fresh produce or baked goods.

Properties of these materials and their impact on packaging performance

  • Durability and Strength: Materials like plastics and foils offer high durability and strength, protecting products from physical damage during transportation and handling. This is crucial for ensuring the integrity of the product until it reaches the consumer.
  • Barrier Properties: The ability to block moisture, oxygen, light, and other environmental factors is a key property of flexible packaging materials. Foils and multi-layered films provide excellent barriers, which is essential for preserving the quality and extending the shelf life of perishable goods.
  • Flexibility and Lightweight: The inherent flexibility of these materials allows for more efficient use of space in packaging and transportation. Their lightweight nature also contributes to reduced shipping costs and a lower carbon footprint.
  • Chemical Resistance: Plastics and foils offer resistance to chemicals and oils, making them suitable for packaging a wide range of products, including those with acidic or fatty contents.
  • Thermal Properties: Certain materials like PP can withstand high temperatures, making them suitable for packages that require heat in their sealing process or for products that are sterilized after packaging.
  • Sustainability: Paper, being recyclable and biodegradable, offers an eco-friendly packaging option. Innovations in bioplastics and recycling technologies are also enhancing the sustainability of plastic-based flexible packaging.
  • Aesthetics and Printability: The surface of these materials can be easily printed on, allowing for branding and detailed product information. Films and papers offer excellent surfaces for high-quality printing, enhancing the visual appeal of the package.

Key testing methods for flexible packaging

Testing flexible packaging is a crucial procedure employed to determine and validate the suitability of materials and configurations for ensuring the required product safety while optimizing costs.

These examinations encompass:


Tear testing:  this gauges the force needed to tear packaging materials after an incision. This requires a specialized tear tester.


Friction testing: measures the friction coefficient of materials like paper, plastic film, or corrugated cardboard to determine the angle at which the sample begins to slide. A friction tester is used for this measurement.


Thickness testing: this ensures uniform material thickness for all products, a crucial step in guaranteeing the safety of flexible packaging. This test is conducted using a machine equipped with a precise digital micrometer.


Hot tack testing: This evaluates the sealing force of a package to prevent leaks, particularly crucial in medical packaging to preserve sterility. A specific machine called a ‘tack tester’ is utilized for this purpose.


Hot seal testing: This assesses the capabilities of heat sealers, commonly used for sealing flexible packaging, employing specific machines like a hot seal tester to ensure consistent sealing.


Bending stiffness and resistance testing: This is a method to measure material rigidity and elasticity using a dedicated bending resistance tester.

Apart from these tests, flexible packaging may undergo transport simulation tests to prevent potential damages during the distribution cycle to both the package and its contents.

Transport testing machines are highly efficient in simulating the actual conditions a load undergoes during shipping and handling within a laboratory environment. Their primary objective is to facilitate the creation of more effective packaging solutions that protect goods from the distribution hazards.

Additionally, the use of these simulation machines in the process contributes to enhancing the sustainability of packaging designs.

Safe Load Testing Technologies boasts a team of highly experienced engineers specializing in package engineering and the development of innovative transport simulation methods and solutions to optimize and test loads.

innSlide Boomerang Horizontal Acceleration Sled

Programs and tests for flexible packaging: Amazon Frustration-Free Packaging.

The Flexible Ships In Own Container (SIOC) Guidelines, updated in March 2023, are part of Amazon’s efforts to partner with brands globally to reduce brand-supplied packaging and the need for additional protective packaging by Amazon. Here’s a summary of the key points:

To certify items with Amazon, the packaging must undergo a physical performance test to validate that the flexible packaging will be able to withstand Amazon’s distribution chain.

Third-party labs for testing and certifying packaging as SIOC or Frustration-Free Packaging (FFP). Amazon’s Packaging Support and Supplier Network (APASS) provides a list of companies and labs that can assist in testing, designing, and supplying packaging in accordance with Amazon’s guidelines.

flexible packaging

The certification requirements for Amazon’s packaging involve a series of physical performance tests, developed in collaboration with the International Safe Transit Association (ISTA). These tests are designed to ensure that both rigid and flexible packaging can withstand the stresses and rigors of Amazon’s fulfillment network. Here’s a more detailed look at the types of tests and what they entail:


Drop Test:

This is one of the most critical tests. It involves dropping the package from various heights and orientations to simulate the impacts it might experience during handling and transportation. The test assesses the package’s ability to protect its contents and maintain its integrity upon impact.

Learn more about our Drop Testers


Vibration Test:

This test simulates the vibrations a package would experience during transit, whether in trucks, airplanes, or conveyor systems. The goal is to ensure that the packaging and its contents can endure constant shaking and jostling without damage.

Learn more about our Vertical Testing Machines


Compression Test:

The packaging is subjected to weight or pressure that might be experienced during stacking in warehouses or transport vehicles. This test checks the packaging’s strength and durability under sustained pressure.

Learn more about our Compression Testers


Atmospheric Conditioning:

This involves exposing the packaging to various environmental conditions like temperature and humidity changes. The aim is to ensure that the packaging materials can withstand different climatic conditions without degrading or failing.


Incline Impact Test:

This test simulates the horizontal impacts and sudden stops that might occur during transportation. It helps in assessing the package’s ability to withstand collisions with other objects or surfaces.

Learn more about our Impact Testing Machines


Tensile Test:

For flexible packaging, a tensile test might be conducted to measure the strength of the materials used. This test involves stretching the material to its breaking point, which helps in understanding its durability and elasticity.

Safe Load Testing Technologies: Your Ally in Innovation

We are a company dedicated to developing and providing advanced testing equipment and solutions for packaging. Our approach is centered on innovation, creating tools that simulate real-world conditions to ensure packaging integrity and compliance with international standards.

Our product range includes equipment for conducting drop, vibration, compression, and acceleration testing, serving a diverse array of industries. As a company, we focus on delivering data-driven insights and sustainable packaging solutions, aiding businesses in optimizing their packaging designs, reducing environmental impact, and ensuring product safety during transit.

Contact with us today! We’re eager to help you enhance your packaging solutions.