Understanding Barrier Properties in Flexible Packaging

Protecting the product is arguably the most essential aspect of a brand’s packaging considerations. As such, it is one of the key reasons so many brands choose stand-up pouches for their products today. Thanks to high-barrier films, stand-up pouches easily defend against moisture, oxygen, odours and light (the main culprits behind spoilage and reduced shelf life). 

Thanks to high-barrier films, modern packaging can keep food, supplements, and other products fresh longer without relying on bulky containers or added preservatives. For e-commerce brands especially, that kind of shelf-life extension can be huge. It allows for more efficient inventory management, less waste, and better protection during transit.

How Barrier Properties Work

Flexible packaging achieves this level of protection through multi-layered films, with each layer contributing a specific barrier function. The result is a strong, lightweight, and protective solution.

Two key measurements help define how well a packaging film performs:

• WVTR (Water Vapour Transmission Rate):
  Measures how much water vapour passes through the packaging (film) over time. A lower WVTR (sometimes referred to as Moisture Vapour Transmission Rate MVTR) means stronger resistance to moisture and a better moisture barrier overall.
• OTR (Oxygen Transmission Rate):
  Measures the amount of oxygen that permeates through the film. A lower OTR means better protection against oxidation, which is critical for many food and pharmaceutical products like coffee, snacks.

Pro Tip: The lower the WVTR and OTR, the better the barrier.

Other barrier properties to consider are light/UV barriers, aroma or gas barriers, grease/oil resistance. 

Matching the Barrier to the Product

No two products are the same and neither are their packaging needs. The effectiveness of a barrier depends on several variables:

• The type and thickness of the film
• The sensitivity of the product to moisture, oxygen, or light
• The desired shelf life
• Storage and shipping conditions like temperature and humidity

For instance, packaging a dry snack in a humid environment? You'll want ultra-low WVTR films. Selling coffee or supplements with active ingredients? Low OTR is a must to preserve quality and potency. Cannabis? Packaging must provide ultra-low oxygen and moisture transmission rates, odour control, and UV resistance to protect sensitive cannabinoids and terpenes, preserve potency and flavour, and prevent aroma leakage.

Materials that Deliver High Barrier Protection

Flexible packaging can be made from various materials with built-in or applied barriers. Choices can include: 

• PET, PE and PP films
• EVOH (for oxygen resistance)
• Aluminum foil
• Metalized films
• PLA (polylactic acid), a biodegradable film with specialty coatings (for compostable options)

At Associated, we offer multi-layer film laminations that combine the strengths of different materials to achieve optimal performance.

Barrier Properties and Sustainability: Can you Have Both?

Absolutely! But, it takes the right design. High-barrier packaging doesn’t have to mean hard-to-recycle laminates. At Associated, we work with clients to balance performance and environmental responsibility using the latest innovations to create the perfect blend of high functioning and sustainable packaging products.

When it comes to packaging, the right solution can mean the difference between a product that spoils and one that sells. Barrier properties in flexible packaging can make all the difference. At Associated Labels and Packaging, we help brands design packaging that looks great and works even better. Want to know if your current solution is delivering the protection your product needs? Let’s talk.