At first glance, putting holes in a perfectly good polythene bag seems a bit daft – but for certain products, a completely sealed environment is actually the worst thing you can do. But micro perforated polythene bags use precision-engineered holes to create a controlled atmosphere that keeps products fresher for longer. This is called Modified Atmosphere Packaging, or MAP packaging for short, and it’s a genuine game-changer for packaging.
What is MAP packaging?
MAP, or Modified Atmosphere Packaging, allows manufacturers to actively manage the atmosphere inside a package. Instead of just trapping whatever air happens to be in the environment, you can flush it out and replace it with something else. This is useful for all kinds of applications.
With micro perforated films, the bag becomes a dynamic environment, where gases can move in and out at a carefully controlled rate.
For fresh produce like salad leaves, herbs, mushrooms, and broccoli, these are still alive when they go into the bag. They’re still “breathing” – and in a standard sealed bag, waste gases build up fast. The humidity skyrockets, condensation forms, and before you know it, you have a soggy, mouldy mess.
But it’s not just foodstuffs that benefit. Any products that need a controlled atmosphere, like pharmaceuticals and healthcare goods, need to be packaged in a way that extends their lifespan and performance.
Micro perforated polythene bags achieve this by creating a tiny escape route for unwanted gases, and a method for displacing them with inert gases when filling. The holes are so small (measured in microns) that they allow for gas exchange while still keeping dirt, insects, and most microbes firmly outside.
This creates packaging that is breathable, without being vulnerable.
Micro perforated versus regular perforated packaging
The size of the perforation in your packaging changes its use cases, and getting it right for your specific product is essential.
Normal, “macro” perforation is what you will see on hardy goods – like potatoes, or even things like pillows and lightweight aggregate materials. These are large holes that you can see with the naked eye, and they let a lot of air flow through. Hardy products benefit from good ventilation to stop moisture building up while keeping the majority of dirt out. But those same large holes would be a disaster for something delicate.
Micro perforation for sensitive products
Micro perforated film is a different kettle of fish. These holes are often invisible to the naked eye, created using precision lasers or fine needles. These tiny perforations allow for a gentle, measured gas exchange.
For delicate items like fresh food, sensitive electronic equipment, and pharmaceuticals, this level of control is essential. The holes are small enough to maintain a controlled environment, free of contaminants – but large enough to let unwanted gases escape. It’s a “breathing system”, designed specifically for the product inside.
The benefits of micro perforated polythene bags for MAP
So why go to all this trouble? What do micro perforated polythene bags actually give you that standard bags can’t?
Extended shelf life, reduced waste – same strength
By matching the bag’s breathability to the product’s respiration rate, you can dramatically slow down the ageing process. For example, foods that might last two days in a standard bag can easily last five or six days in the right breathable packaging, especially if the “bad” gases are flushed out first. For businesses, that means less spoilage, fewer wasted products, and happier customers.
Even with all those microscopic holes, the bag doesn’t become weak or useless as a barrier. The holes are so tiny that the overall structure of the polythene remains strong. It still protects against physical damage, still resists tearing, and still acts as an effective barrier against liquid, dirt, and pests.
You get the best of both worlds – breathability where you need it, and toughness where you want it.
Perfect for a huge range of products
We have talked a lot about food and fresh produce – because it’s a familiar area that most of us can understand, and have probably experienced MAP packaging associated with it. But the applications go far beyond food. Micro perforated polythene bags are brilliant for medical and pharmaceutical applications, where controlled gas exchange is needed for product stability.
In the healthcare sector, micro perforated polythene bags are used for packaging sensitive pharmaceuticals and medical devices. The controlled airflow helps maintain product integrity and prevents moisture buildup. Regulatory bodies can even mandate packaging that allows gas exchange in some applications, and adoption is growing in hospitals and pharmaceutical manufacturing units globally.
Enhanced customer experience
Because micro perforated film has good clarity and can be printed with high precision, your products look fantastic. Customers can see exactly what they’re getting, and the packaging feels high quality.
How micro perforation is made: lasers and needles
Getting the perforation right is a precision job. For most applications, fine needles are used to create consistent, tiny holes at a set spacing. This is cost-effective and works well for a huge range of products.
Read more – How is microperforated film made?
But for the most demanding applications, laser perforation is the gold standard. A laser can create holes that are incredibly consistent, measured in microns – with exact precision. This allows packaging engineers to calculate the exact gas transmission rate needed for a specific product. This is real material science, and it produces the very best results for sensitive, medical, or high-value goods.
Getting started with custom micro perforated polythene bags
If you work in food packaging, pharmaceuticals, or create highly gas-sensitive equipment, then switching to micro perforated polythene bags could transform your business.
And working with an experienced polythene manufacturer makes all the difference.
At NPF Packaging, we specialise in creating custom micro perforated polythene bags tailored to your exact needs. We can design a packaging solution that keeps your products in perfect condition. We’ll also advise on the best polythene thickness and blend for durability and clarity.
Upgrade your packaging
Switch to micro perforated polythene bags today, with the experts at NPF Packaging. Get a quote now, or call us on 01773 820415 to get started.