Window Patching: A Package’s Store Front

What is window patching?

Window patching involves applying a thin plastic film to a die-cut window on any box or packaging.

This enables customers to view the product without opening the package, and is commonly used to display luxury products.

Allowing potential customers to view your product gives them confidence in their purchase, which boosts purchasing power.

However, the decision to add a film patch depends on the nature of the product. Window patching is most effective for products with high visual appeal, such as high-end products.

Window Patching Films

If you have decided to use window patching in your packaging, it is worth noting that various types of film can be used to determine the most suitable material for your product.

Other than paperboard, plastic is one of the most widely used packaging materials, particularly polyethylene terephthalate (PET) and polyvinyl chloride (PVC).

PET film can be moulded into the required shape and then undergoes a drying process to provide additional protection.

High-reinforcement PET is also very strong, offering a tamper-proof film with excellent resistance to daily wear and tear.

PET plastic is lightweight and therefore susceptible to scratches, but strong enough to withstand external pressure and protect the contents of the packaging.

PET film is safe for storing food and is widely used in electronics, retail and other consumer products.

Alternatively, PVC film has a stronger exterior and a more damage-resistant surface, but it is not as environmentally friendly.

Although PVC film is resistant to interference and natural factors, it can degrade over time when exposed to UV rays. This degradation results in an unpleasant odour and ripples on the surface, making it unsuitable for food packaging.

However, despite the fact that PVC and PET film are the most widespread materials used for window packaging, other options still exist.

• Polypropylene is the most popular material for packaging sweets, snacks and baked goods.

• Glassine is used for high-grease products.

• Polyethylene is used for frozen food items.

• Polyolefin is used for shrink-wrapping pizza and boxed candies.

• Food products that are sensitive to light and air are best laminated with foil.

The window patching process

Now that you have a better idea of the films available for your package, it is time to consider the patching process.

At the heart of this process is a window patching machine.

The most popular machines are made by the well-known manufacturer Heiber + Schroder or the specialist manufacturer Kohmann.

These machines roll the windows onto a reel with a plastic film of your choice (PET, PVC, etc.).

The package is passed through the reel at a speed of around 375 m/min, during which time the machine adds the film to the packaging using electromagnetic energy.

Depending on the type of machine used for window patching, the plastic film will normally adhere immediately to the packaging material without any drying period.

This means that your package is ready as soon as it comes out of the machine, so your printing is completed easily and quickly.

However, other print finishing methods are available. These include: Embossing and debossing, soft touch coating and lamination, foil stamping and spot UV.