What is the difference between cast and blown stretch wrap?

What is the difference between cast and blown stretch wrap?

To find the perfect stretch wrap for your business needs, you must first understand what is the difference between cast and blown stretch wrap? At Lindum Packaging, we deal with these kinds of questions every day and are glad to help you choose the right stretch film for you operations – whether that’s cast or blown stretch wrap

There are two types of stretch wrap: blown and cast stretch wrap. Both types are used for wrapping and protecting your goods… and different loads determine which is the best type of wrap for the job. But what is really the difference between cast and blown stretch wrap? And how do you determine which is the best type for the job?

The difference in the manufacturing

The first difference between cast and blown stretch wrap is the manufacturing process. Cast stretch wrap is made through cast extrusion, starting with a granular resin poured into a heated screw barrel. Molten resin is continuously poured through a narrow slot die onto a chilled roller. The chilled roller quickly solidifies and cools the film.

Blown stretch wrap is created similarly with granular resin being poured into a heated screw barrel. The resin is then forced into a circular die and vertically blown upward and outward. The film is gradually cooled, giving the wrap a hazy appearance. 

Cast vs blown stretch wrap: the benefits of each

The different manufacturing processes affect the characteristics of the film. Therefore, meaning specific types of film could be suited specifically to certain purposes. So, what is the difference between cast and blown stretch wrap when it comes to the benefits of each? 

The benefits of cast stretch wrap

  • High transparency 
  • Provides a barrier for moisture, gases, and aromas
  • Requires less strength to stretch
  • Tear-resistant
  • Unwinds quietly.

The benefits of blown stretch wrap

  • Significant load holding
  • Highly puncture-resistant
  • A higher degree of memory when stretched
  • Durable
  • High level of cling.

When to use cast or blown stretch wrap

Cast vs blown stretch wrap ー which is the best choice for your packaging operations? It is crucial to choose the right type as the wrong type of film could lead to product damage or damage during transportation, and it can also lead to other problems such as difficulties scanning barcodes. So, take a moment to think about what you need the stretch film for.

In a warehouse environment

If you use a barcode scanner to scan goods in a warehouse setting, then the difference between cast and blown stretch wrap is an important question. The transparency of the cast stretch wrap makes it easier to scan the pallet than the more dull blown film. Therefore, the cast stretch wrap is the best option if your goods should be used along with a barcode scanner or need to be identified quickly. 

To increase pallet stability

Blown stretch wrap is more robust and resilient than cast film and offers better stretch capacity. Therefore it is the best choice for securing pallets of goods, especially if the palletised goods has sharp edges.

When excellent resistance is needed 

When puncture resistance is essential, the blown film would be the best choice. Even though blown stretch wrap is more resistant to breaking, cast film is not a bad choice either since it only tears when exposed to a significant amount of stress. 

When a quiet work environment is preferable

If you need reduced noise in your work environment, choose cast film since it unwinds quietly from the stretch roll when compared with blown film. Therefore, the reduced noise level of cast film provides a low-noise stretch film option.

Cast or blown stretch wrap ー why choose? 

Hopefully this has given you some pointers as to what is the difference between cast and blown stretch wrap. However, if you aren’t sure which stretch film type is the best for your business and packaging operations, then contact us and talk to one of our experts to discuss the differences and advantages of our stretch film range. We have a wide selection of stretch films, so we can guide you on which is best suited to your packaging operations. Whether you require cast or blown stretch wrap, we can guide you to the best film to suit your requirements.