What is the difference between blow molding and injection molding?

What is the difference between blow molding and injection molding?

In-mold labeling (IML) is an attractive choice for a lot of today’s leading brands. Companies are leveraging the power of in-mold labeling with anything from chilled dairy products to laundry detergents and motor oil.

When discussing AR Metallizing’s IML solutions, some of the most frequently asked questions include:

  • What are the key differences between blow and injection mold applications?
  • How are AR Metallizing’s grades optimized to perform at both the printer and labeling lines? 

Blow molding

Blow molding is used to produce containers or bottles that are made of plastic and are hollow – think household cleaning products or liquid laundry detergent. A plastic tube is heated until it inflates – imagine blowing up a balloon. A mold is then clamped down around the plastic to give it it’s final shape. The mold will already have the label inside it, with the back side of the label facing the oncoming hot plastic (so that the label is the right way around on the final container). The residual heat from the plastic fuses the label to the container.

Blow molding is typically used for applications such as: Bottles for products like detergent, liquid soap, shampoo, motor oil, milk etc.

Injection molding

With injection molding, plastic is again used to make containers which are plastic and hollow. During the injection molding process, the heated plastic is injected under high pressure into a mold which contains the label(s). The hot plastic cools off and hardens with the label then seamlessly attached without glue.

Injection molding is typically used for applications such as: Ice cream tubs, dishwasher tablet tubs, yogurts, dairy products etc.

Why explore AR Metallizing IML solutions:

AR Metallizing utilizes substrates that allow proper airflow during converting and label application.  Our top coatings have been thoughtfully for performance and beauty.  Our coatings are designed to achieve an optimal CoF which allows for smooth converting, as sheets are fed into the presses.  The top coating contains the magic for great ink adhesion. 

Additionally, AR Metallizing’s vacuum metallized IML labels can be made of the same material as the packaging vessels, allowing the finished product to be fully recyclable.  This is desirable to clients looking to develop sustainable, landfill free packaging solutions.  In addition, as IML labels are formed into the vessel structure, the labels are able to withstand the significant changes to humidity and temperature without losing their luster or beauty.  This makes them an excellent solution for frozen or refrigerated items. 

Our products for IML

AR Metallizing’s product portfolio contains solutions that are ideal for both blow mold and injection mold applications. Our team proudly works extensively alongside base material suppliers, printers, and bottlers molders to ensure our product is tailored for their set up so together we can deliver an absolutely perfect product to the end customer.

More questions?

If you have any questions, queries or comments, we'd love to hear from you! Drop us a note, and one of our team of IML experts will be in touch.


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