How are plastic bottle caps made?

Every day, across the globe, millions of bottle caps are manufactured.  But not all bottle caps are created equal. 

Some are for child-proof pharmaceutical bottles, containing lifesaving, but often dangerous medications.  Others are used as lids for make-up remover or simply bottles of water.  In this post, we will explain how we manufacture our bottle caps here at Measom Freer.


Custom moulded bottle caps


No matter what its purpose, every bottle cap is manufactured in one of two ways – either by blow moulding or injection moulding, with the latter being far more common. 

  • Blow moulding is largely used for hollow objects.  This makes it ideal for plastic bottles, jars and containers.  Most thermoplastics can be used for blow moulding.  These include PVC, HDPE, rHDPE, LDPE, PETG, Bioplastics, rPP and PP.  We can blow mould plastic products with up to one litre capacity.
  • Injection moulding is the way that we manufacture most of our bottle caps.  Plastic products with a shot weight of up to approximately 350g can be created using this process.  Again, injection moulding can be used with most recyclable thermoplastic materials.


How are plastic bottle caps injection moulded?


This process involves high temperature melted plastic being injected into the mould.  The mould itself is typically made from durable stainless steel, and it can be used thousands of times.  The plastic is then pressurised, cooled, solidified, and finally taken out of the mould to form a plastic bottle cap. The caps will then be carefully separated from each other and prepared for further processing, for example wadding and sealing.

Injection moulding is extremely cost effective for large scale production.  This is because it offers high repeatability.  This means there will be no variation in the dimension, shape, or finish of the plastic bottle cap between individual caps, or even between batches. 

It’s common to use injection moulding to manufacture bottle caps, as a very high level of detail is required to achieve the accuracy required on the internal screw thread.


Embossing plastic bottle caps


Injection moulding can support high levels of detail, making it easy to emboss logos or company messages onto the lid.

Embossing on plastic bottle lids is the perfect way to attract the attention of customers.  Even if they have overlooked the label, they can’t overlook the lid as they need to open the bottle. Additionally, labels may wear off over time, but embossing will not.


How we work with you to create the perfect plastic bottle cap


Here at Measom Freer, we have all the latest CAD/CAM facilities.  We use these for component design, 3D visualisation and modelling of your plastic packaging and plastic bottle caps.

If needed, we can manufacture a prototype of the design you require so that you can ensure you’re happy with it before mass production begins. 


Find out more about our custom moulding services


We can design and create high quality, fully recyclable plastic bottles and caps that are tailored to your business.

Get in touch to find out more or to chat to us about your requirements. Call us on 0116 288 1588 or complete our contact form and we’ll get back to you as quickly as we can.

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