injection moulding

Injection moulding – a quick guide

Injection moulding is popular because of its versatile, virtually limitless application and consistent results. It forces molten polymer at high pressure into a mould cavity. The plastic then hardens to the shape of this cavity and the component can be ejected.

infographic - injection moulding
  • Key advantages
    • Mould designs produce parts that are highly precise and dimensionally accurate
    • Consistent wall thickness offers stability for hot fill and microwaveable products
    • Packaging component cycle times are highly efficient with most at less than 20 seconds
    • All excess material can be ground up and re-used, generating no waste
    • Materials and/or colours can easily be changed according to your needs
    • Moulding equipment is automated delivering reduced costs
    • Suitable for high volumes with manufacturing efficiency
    • Moulded parts are produced with high-quality surface finishes, requiring no further processing
  • Examples
    • PP thin-walled tamper-evident containers for chilled soups
    • Shaving gel actuators
    • Over caps for Barista style coffee
    • Multi-chamber jars for baking decoration
    • Crystal clear clarity for thick-walled jars used in luxury personal care ranges
    • Two-element sauce bottle screw caps with dosing plugs
    • Child-resistant closures
    • Hermetically sealed toilet cleaners
    • Specialist plugs for use in sauce dispensers for fast-food retail
  • Value add and materials


    In mould labelling (IML), post-mould labelling, shrink sleeving, robotic collation and stacking, induction heat seal liners (IHS), assembly and ultrasonic welding, and UV inhibitors, and coatings such as for lubricating line feed.


    Homo and Copolymer PP and rPP, LLDPE, HDPE and PET.

Outline of a stag

“Robinson offered reliability, quality and worked at pace to meet our growth aspirations.”

Blake Hoover, Product Manager, Huhtamaki
1001 Carpet care

Case Study – 1001

WD40 turned to Robinson in 2019 for its expertise in supporting the evolution of the 1001 Carpet Fresh brand. At the heart of this evolution was the innovation of our ‘spray through’ cap. Allowing consumers to activate the product directly through the cap, thereby negating the need for its removal, would undoubtedly be a step-change in the improved consumer experience.

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Closures & overcaps range

Caps, closures and overcaps

We offer the convenience and assurance of the total packaging solution consisting of a cap and container. We know this is valued by our customers who prefer a simplified supply chain and a single trusted supplier for all packaging and packaging components.

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Outline of a stag

“The result of working with Robinson is the successful development of a technically demanding component.”

Omar Warrak, Supply Chain Project Manager, WD40 Company