Whether you're looking for rubberised grips or in-moulded light guides;
two-shot injection moulding is the most sophisticated way to combine two different polymers in a single component.
TWIN-SHOT / MULTI-SHOT / 2K
It's a process with many different names around the globe, but should not be mistaken for lesser techniques.
The key advantage of two-shot, is the cohesive bond between polymers (or elastomers), which provides a level of strength between substrate and second-shot that is not possible with lesser techniques.
A vast range of polymers and elastomers can be chosen from to create a wide array of end-results. Soft touch surfaces, contrasting colours, clear windows, LED light guides, IP seals and flexible buttons are all great examples of the endless possibilities!
A COHESIVE BOND
With two-shot there is a better interface between the plastics, because the initial injected substrate is free from surface contaminants within the mould (enhancing adhesion) and also retains a high level of thermal energy (heat), improving the melt flow of the second shot.
Another advantage of the two-shot process over that of over-moulding relates to a reduction in post-mould-shrinkage of the substrate, as it is retained on the core-side of the mould until the cycle is completed with ejection.
ACCURATE & REPEATABLE
With two-shot moulding, the substrate commonly remains on the core side of the tool in a fixed and well-indexed location. When the second shot cavity closes against the substrate a highly accurate shut-out is achieved, which is not so feasible within the over-moulding process.
Once the process has been established, the two-shot process also lends itself well to an automated cycle, as no operator involvement is necessary.
This makes two-shot the perfect choice for complex, multi-material, and multi-coloured components or products where the cosmetic finish needs to be seamless and free from visual defects.
With two-shot you can achieve:
reduced unit cost
faster cycle time
reduced waste and risk of damage
single process with no manual intervention
fewer assembly defects
enhanced product quality