The beauty of 2 plastic,2 colors, 2 feelings
Double injection mould, sometimes referred as over-mould injection is mainly used to make one part of two different plastics and/or colors.First inject plastic of higher melting point, then the other plastic of lower melting point.Therefore the 2nd injection wont affect the 1st injection result. In most cases, the 2nd plastic is soft plastic like TPU/TPE etc. TPU/TPE has lower melting point and soft touch.
The purposes of double injection mould are basically used for:
Soft and firm touch
There are 2 common kinds of double injection molds.1 is to injection 2 plastics in the same injection machine,rotation-ally, which is more efficient and fast ; 2 is to separate them into 2 molds ,which is lower in tooling cost.