Had to search a bit, is this it?

> Overmolding is a multi-shot injection molding process that produces a single product from two or more different thermoplastics

> Overmolding enables the unification of the substrate material with the overmold material in a fraction of the time that it takes to join two or more parts together in a secondary operation on an assembly line

From https://sybridge.com/overmolding-overview/