Moulded PU articles are made on at a time by injecting the polyurethane mixture into moulds. When the mixture rises and expands, it occupies the whole space in the mould, solidifies and the produced part can then be removed from the mould, either mechanically or manually. This makes it the preferred process for the production of parts with complex shapes, as it also allows for placing inserts into the mould for further easier assembly.
This technology is thus widely used in the automotive industry, for the production of seat cushions, seat back, armrests, headrests and knee cushions. There are several types of moulded foam production processes. The two main ones are hot and cold cure, which are both used for similar purposes. Hot cure used to be the generic production process for moulded foaming, but today’s dominant production process worldwide is cold cure foam, also known as high-resilience (HR) foam. A special processing technology called ‘pour in place’ has been developed in order to directly produce parts ready for use. It is used, for example, for the production of headrests.
For more information about production process of flexible moulded foam, see our brochure “Getting to understand moulded polyurethane foam for automotive seating”.
MOULDED POLYURETHANE PARTS
Transport and the automotive industry represent about 15% of total polyurethane demand. In light vehicles polyurethanes are the second-most used plastic, accounting for more than 20% of plastic used (in total around 28kg).
PU is used mainly in flexible foam, with around 75% in moulded foam and 25% in slabstock foam. Out of all polyurethane foam usage in the car, around 60% is used in seating (cushions, backrests), 10% in carpet underlay and headliners respectively, and ~3-5% in armrests and consoles, steering wheels, dashboard insulators and IP and door panels.