This process can be used to process thermosets and thermoplastics, although its use with the latter material is not all that common. This is because with thermoplastics the mould would need to be alternatively heated, to shape the materials, and cooled to permit ejection from the mould cross linking materials, on the other hand, may be ejected at the high mould tempeature. The best examples of the use of thermoplastics in compression moulding is the production of gramophone records from a PVC co-polymer and the moulding of contact lenses from acrylic.

However, the major advantages of compression moulding is that it is a simple process with little waste and therefore is particularly suitable for materials that cross-link during processing. By the nature of process there are no parts where prematurely cured material can get trapped and cause prolonged down-time.

Basically a compression moulding system consists of matched male and female dies which are heated to temperatures between 125°C -200°C. A pre-weighed charge of the material to be moulded is placed between the two mould halves and these are then closed. Under the heat and pressure, the polymeric material plasticizes flows to the shape of the mould and becomes cured. The mould split lines is usually horizontal and the mould is closed by means of a high pressures using hydraulic press. Due to the high pressures involved in this process, the mould must be made fully hardened tool steel. Also, as cycle times are slow (30-60 seconds) in comparison with injection moulding, it is a normal practice to use multicavity moulds in order to increase production rates. This additional complexity plus the highly polished, high precision nature of the moulds mean that mould costs are high. The limitation of the process that insert or complex shapes cannot be produced. The most popular application is melamine table ware and gift articles from thermosetting resin thrown this process.