Miscellaneous Materials

Abstract

Where resin systems are processed by hot press moulding, transfer or injection moulding, and particularly where sheet and dough moulding compounds are processed by these techniques, it is a considerable disadvantage to have to apply release agent to the mould either between each moulding or after several mouldings have been made. This can be overcome completely by the use of internal release agents in the moulding compound. Thus automatic moulding lines can be operated in a similar way to those used for processing thermoplastic materials. With a new mould, the application of an external release agent to the mould surface may be necessary for the first few mouldings, until sufficient thickness of release agent has been built up and the mould run-in. After this no further application of release agent should be necessary.