Split mould tool - for foamed plastic components using semi-permanent mould release coating

摘要

To improve the surface finish of components which have a relatively thin non-porous skin and a porous internal structure either of structural foam or integral foam the inside faces of the split mould tools used repeatedly either for poured or injected material are coated with a cured layer of pref polyfluorolefin. This layer is not >0.1 mm thick esp. is 20-50 mu thick. It may be built up from part layers cured and allowed to cool before the next is applied. Curing temp. for them is >300 degrees C but below the temp. at which the polyfluorolefin is changed chemically. The low coeff. of friction between the coating and the plastic raw materials prevent drag etc.