Aq. slip and mould-release agent for tyre mfr.

摘要

An aqueous slip and mould-release agent for the mfr. of tyres and other rubber articles contains a) 0.5-6 wt.% pref. 1.5-4.0 wt.% polytetrafluoroethylene (PTFE); b) 20-40 wt.% pref. 25-35 wt.% esp. 27-32 wt.% mineral fillers; and c) 40 wt.% pref. 60 wt.% and esp. 65-75 wt.% water. Also claimed is the process for moulding and vulcanisation of tyres and other rubber articles. Negative moulds are pressed, in a press, into the blank with the help of a heating membrane under high pressure and vulcanisation is effected. Prior to the moulding and vulcanisation, the aq. slip- and mould-release agent is sprayed on the inside of the tyre blank and the water contained in it is allowed to evaporate, accompanied by development of a film of slip-and release agent.