Glass mouldings appts. made of carbon contg. material - obtd. by carbonising cloth of cotton and resin

摘要

Appts. for forming glass has the parts coming into contact with the thermally softened glass made of a carbon contg. material produced by carbonisation of a hard fabric based as phenol or cresol resin and cotton fabric. The carbon material is made of layers of varius thicknesses having different permeabilities for gases. It is adapted to the functionof the mould by additional working, e.g. for use in blow moulding; the carbon is provided with cold water channels. Unwanted deformation such as occurs with vitreous carbon moulds with dense or porous surfaces, is avoided. Surface irregularities due to the porous surface are negligible or non-existent. The pore sizes are more readily controllable to give predetermined characteristics of pore size distribution and gas permeability.