Curved laminated windscreens for automobiles - made using intermediate polymer foil shaped by winding hot foil onto conical mandrel

摘要

A foil strip is continuously heated to its stretching temp. and is then stretched by a variable amt. in the transverse direction, followed by laminating the foil between two curved glass panes. Stretching is carried out on a conical drum, onto which the foil is wound. The foil is pref. thermoplastic, esp. polyvinyl-butyral foil, heated to 40-60 degrees C for stretching. The foil pref. has a dyed or coloured zone running along one edge, i.e. to make a tinted upper zone on the windscreen. The coil of foil on the drum is pref. heated to 60-90 degrees C in an oven to remove the stress caused by stretching.