Forming protective layers on glass panes - to prevent scratching during storage and comprising strings of solidified plastics or wax

摘要

Glass panes are provided with cord-shaped intermediate layers by allowing a stream of liq. plastic to fall at least intermittently onto a pane on which the plastic solidifies or hardens. The plastic is either a meltable adhesive contg. paraffin wax or other non-polar cpds.; or a two-component foamable plastic. The glass panes pref. move along a conveyor underneath a vessel heated to a controlled temp. and contg. bottom outlet holes through which streams of the plastic flow via shutter valves controlled by magnets. The leading edge of each pane triggers a switch so the valves open, whereas the back edge of each pane causes the valves to close. Arrangement is used for stacking glass panes, where the layers prevent direct contact between the panes and thus obviate scratches on the surface of the glass. The deposited plastic remains on the panes even when the latter are tilted to a vertical position.