This is the original patent issued to Owens Corning in 1940 for what is known as Fiberglass, this patent has saved trillions in energy costs. Manufacture
of glass fibres or filaments by drawing or extruding, e.g. direct
drawing of molten glass from nozzles; Cooling fins therefor from molten
glass in which the resultant product consists of different sorts of
glass or is characterised by shape, e.g. hollow fibres, undulated
fibres, fibres presenting a rough surface.