Saflex is Solutia's brand of polyvinyl butyral (PVB) used to make laminated glass. A layer of Saflex protective interlayer is bonded together between two panes of glass under heat and pressure. Once sealed together, the glass "sandwich" behaves as a single unit and looks like normal glass. Annealed, heat-strengthened or tempered glass can be used to produce laminated glass. Laminated glass may crack upon impact, but the glass fragments tend to adhere to the protective interlayer rather than falling free and potentially causing injury. Benefits of laminated glass include safety, security, sound control, solar energy performance, ultraviolet screening, and protection from hurricanes, earthquakes and bomb blasts.