Glass is the conventional way of providing cheap, stable durable protection for drivers whilst maintaining good visibility but glass is also heavy, difficult to shape, potentially very unfriendly to passengers if it fails during a crash, and is one of the easiest points of access to a vehicle for intruders.

    A plastic alternative would greatly ease these problems and indeed polycarbonate replacements have been experimented with but until now it has been difficult to find any reasonably durable plastic that has good scratch resistance, and weathers well while still giving good visibly.

    Researchers in the Warwick Manufacturing Group at the University of Warwick, led by Kerry Kirwan, have solved this problem by using an injection moulding process which creates a window with a light, impact resistant polycarbonate core surrounded by a tougher plastic skin which is much more scratch resistant and weather proof. The materials compliment each other providing durability while remaining optically clear. For a similar cost, drivers can thus now have vehicle windows which are:

• Lighter in weight thus making vehicles more fuel efficient
• More resistant to attempts by intruders to gain entry into a vehicle
• More friendly to occupants during crashes
• Easier to shape, opening up more design possibilities
• More easily recycled at the end of a car's life