Self-healing glass: a cracking discovery from Japan

TOKYO: A Japanese researcher has developed — by accident— a new type of glass that can be repaired simply by pressing it back together after it cracks.

The discovery opens the way for super-durable glass that could triple the lifespan of everyday products like car windows, construction materials, fish tanks and even toilet seats. Yu Yanagisawa, a chemistry researcher at the University of Tokyo, made the breakthrough by chance while investigating adhesives that can be used on wet surfaces.

Does this mean you will soon be able to repair those cracks in your smartphone with a quick press of the fingers? Or surreptitiously piece together a shattered beer glass dropped after one pint too many? Well, not quite.

Not now and in fact, not in the near future. But it does open a window of opportunity for researchers to explore ways to make more durable, lightweight, glass-like items, like car windows.

In a lab demonstration for AFP, Yanagisawa broke a glass sample into two pieces. He then held the cross sections of the two pieces together for about 30 seconds until the glass repaired itself, almost resembling its original form.

To demonstrate its strength, he then hung a nearly full bottle of water from the piece of glass — and it stayed intact. The organic glass, made of a substance called polyether thioureas, is closer to acrylic than mineral glass, which is used for tableware and smartphone screens. Other scientists have demonstrated similar properties by using rubber or gel materials but Yanagisawa was the first to demonstrate the self-healing concept with glass.