Digital colour imaging firm Kromek is planning to raise £15m ($23.7m) in an initial public offering (IPO) on London’s Alternative Investment Market (AIM).

Beginning life as a spin-out of Durham University in 2003 called Durham Scientific Crystals, the firm has grown to be valued at around £75m.

Kromek, which specialises in digital colour imaging for x-rays, plans to use money raised by the IPO to fund further growth.

The company is yet to make a profit, but has succeeded in…