Method for creating field electron emission materials and devices

To create a field electron emission material, there is printed upon a substrate 1501 with an electrically conductive surface 1502, an ink 1503 comprising a major component of fluid vehicle; a first minor component of electrically insulating material, either ready formed or provided within a precursor therefor; and a second minor component of electrically conductive particles 1504. The printed ink is then treated to expel the major component and create the field electron emission material from the minor components on the substrate. The electrically conductive particles may be omitted, to print a solid, electrically insulating layer in a field emission device.