sol–gel method colloid process solgel process sol-gel method sol-gel process CHMO:0001313 sol-gel processing solgel processing The process of the settling of (nm sized) particles from a colloidal suspension onto a pre-existing surface, resulting in ceramic materials. The desired solid particles (e.g. metal alkoxides) are suspended in a liquid, forming the 'sol', which is deposited on a substrate by spinning, dipping or coating, or transferred to a mould. The particles in the sol are polymerised by partial evaporation of the solvent, or addition of an initiator, forming the 'gel', which is then heated at high temperature to give the final solid product. sol–gel processing solgel method colloidal processing colloid method