Solgels are colloids, or liquids with uniformly dispersed solid particles (like milk) that are converted to gel form.

FORBES: The Science of Small

This is fine for making uniform materials, but not so good if detailed structure is required which is where the colloids come in.

ECONOMIST: A new way to build complicated materials, micron by micron

As the team reports in a forthcoming issue of Langmuir, a journal devoted to the study of colloids, the new technique allows them to build composite materials with custom-designed features as tiny as the diameter of a human hair.

ECONOMIST: A new way to build complicated materials, micron by micron