| abstract |
A substrate (22) is provided with a layer (21) comprising organo-metallic components (23) in a solvent having a high-boiling point component (24). As the solvent is removed, the high-boiling point component phase separates, forming larger globules (26) in a matrix (25). The-high-boiling point component is thereafter removed, leaving a matrix (12) of a substance such as SiO2, in which cavities (13) filled with gas or air of vacuum are present. The cavities have sizes from 5 to 200 nm. |