| 摘要 |
<p>PURPOSE: To manufacture aerogel films the variations between, whose base materials are small by adjusting the gelation degree of the wet gel film of a wet-gel film bearing base material so that the wet gel film is subjected to supercritical drying with its gelation degree equal to a predetermined value, when starting its supercritical drying. CONSTITUTION: A supercritical-drying start controlling means (E) is the one, where when the gelation degree of the wet gel film of a wet-gel film bearing base material held by a holding means reaches a predetermined value, supercritical drying of the wet gel film is started. The reason that the wet gel film is subjected to a supercritical drying when its gelation degree reaches a predetermined value is based on the fact that its relation holding time to its degree of gelation, resulting in the one to the porosity of an aerogel film obtained by its drying is in a proportionate relation, and further, the one to the dielectric constant of the aerogel film is an inversely proportional relation. Even if the compositions of the raw-material liquids of the wet-gel films are made identical with each other and their film thicknesses are made identical with each other, the dielectric constants of the aerogel film created from them depend on their shelf times, i.e., their gelatinizing times, and the larger the gelatinizing times are, the larger the porosities of the aerogel films to make small the dielectric constants thereof. On the other hand, their gelatinizing reactions advance excessively, they become granule to make them unable to form their film formations.</p> |
