TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: Step (A) involves mixing together to form a liquid composition of compound (0.1-15, preferably 0.1-10, especially 0.1-5 vol.%) comprising Si and O; polymeric glycol (0.1-80, preferably 0.1-15, especially 0.1-10 g/l); strong acid (0.1-20, preferably 0.1-15, especially 0.1-10 g/l); at least one alcohol (0.1-80, preferably 0.1-20 vol.%) having higher boiling point than at least one other alcohol contained in the composition; and other alcohol (balance). During the mixing, ratio (vol.%) of the polymeric glycol per liter of composition to the compound comprising Si and O is at least 1. Step (B) involves dipping, brushing, spinning or spraying (preferably spraying) the composition onto the surface of the substrate to form the liquid film. During the step (B), the substrate is at room temperature (preferably greater than or equal to 50 degrees C) and atmospheric pressure; and the liquid composition is at room temperature (preferably greater than or equal to 50 degrees C). In step (C), the evaporation of the alcohols (preferably at least on alcohol and ethanol) takes greater than or equal to 60 seconds. In Step (D), the heating is at 500-800 degrees C. After heating, the film is 700 Angstrom to 2000 mu m (preferably 700-1400 Angstrom ) thick, and porous. Preferably the liquid composition comprises tetraethyl orthosilicate (0.1-10 or 0.1-5, preferably 1-3 vol.%), solution (0.1-20 vol.%) of polyethylene glycol (30 or 0.231-20, preferably 4.6-6.9 g) in 100 ml of water, solution (0.1-2 vol.%) of HCl (37 wt.% or 0.444-8.88, preferably 1.78-2.66 g) in water, at least one alcohol (0.1-80 or 0.1-20, preferably 1-20 vol.%) having higher boiling point than ethanol, and ethanol (balance), where during the mixing, ratio (vol.%) of the solution of polyethylene glycol (30 g) in water (100 ml) to the tetraethyl orthosilicate is at least 0.5. Preferred Components: The compound comprising Si and O is selected from silanes, silicates, siloxanes and silanols (preferably tetraethyl orthosilicate).    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The strong acid is nitric acid, hydrochloric acid, sulfuric acid or hydrobromic acid (preferably hydrochloric acid or nitric acid). The at least one alcohol comprises monohydric alcohol. The first alcohol is ethanol, and the second alcohol has boiling point that is higher than the boiling point of ethanol, where the second alcohol is selected from propanol, butanol and pentanol (preferably n-butanol).    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The polymeric glycol is selected from polyalkyl glycols and polyalkylene glycols (preferably polyethylene glycol). EXAMPLE - A liquid composition was prepared by mixing together tetraethyl orthosilicate (TEOS) (2 vol.%), solution (4 vol.%) of polyethylene glycol (PEG with weight average molecular weight of 8000) (30 g) in water (100 ml), solution (1 vol.%) of HCl (37 wt.%) in water, n-butanol (5 vol.%), and ethanol, where ratio of PEG to PEOS was 2. The liquid composition at room temperature was sprayed in air onto at least one surface of glass sheet at room temperature to forming liquid film. The ethanol and n-butanol evaporated from the liquid film for 90 seconds to obtain solid film. The solid film was heated to 700 degrees C for 2 minutes to form silica film with light transmission of 4%.