摘要:
Some kinds of carboxylic acids have a stabilizing effect on metal alkoxides and, in a precursor solution, are unlikely to cause a reduced storage stability and an increased viscosity of the precursor solution even when their content is increased; they can be used in the solvent component of the precursor solution. The carboxylic acid content is preferably in a range of 20% by mass to 60% by mass, both inclusive, of the total amount of the raw materials used to prepare the precursor solution. The carboxylic acid component prevents the hydrolysis due to the moisture in the air when the carboxylic acid content is equal to or more than 20% by mass. When the carboxylic acid content is equal to or less than 60% by mass, furthermore, the resulting precursor film will have a sufficiently large thickness.