Dielectric film, method for manufacturing the same, and transducer including the same

A method for manufacturing a dielectric film, the dielectric film including an elastomer and metallic oxide particles having a particle diameter of 100 nm or less that are chemically bonded to the elastomer and are dispersed in the elastomer in a state of primary particles, the metallic oxide particles containing TiO2/ZrO2 complex particles or TiO2/SiO2 complex particles, the method comprising:

• a chelating process of adding a chelating agent to a titanium alkoxide compound to produce a chelate compound of the titanium alkoxide compound;
• a sol manufacturing process of adding any one of a zirconium alkoxide compound, a chelate compound of the zirconium alkoxide compound, and a silicon alkoxide compound, and then an organic solvent and water to the chelate compound of the titanium alkoxide compound to obtain a sol of TiO2/ZrO2 complex particles or TiO2/SiO2 complex particles having a hydroxy group produced by hydrolytic reaction of the titanium alkoxide compound and a zirconium alkoxide compound or a silicon alkoxide compound;
• a mixed solution preparing process of preparing a mixed solution containing the sol of the TiO2/ZrO2 complex particles or the TiO2/SiO2 complex particles and a polymer solution containing a rubber polymer having a functional group that optionally reacts with a hydroxy group;
• and
• a film forming process of applying the mixed solution onto a substrate and curing a resultant coating film to obtain a dielectric film.