Dispersoid having metal-oxygen bonds, metal oxide film, and monomolecular film

Abstract

Dispersoids having metal-oxygen groups that are suitable for the production of metal oxide thin-films at a low temperature of 200° C. or below and for the production of homogeneous organic-inorganic hybrid materials. The dispersoid having metal-oxygen bonds may be obtained by mixing a metal compound having at least three hydrolyzable groups with at least 0.5 mole but less than 2 moles of water per mole of the metal compound in an organic solvent, in the absence of an acid, a base, and/or a dispersion stabilizer, and at a temperature at or below the temperature at which the metal compound begins to hydrolyze, then raising the temperature to at least the temperature at which hydrolysis begins.

1 . A method for producing a metal oxide film, comprising:
 applying a dispersoid that forms a metal oxide film to a substrate by coating or spraying;   wherein a transmittance of the dispersoid, expressed as a spectral transmittance measured at a dispersoid concentration of 0.5 wt % of oxide basis, at a quartz cell light path length of 1 cm, using an organic solvent as a control, and at a light wavelength of 550 nm, is 80% to 100%.   
     
     
         2 . The method of  claim 1 , wherein the metal oxide film is produced by drying at a temperature of 200° C. or below. 
     
     
         3 . The method of  claim 1 , wherein a surface of the metal oxide film has an average roughness of 10 nm or less. 
     
     
         4 . The method of  claim 2 , wherein a surface of the metal oxide film has an average roughness of 10 nm or less. 
     
     
         5 . A method for producing a metal oxide film, comprising:
 applying a dispersoid that forms a metal oxide film to a plastic substrate by coating or spraying;   wherein:   a transmittance of the dispersoid, expressed as a spectral transmittance measured at a dispersoid concentration of 0.5 wt % of oxide basis, at a quartz cell light path length of 1 cm, using an organic solvent as a control, and at a light wavelength of 550 nm, is 80% to 100%; and   the metal oxide film has a carbon content, expressed as an atomic ratio, of 10% or less.   
     
     
         6 . A method for producing a monomolecular film, comprising:
 forming a metal oxide film on a substrate, and then   contacting the metal oxide film with a metallic surfactant having at least one hydrolyzable group;   wherein:   the metal oxide film is produced from a dispersoid; and   a transmittance of the dispersoid, expressed as a spectral transmittance measured at a dispersoid concentration of 0.5 wt % of oxide basis, at a quartz cell light path length of 1 cm, using an organic solvent as a control, and at a light wavelength of 550 nm, is 80% to 100%.   
     
     
         7 . A method for producing a monomolecular film, comprising:
 using a dispersoid having metal-oxygen bonds that are stably dispersed without aggregation in an organic solvent in the absence of at least one selected from the group consisting of an acid, a base, and a dispersion stabilizer, or   using a solution containing the dispersoid, to form a metal oxide film on a substrate, then contacting the metal oxide film with a metallic surfactant having at least one hydrolyzable group;   wherein:   the metal oxide film is produced from a dispersoid; and   a transmittance of the dispersoid, expressed as a spectral transmittance measured at a dispersoid concentration of 0.5 wt % of oxide basis, at a quartz cell light path length of 1 cm, using an organic solvent as a control, and at a light wavelength of 550 nm, is 80% to 100%.