Silicon oxide-coated iron oxide composition for coating comprising iron oxide particles coated with silicon oxide

摘要

The present invention provides a composition for coating having high ultraviolet ray protection ability for a coating material, and properties required for a coating material such as texture, appearance, designability and weather resistance. The composition is a silicon oxide-coated iron oxide composition for coating comprising iron oxide particles, a primary particle diameter of which is 1 nm or more and 50 nm or less, wherein at least a part of the surface of said iron oxide particles is coated with silicon oxide, and wherein said composition comprises an iron oxide particle dispersion having the average molar absorption coefficient of 1500 L/(mol·cm) or more for the light of the wavelengths from 190 nm to 380 nm in a state that said coated iron oxide particles are dispersed in a dispersion medium. It is preferable that the transmittance of said iron oxide particle containing dispersion for the light of the wavelengths from 200 nm to 420 nm is 2.0% or less, and the transmittance of said iron oxide particle containing dispersion for the light of the wavelengths from 620 nm to 780 nm is 80% or more.