| 摘要 |
A colloidal-sized agglomerated zinc oxide material having an average agglomerate size below 100 nanometers (nm) and method for production are disclosed. Preferably, the agglomerate size is below 60 nm. The colloidal zinc oxide material will transmit more than 75 %, and preferably more than 85 % of the light in the visible range of the spectrum (i.e., light between 390 and 800 nm in wavelength) and less than 5 % and preferably less than 3 % of light having a wavelength in the ultraviolet range between 190 and 390 nm when tested at 0.1 weight percent in mineral oil. The material is formed by first heat treating zinc carbonate to produce zinc oxide. This zinc oxide is then combined with a polyacrylic acid dispersant and milled to produce a colloidal sized zinc oxide material. |
