| 摘要 |
PURPOSE:To provide the nontoxic, safe tin dioxide, free from blue-black color due to antimony, excellent in transparency in itself, and capable of giving any color tone through its combination with colorants. CONSTITUTION:The objective electrically conductive ultrafine tin dioxide consisting virtually of tin dioxide and containing no dopant, having the following characteristics: (1) particle diameter for D90 in particle size distribution: 0.01-5mum; (2) specific surface area: 5-100m<2>/g, and (3) volume resistivity: 10<-1>-10<4>OMEGA.cm. The ultrafine tin dioxide can be obtained by the following process: a reaction vessel is charged with a stannic salt solution and a neutralizing the solution separately and simultaneously, immediately followed by high-speed agitation of both the solutions together; in this case, the inside of the vessel is maintained at a specified constant pH level within the pH range of 2-12 and a precipitate is deposited, recovered, dried, and then baked in an inert or weakly reductive atmosphere to impart the objective tin dioxide with electrical conductivity. |
