| 摘要 |
PURPOSE:To provide the above color developer which is improved in the dispersibility of a coloring agent into a binder resin, has the excellent transparency when superposed and has the excellent transparency when transferred and fixed onto an OHP sheet by adding 0.1 to 5.0pts.wt. hydrophobic silica into the binder resin. CONSTITUTION:The amt. of the hydrophobic silica to be added to the color developer compsn. formed by melting and kneading at least the binder resin, the coloring agent consisting of dyes or pigments of chromatic colors and the hydrophobic silica is specified to 0.1 to 5.0pts.wt. per 100pts.wt. binder resin. The binder resin is not particularly limited and all known resins are usable. For example, styrene, such as polystyrene, poly p-chlorstyrene and polyvinyl toluene, and the independent polymer of the substitution production thereof, etc., are used. The amt. of the hydrophobic silica to be internally added is required to be the range where the coloring agent is sufficiently dispersed and the preferably range thereof is 0.1 to 2.0wt.%. The effective result is not substantially obtainable if the amt. of the addition is below 0.1pt.wt. There is the tendency of the generation of such various problems as indicated in the prior art if the amt. of the addition exceeds 5.0pts.wt. and, therefore, such range is undesirable. |
