| 摘要 |
PURPOSE: To obtain a new solid writing material having a specific effect of developing a transparent or white written line into a clear and colored line in exposure to ultraviolet light rays, containing a substance emitting a color, under ultraviolet rays, different from a color in an ordinary state, by dispersing the substance. CONSTITUTION: This product contains preferably 10-40wt.% of a substance emitting a color, under ultraviolet rays, different from a color in an ordinary state based on the whole amount of writing materials and is obtained by dispersing the substance. For example, Sr2 P2 O7 :EU emitting in blue, ZnO:Zn emitting in bluish green, Zn2 GeO4 :Mn emitting in green, ZnS:Mn emitting in orange and Y2 O3 :Eu emitting in red may be cited as the substance. The average particle diameter of the substance is preferably 0.5-10μm in terms of coloring. A binder such as PVA, an extender material such as talc, a wax and a lubricant can be used as materials of the solid writing materials except the substance. |
