| 摘要 |
PURPOSE:To raise the speed and density of coloration as well as the fastness of color pictures by a method in which a specific semi-synthetic solid acid is used as a color former for a coloring sheet for pressure-sensitive recording and p-hydroxybenzonitrile is added to the coloring layer. CONSTITUTION:A clay mineral having a right tetrahedral laminar structure of silica is treated with an acid in such a way as to make SiO2 content 82- 96.5wt% on dry basis. Then acid-treated clay mineral is brought into contact with a magnesium and/or aluminum compound in an aqueous medium in such a way as to introduce a magnesium and/or aluminum component into the clay mineral and then dried to obtain a semi-synthetic solid acid. One hundred pts. of the semi-synthetic solid acid is mixed with 10-100pts. p-hydroxybenzonitrile, together with a binder, a dispersant, a pigment and other additives, to form a paint liquid, and the paint liquid is coated on a sheeted supporter, e.g., paper, etc., and dried to obtain a coloring sheet for pressure-sensitive recording purpose. |
