| 摘要 |
PURPOSE:To improve a coloring speed and ensity, by a method wherein acids are fed as coloring auxiliaries on a recording sheet in which a layer, containing an electron-giving coloring agent and a salicylin acid derivative sodium salt, is placed. CONSTITUTION:After the electron-giving coloring agent (for example; crystal violet lactone and the like) is mixed with a resin binder (for example; polyvinyl alcohol water solution and the like), the salicylic acid derivative sodium salt and postassium salt, represented by a formula (where R is C1-5 radical; n is 1 and 2), are added to the mixture. Said addition is applied on a paper support matter for drying to obtain the recording sheet. An organic acid (for example; malein acid and the like), an inorganic acid (for example; phosphric acid and the like), or a coloring agent, such as a metal halide and the like, are injected in a picture shape by the use of a nozzle and the like to obtain an explicit coloring picture. |
