| 摘要 |
PROBLEM TO BE SOLVED: To prevent an edging by another color from occurring by using a material which shows the mutual difference in the development temperatures of thermal developing components whose developed color tones vary and that the higher developing temperature of the thermal coloring composition, the shorter heating time required for the development and only by a method for controlling a heating energy. SOLUTION: When a thermal color developing composition contains two or more different types of color developing component, the developing component is spaced with a color developing adjustment layer. This layer curbs the mixing and chemical reaction of the color developing component at the time of heating for printing and thereby regulates a color developing temperature and/or a heating time required for the color development. This method enables the saving of heating time to the advantage of the thermal color developing composition whose developing temperature is higher. Consequently, for example, when the thermal color developing composition whose developing temperature is high is caused to develop a color at a high heating temperature in a short heating time, the thermal color developing composition whose developing temperature is lower does not develop a color at all, as this composition is not given enough time required for the composition whose developing temperature is lower to develop the color. |
