| 摘要 |
PURPOSE:To improve image preservability, the whiteness degree of a recording layer and coloring properties by providing a recording layer containing a colorless or pale specific basic dye and a specific developer which develops color through chemical reaction with the dye, on a support. CONSTITUTION:The subject thermal recording medium consists of 3-di-n- benthylamino-6-methyl-7-phelaminofluoran as a basic dye and alpha-naphthoic acid and/or its zinc salt as a developer. An application liquid is prepared by dispersing the basic dye and the developer together or separately using a stirrer/crusher with the assistance of water as a dispersant. Thus the medium obtained is highly stable against a variety of solvents on the background and recorded image and is free from the discoloration and color fading of a recorded image if preserved under high-temperature, high-humidity environments and is capable of an enhanced whiteness degree and coloring density of the recording layer. |
