| 摘要 |
PURPOSE:To provide a thermal recording material having high sensitivity, less susceptible to deterioration of images with time and enhanced in reliability, by using a specified compound as a color developer. CONSTITUTION:At least one compound of formula (I), wherein each of R1, R2, R3 and R4 is a 1-22C alkyl, aryl or aralkyl, X is a halogen or lower alkyl, (n) is an integer of 1-3 and (m) is an integer of 0-3, is used as a color developer, in a thermal recording material utilizing a color forming reaction between a leuco dye and the color developer. As a result, there is an extremely low possibility of fading of recorded images with time or fading due to temperature or humidity. The compound of formula (I) may be, for example, an arbitrary combination of a carboxylic acid residue moiety with a primary ammonium moiety. |
