Fecha de publicación: 29/08/1993 Fuente: WIPO "olive table" A thermal recording shell having a thermal color developing layer containing a color developer and a colorless or pale colored basic chromogenic dye, which further contains a stabilizer of Formula (I) and a sensitizer of Formula (II) or Formula (III), thereby obtaining a high sensitivity and improved image stability: Formula (I) (see fig. I) wherein A indicates (see fig. II) or (see fig. III) R1 and R2 individually indicate hydrogen or methyl; .alpha. is 0 or an integer from 1 to 5; .beta. and .gamma. individually indicate an integer from 1 to 5; B indicates (see fig. IV), (see fig. V), (see fig. VI), (see fig. VII), (see fig. VIII) or C and D individually indicate chlorine, bromine, methyl, methoxy, or ethoxy; and m and n individually indicate 0, 1, or 2; Formula (II) Formula (III)