| abstract |
Color developer, thermosensitive recording material of formula (I) Ar 1 -SO 2 -NH-C 6 H 4 -SO 2 -C 6 H 4 -NH-CO-NH-Ar 2 (I), comprising A carrier substrate and a thermosensitive color-forming layer comprising at least one color former and at least one phenol-free color developer, wherein the at least one phenol-free color developer is a compound of formula (I), and preparation The method of this heat-sensitive recording material. |