Heat sensitive recording material, and color developer

A compound of formula (I)

• wherein
• R and R1 are independently selected from the group of
• linear or branched C1-C18-alkyl,
• R11O-R12— wherein R11 and R12 are independently linear or branched C1-C8-alkyl,
• (R13)2N—R12— wherein R13 is a linear or branched C1-C8-alkyl or together with the nitrogen to which they are attached form a 5 or 6 membered ring, and
• a radical of formula (II)
• wherein, R2, R3, R4, R5, and R6 are independently selected from the group of
• hydrogen,
• linear or branched C1-C8-alkyl,
• —NH—C(═O)—R14, —C(═O)—NH—R14, wherein R14 is linear or branched C1-C8-alkyl,
• —C(═O)OR15, wherein R15 is linear or branched C1-C8-alkyl, and
• halogen, or
• R2 and R3, or R4 and R5 or both, or
• R3 and R4, or R5 and R6 or both, or
• R2 and R3 as well as R5 and R6 together form a hydrocarbon diradical comprising 3 or 4 carbon atoms;
• and
• Q is a single bond or branched or unbranched C1-C8-alkylene, optionally comprising one or more oxygen atoms;
• with the proviso that at least one of R or R1 is a radical of formula (II).