Novel chromogenic mono(indolylethylenyl)phthalides are of the formula
wherein A is a moiety of the type
L is an indole moiety; and
B is a moiety of the type
The compounds are prepared by condensing indolylethylene with a keto acid or its derivative and an electron acceptor in an organic solvent, and are useful in pressure-sensitive and thermal recording systems, particularly those which can be read by a machine capable of reading in the wavelength range 400 to 900 nm.
新颖的发色性单(
吲哚乙烯基)
邻苯二甲酸酯的结构式为
其中 A 是以下类型的分子
L 是一个
吲哚分子;以及
B 是以下类型的分子
这些化合物是通过在有机溶剂中将
吲哚乙烯与
酮酸或其衍
生物和电子受体缩合而制备的,可用于压敏和热敏记录系统,特别是可由波长范围为 400 至 900 纳米的机器读取的系统。