Crystal modifications of 2-m-toluidino-3-methyl-6-di-n-butylaminofluoran, process for preparing thereof, and recording materials containing said crystal modifications

摘要

The improved two types of crystal modification of 2-m-toluidino-3-methyl-6-di-n-butylaminofluoran, as well as the crystalline toluene adduct thereof have high solubility in inner-phase solvent(s). Recording materials that use those compounds as electron donating color formers exhibit particularly good performance in various characteristics such as whiteness of the background, its storage stability, color rendition, sensitivity for color formation and image storage stability.