MANUFACTURE OF AGGREGATED PARTICLE FOR THERMAL RECORDING

摘要

PURPOSE:To provide a method of producing aggregated particles for thermal recording, which are excellent in thermal responding characteristics and image shelf stability. CONSTITUTION:Aggregated particles for thermal recording consist of five ingredients of a dye precursor comprising fluoran dyes, a color developer comprising specific derivatives of salicylic acid or metal salts thereof, an aromatic isocyanate compound, an imino compound developing a color by a reaction with an isocyanate compound under heating and having at least one >C=NH and a sensitizer as the essential ingredients. The aggregated particles for thermal recording are produced by a method wherein the aggregated particles comprising the five ingredients are formed by carrying out monodispersions or codispersions of the five ingredients to have mean particle sizes of 0.1 to 0.5mum with the aid of an anionic dispersant and mixing them together before adding a cationic dispersant thereto under stirring.