Aqueous ink composition of reversible thermal discoloration and writing instrument using the same equipment and writing instruments

摘要

An aqueous ink composition for reversible thermal discoloration comprising water, a pigment microcapsule reversible thermal discoloration including a composition decoloracióntérmica comprising: (A) an organic dye compound electron donor, (B) an electron accepting compound and (C) a reaction medium which determines a temperature at which color reactions of amboscompuestos occur, a polymer flocculant, a polymeric dispersant comb having a carboxylic group in the side chain, a deazufre nitrogen compound and organic water-soluble resin, wherein the organic sulfur compound is a nitrogen compound selected from 2- (4-thiazoyl) -benzimidazole, 2- (tiocianatometiltio) -1,3-benzothiazole, 2-methyl-4 isothiazolin-3-one and 5-chloro-2-methyl-4-isothiazolin-3-one and in which, suchas polymeric flocculant soluble polymer is used in water selected from polyvinylpyrrolidone, oxide d and water soluble polyethylene ypolisacáridos and combinations thereof.