PURPOSE: To obtain a recording material suitable for the reading of OCR using a light source having a light emission wavelength in the region of 750-850nm by using a specified phthalide compound as the electron-donating leuco colorant.
CONSTITUTION: A recording material using a color reaction of an electron- donating leuco colorant with an electron-accepting color developer, wherein a phthalide compound of formula I (wherein R1 is 4-8C alkyl) is used as the electron-donating leuco dye, or alternatively a combination of the phthalide compound of formula I with a fluoran compound of formula II [wherein R1 is as defined above; R2 and R3 are each alkyl, alkoxyalkyl, cycloalkyl or (substituted) phenyl; R4 is H, alkyl, alkoxyl or Cl; and R5 and R6 are each H, alkyl, Cl, F or trifluoromethyl) is used as the electron-donating leuco dye. This material is suitable for the reading of OCR using a light source having a light emission wavelength in the region of 750-850nm.
NAKAO SATOSHI
HORIUCHI KENICHIRO
MATSUMOTO MANSUKE
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