To obtain an anthraquinone-based compound rich in color, having excellent color mixing properties, strongly coloring power, high stability and especially high solubility.
This compound is shown by formula I (R1 and R2 are each H, a 1-8C alkyl, a halogen, a 5-8C cycloalkyl or the like; R3 is a 1-8C alkyl, a halogen or the like) such as a compound of formula II. The compound of formula I is obtained by reacting (A) a compound of formula III with an amine of the formula R1HNR2 to give (B) an amidocarboxylic acid anthraquinone compound and esterifying the compound by using (D) an alkylating agent (e.g. methyl iodide or the like) under (C) a basic compound such as sodium hydroxide, etc., preferably at -50 to 200°C. The amount of the component C added is preferably 0.1-10 mols based on 1 mol of the component B. The compound of formula I is preferably added to a recording material such as an ink for sublimation transfer recording, an ink for dissolution type sublimation transfer recording, etc.
OKUMA TADASHI
OI TATSU
TAKUMA HIROSUKE
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