| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject new compound having magenta color with proper tincture of blue, having excellent light resistance, capable of giving color tone in wide visible region by using the magenta pigment with yellow and cyan ink and useful as a pigment, etc., for various ink compositions. SOLUTION: This sulfonic acid derivative of an anthrapyridone compound is represented by formula I (R1 ' is an alkoxycarbonyl, carboxylic or benzoyl; R2 is H or an alkyl; R3 and R4 are each H, a halogen, an alkyl or an alkoxy). The sulfonic acid derivative of the compound of formula I is obtained by reacting, e.g. a compound represented by formula II with a compound represented by the formula R1 '-CH2 -COOR5 (R5 is an alkyl) in the presence of sodium carbonate as a catalyst in a solvent such as ortho-dichlorobenzene at 100-200 deg.C for 3-30 hr to provide the compound of formula I and then sulfonating the compound in sulfuric acid containing fuming sulfuric acid. |
