To obtain an new disazo pigment excellent in optical characteristics such as hue, clarity and coloring force and durability such as light resistance, solvent resistance, heat resistance and heat-resistant transfer property and dispersing with specific producing device, capable of inexpensively and readily producing and useful for printing ink, coating, etc.
This compound is represented by formula I {A is a residue of a ketomethylene compound capable of carrying out enolation, e.g. a group of formula II [R1 is methyl or phenyl; R2 to R4 are each H, Cl, methyl, ethyl, methoxy, ethoxy, carbamoyl, a group of the formula COO- (Mn+/n) [M is H, n-valent metal; (n) is 2 or 3], a group of the formula SO3 (Mn+/n), etc.]}, e.g. 1,3-bis(4-{[1-(phenylcarbazamoyl)-acetonyl]azo}phenoxy)benzene. The compound of formula I is obtained by converting a compound of formula III to a tetrazo compound, subjecting the tetrazo compound to coupling reaction with a ketomethylene compound capable of carrying out enolation and as necessary, further carrying out after-treatment of the reaction product.
SUDA YASUMASA
ENDO ATSUSHI
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