| 摘要 |
PROBLEM TO BE SOLVED: To obtain an oil based ink composition which has a good hue and can form images having high storage stability such as lightfastness. SOLUTION: This oil based ink composition comprises an oil based medium and a compound represented by the formula (wherein Ar is an aryl group or a heterocyclic group; X, Y, and Z are each a group forming a unsaturated hetero 5-membered ring together with two carbon atoms and may have a substituent; R is NHRa or CH(Rb)(Rc); one of Rb and Rc is a substituent having a Hammett's substituent constant σρ of 0.3-1.5 and the other of Rb and Rc is a hydrogen atom, an aryl group, a heterocyclic group or a substituent having a Hamett's substituent constant σρ of 0.3-1.5). |
