| 摘要 |
A magenta pyrazolone dye of formula <FORM:1091366/C4-C5/1> is disclosed wherein R1 is an acid solubilizing group, e.g. carboxylic or sulphonic acid groups, and R2 is alkyl of up to 4 C atoms. The dye is prepared by suspending the 4-amino pyrazolone in water, making alkaline with K2CO3, oxidizing by passing air therethrough for 6-7 hours, and precipatating the dye by adding CH2COOK. |
