Alkali-clearable phthalimide-based azo disperse dyes and preparing method thereof and dyeing method thereby

摘要

PURPOSE: Provided are an azo-based alkali-clearable disperse dye having a phthalimide structure, which has clearing ability under a weak alkali condition after dyeing polyester fiber material, and a method for dyeing the polyester fiber material by using the azo-based alkali-clearable dispersing dye. CONSTITUTION: The azo-based alkali-clearable disperse dye having the phthalimide structure is an azobenzene-based monoazo compound(formula I) and is produced by coupling-reacting a diazonium salt(formula II) of an aromatic amine compound with an aromatic aniline compound(formula III) as a coupling component. And the method for dyeing the polyester fiber material uses the azo-based alkali-clearable disperse dye(formula I) and contains an alkali clearing process using a weak alkali solution instead of a reduction clearing process using a strong alkali and a reducing agent, wherein pH of the weak alkali is 11-12. In the formula, X is hydrogen, methyl, or ethyl, Y1 and Y2 are hydrogen, methyl, methoxy, or acetylamino, and R1 and R2 are substituted or unsubstituted alkyl.