42783-06-2Relevant academic research and scientific papers
Preparation method of ester group-containing azo disperse dye
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Paragraph 0046; 0047; 0048; 0049, (2016/10/10)
The invention discloses a preparation method of an ester group-containing azo disperse dye. The method comprises the following steps: carrying out a coupling reaction on a diazo salt and a coupling component, adding an alkali to the above obtained azo compound material system after the coupling reaction is completed in order to adjust the pH value of the system to 5-7, carrying out heating crystal transformation, and post-processing to obtain a dye filter cake. The pH value of the system is adjusted to 5-7 after the coupling reaction and before the crystal transformation, so hydrolysis of ester groups in the dye product is avoided, the yield of the dye product is improved, and the content of organic matters in wastewater is reduced, thereby the wastewater post-treatment difficulty is reduced.
