水相介质中合成颜料棕25研究

Study on the Synthesis of Pigment Brown 25 in Water Suspension

在水相介质中,利用重氮化反应,研究了2,5-二氯苯胺与5-(2′-羟基-3′-萘甲酰胺基)-苯并咪唑-2-酮一步合成得到颜料棕25的制备工艺,并采用正交设计方案讨论了分散剂用量、反应温度和时间、介质的pH等因素对颜料着色力和色光的影响,得到的最佳工艺条件为:偶合过程中,分散剂的质量分数为2%(反应物总质量计),偶合介质的pH=6.5;颜料化过程中,温度为115℃,时间为15h。该方法是一种清洁生产技术。

A preparation process to synthesize pigment brown 25 in one-step from 2,5-dichloroaniline and n-(2,3-dihydro-2-oxo- 1H-benzimidazol-5-yl)-3-hydroxy-2-naphthalenecarboxamide by diazotization in water phase medium is studied. Influence of factors such as the dispersant quantity, reaction temperature, reaction time, and medium pH on the tinting and shade of pigment are discussed with orthogonal design method. Best processing conditions are: dispersant mass fractions is 2% (based on the total quantity of reaction materials), pH of coupling medium is 6.5 in the coupling reaction, temperature is 115 ℃ and time is 15 h during the pigmentation process. This method is a kind of clean production technology.