Synthesis and Dyeing Properties of Alkali Soluble Disperse Dyes Derived from Terephthalic Acid(I) -Synthesis of Disperse Dyes Having Diester Groups-

테레프탈산을 이용한 알칼리 수용성 분산염료의 합성과 염색성에 관한 연구(I) -디에스테르기를 갖는 분산염료의 합성-

Diester type alkali soluble disperse dyes are characterized by the presence of a diester group in their chemical structure. The diester dyes are applied under normal exhaust dyeing condition. When the dyed polyester fabric is treated with water containing sodium carbonate at 70∼80$^{\circ}C$, diester groups in the unfixed dye are hydrolyzed to sodium carboxylate and the unfixed dyes are easily removed from the fiber. The aim of this study is the synthesis of novel alkali soluble azo disperse dyes containing diester group in the aromatic ring of diazo components. Terephthalic acid derivatives such as 2-amino-dimethyl terephthalate and 2-amino-3,5-dibromo-dimethyl terephthalate were synthesized and used as diazo components and coupled with four different coupling components which are generally used. The cyano groups could be introduced into azo disperse dye by substituting the bromo group using $Cu(CN)_{2}$ and NaCN. The chemical structures of synthesized intermediates and dyes were analyzed by IR and NMR spectroscopy. The wavelengths of maximum absorption of the synthesized dyes were in the range of 421∼602 nm.