Interaction between quaternary ammonium Gemini-type surfactant and copper phthalocyanine dye

The interaction between a quaternary ammonium Gemini-type surfactant(EB-CDAC) and C.I.Direct Blue 199 with copper phthalocyanine structure was investigated by conductivity testing,absorption spectroscopy and surface tension measurement.The formation of dye-surfactant ion pair complex in the mixed solution resulted in the change of dye absorption spectra and the red shift of maximum absorption wavelength.The change of the surface tension and conductivity was also observed.The critical micelle concentration(CMC) of the dye-surfactant mixture is higher than that of the pure surfactant solution,and the conductivity of the mixture increased at first and then decreased with increasing the concentration of the surfactant in the mixtures.