JOURNAL OF COLOR SCIENCE AND TECHNOLOGY
Year:2010 | Volume:4 | Issue:1|Papers Count:10

Anticorrosive property of a gemini cationic surfactant (12-4-12) and its monomeric counterpart, dodecyl trimethyl ammonium bromide (DTAB), on mild steel in 1M hydrochloric acid solution was investigated by electrochemical impedance spectroscopy (EIS). The results revealed the corrosion inhibition effect of these two surfactants on mild steel in acidic solution. It was observed that by increasing the immersion time in test solutions, corrosion resistance of mild steel increased, reaching a constant value after 2 h and 4 h immersions for 12-4-12 and DTAB, respectively. The monomeric surfactant, DTAB, had better corrosion inhibition effect compared to 12-4-12. The lower performance of 12-4-12 could be related to steric hindrance of the free head group.

In recent years hybrid pigments based on mica and an organic pigment have been prepared and used in different applications. In this paper, preparation of a colored mica was investigated and the samples were characterized by ultraviolet visible spectroscopy, optical and electronic microscopes. Results showed that the dye-uptake (%) on the mica surface varied from 10 to 80 percent depending on pH. Maximum dye-uptake was observed for pH 5-6. L*, a*, b*, h and C* values from colorimetric investigation demonstrated that colored mica samples of yellow, blue, gray and purple were prepared. It was shown that by this method not only the primary colors but also the secondary colors can be prepared.

The present study was carried out to investigate the effect of chitosan on the removal of Direct Yellow 9 and Reactive Orange 122 from contaminated water in comparison to activated carbon using batch adsorption studies. Chitosan has been selected as an adsorbent because of advantages such as high adsorption capacity, potential of variety of pollutants removal, non toxicity, availability, low cost and high rate of adsorption. Also the effect of contact time, initial dye concentration, adsorbent dosage, temperature and pH were examined and then removal efficiency of chitosan as compared to activated carbon was investigated. The results showed that removal of dyes increased by increasing contact time, adsorbent dosage, temperature and dye initial concentration decreasing. Also it may be concluded that chitosan was more effective than activated carbon.

In this study, a hyperbranched dendritic additive was used to improve the dyeability of a fibre grade PET. Various samples were prepared in an internal mixer at different concentrations of this additive. DSC was used to study the thermal behavior of the resultant compounded samples. It was shown that Tg of samples decreased as the concentrations of the additive increased. This difference in Tg between the neat PET and the compounded samples composed of 3 wt% hyperbranched was about 11°C. Sheet films were prepared and were subsequently dyed using C.I. Disperse Yellow 114 in presence and absence of a carrier. K/S, the dye uptake parameter increased from 1.2 to 3.0 as the concentration of additive increase for samples dyed in the absence of a carrier. The results showed that the need for use of a toxic carrier can be eliminated by this procedure.

One of the great concerns in the study of organic thin film photoreceptors is to enhance the efficiency of thin film photoreceptors. This efficiency is to a great degree, affected by pigment grain size dispersed in charge generation layer. In the first part of the project the average crystallite domain size and the root-mean-square strain of non milled sample of copper phthalocyanine and samples milled for 90, 180, 270 minutes have been determined using X-ray diffraction data and variance method. These samples were used as charge generation layers in the organic photoreceptors and their performances were evaluated. In the second part, copper phthalocyanine pigments were milled for 15, 30, 60, 90, 180, 270, 360, 600 minutes and their microstructures were studied as a function of milling time. Then the optimum grain size of pigments (in organic photoreceptors) were investigated.

Artificial intelligence is an advanced technology which is recently taking into account by researchers. In fact, Artificial intelligence is a method that provides required base to do intelligent processes by computer. A branch of artificial intelligence is Expert systems. These systems are computer tools that imitate knowledge and inference procedures of human experts to solve problems related to a specialized domain, so they consult at the level of a human expert and necessarily decide. The aim of this paper is to review Expert systems and some recent applications of it in various areas of coloration and textile industry.

The solubilization of a monoazo disperses dye based on naphthalimide containing an ester group in the presence of DTAB and two gemini cationic surfactants was investigated. The results showed that the solubilization power of gemini surfactants micelles was greater than that of conventional surfactant micelles (DTAB) for this dye. The nature of the visible absorption spectra in aqueous surfactant solutions above CMC was very similar to those in the ethanol solution. The solubilization power is strongly dependent on the surfactant structure and nature of micelles. The absorption of used disperse dye into polyester fabrics in the presence of cationic surfactants increased in the order of DTAB>12-4-12>14-414, once again confirming the higher solubilization power for gemini surfactants even at elevated temperatures.