نشریه علوم و فناوری رنگ
سال سوم شماره 3 (پیاپی 9، پاییز 1388)

In this paper, the influence of various factors on the quality of automotive coating appearance (NAP No., tension value, etc) such as coating layers, surface position, process conditions and film thickness were studied. Six-sigma method was employedto investigate and analyze the effect of the above mentioned factors. Via six-sigma methodology, the quality of factors was improved which in turn leads to improve the sigma level from 0.4 to 1.8 as well as increasing the quality of the product. Finally, the films thickness, flash off time, application temperature, grade of sanding and surface position were optimized. J. Color Sci. Tech. 3(2009), 65-72.© Institute for Color Science and Technology.

The purpose of this research was to examine the influences of proteases treatment on wool fabric in acidic media. To this ends, woolen fabric samples were treated with proteases (EC 3.4.21.62) at 50-60ºC, pH=5 for 60 min.. Different properties of the treated fabric samples such as: weight loss, tensile strength, felting, alkali solubility, water absorption time, madder dye absorption, pilling, abrasion and bending length were investigated and reported. The results showed that treatment of wool fabric in acidic media has no or little influence on the tensile strength of the wool fabric while the same treatment in alkali media has significant influence on tensile strength. The wool sample treated with 10% protease in acidic media indicated the similar tensile strength as untreated fabric. However, higher protease concentrations reduce the tensile strength and fabric weight. The results also showed that the wool fabric samples treated with proteases in mild acidic media have higher water absorption, higher dye madder absorption, less pilling, less wet shrinkage, improvement of water absorption time and higher whiteness. J. Color Sci. Tech. 3(2009), 73-80.© Institute for Color Science and Technology.

In this paper, the use of Tamarind hull biosorbent (Tamarindus indica) has been investigated to remove the cationic dye from textile effluent. Basic Blue 41 (BB41) was used as cationic dye model. The surface characteristics of Tamarind hull were investigated using Fourier transform infra-red and Scanning electron microscope. The influence of process variables such as adsorbent dosage, initial dye concentration and pH were studied. Data evaluated for compliance with the Langmuir, and Freundlich isotherm models. The presence of functional groups such as hydroxyl and carbonyl groups onto Tamarind hull surface were proved by FTIR analysis. The results indicate that the data for adsorption of BB41 onto Tamarind hull fitted well with Langmuir isotherm. Also, adsorption kinetics of BB41 on biosorbent was studied. The rates of sorption were found to conform to pseudo-second order kinetics with good correlation. Results indicate that Tamarind hull could be used as a biosorbent to remove the cationic dyes from contaminated watercourses. J. Color Sci. Tech. 3(2009),81-88.© Institute for Color Science and Technology.

Polyurethane-clay nanocomposites were prepared by applying high-intensity ultrasound during the synthesis of clay-urethane nanocomposites. In this article, rheological measurements along with turbidimetry, optical microscopy, X ray diffraction (XRD)and Transmission electron microscope (TEM) analyses were carried out. The results of XRD showed that the distances between silicate layers of clay reached to 41 A0 in the polymeric matrix. Results showed that nanocomposites had higher dynamic moduli, and solid like behavior in comparison to that of neat polyurethane. The strong increase in modulus of nanocomposites was due to the intercalated and dispersed silicate platelets. The increase rate in storage modulus of these composites decreased at higher organoclay loadings and was not linear. Also, the sample that contained 5% organic clay showed a shear thinning behavior at low frequencies. By using the results of XRD, optical microscopy and rheometery analysis, the state of dispersion and optimum percent of clay that has the best dispersion state were obtained. J. Color Sci. Tech. 3(2009), 89-96.© Institute for Color Science and Technology.

In this research the efficiency of electrochemical treatment process with iron electrodes for treatment of a colored wastewater containing Reactive Red 198 in laboratory scale was studied. The effect of operating parameters such as voltage, reaction time, electrolyte concentration, initial dye concentration and interelectrode distance on the dye removal efficiency have been investigated. The experiments were carried out in a plexiglass reactor. The results indicated that electrochemical process is veryefficient mothod for dye removal and in the operational condition able to remove color and COD as high as 99% and 66.6% respectively in 30 minutes at 40 volts and 1 cm interelectrode distance. This study revealed that when the voltage and reaction time increased and interelectrode distance decreased, energy consumption, final pH and dye removal, would be increased. Increasing electrolyte concentration, resulted in decreasing retention time for dye removal. J. Color Sci. Tech. 3(2009), 97- 105.© Institute for Color Science and Technology.

Design of radiation paint cure ovens in automotive industries is an important yet difficult task which has not been discussed adequately in the open literature. This is particularly true when complex body frames are considered. In this paper a numerical dynamic optimization algorithm is proposed which provides the optimum temperatures of a fixed number of radiation panels installed on the ceiling of an automotive paint cure oven. Using a paint cure window criterion to define the admissible design space and the objective function, a nearly uniform and satisfactory paint curing condition is obtained at the optimum design point. To describe the method in a simple, clear and computationally affordable context, a two-dimensional section of an oven and the automobile body is considered. It is shown that even the classical steepest descent optimization method converges fast enough in this particular application. The proposed method is also applicable in three-dimensional problems. J. Color Sci. Tech. 3(2009), 107-119.© Institute for Color Science and Technology.

In this study, Anatase TiO2 sol was synthesized under mild condition (80oC and ambient pressure) by hydrolysis of titanium-nbutoxide in acidic aqueous condition and subsequent reflux. Crystalline TiO2 sol was deposited on soda lime glass by spin coating method in ambient condition. Crystalline structure, particle size and morphology of deposited films were investigated by X-ray diffraction pattern, transmission electron microscopy (TEM) and scanning electron microscopy (SEM), respectively. Results are indicative of anatase crystalline TiO2 with mean particle size of 30-40 nm which are uniformly distributed on thesurface. Photocatalytic activities of prepared films were systematically investigated by degradation of methylene blue (MB) and the results were compared with coatings which are prepared from commercial sol as well as heat treated sample at 650 oC. J. Color Sci. Tech. 3(2009), 121-129.© Institute for Color Science and Technology.