JOURNAL OF COLOR SCIENCE AND TECHNOLOGY
Year:2009 | Volume:3 | Issue:1|Papers Count:13

The effect of different types of nano silica (nano cristobalite, hydrophilic nano silica and hydrophobic nano silica) on some properties of two component polyurethane clear coat has been studied. Rheometric studies at low shear rates shows a shear thinning behavior in the clear coats containing nano cristobalite and hadrophylic nano silica. The haze value was acceptable for clear coat containing surface treated nano silica (hydrophobic). Nano indentation measurements show the hardness value has increased in presence of nano particles and the scratch depth has decreased.

A series of novel monoazo disperse dyes based on naphthalimide containing butyric acid have been applied on the wool fabric. The build up and dyeing properties of these dyes such as leveling property, wash, light, perspiration for alkaline and acidic conditions and rubbing fastnesses on wool fabrics were investigated. The results showed that the applied dyes are capable to produce red to bluish red hues on wool fabrics. Due to the presence of carboxylic acid and hydroxyl groups on the molecular structure of dye 4, it showed favorable and higher chroma with respect to other used dyes. Comparing the build up the dyes with commercial disperse red 60 and disperse red 73 revealed that they are superior to the commercial ones. Measurement of fastnesses properties of dyed samples indicated that they have good wash (4-5), rubbing (4-5), perspiration (4-5) and moderate light fastnesses.

The toxicity reduction of two commercially available dyestuffs, Reactive Black 5 and Disperse Orange 25, by means of ultraviolet radiation and ultrasonic irradiation using H2O2 was investigated with emphasis on the effect of various parameters on decolorization and degradation efficiency. The toxicity was also evaluated in acute toxicity studies using Daphnia magna. Results showed that both dyes were toxic to D. magna. The toxicity tests with D. magna showed lesser toxicity than parent form of both dyes after UV and US processes. However, UV process was more effective than US process in reducing dye toxicity. The toxicity level of dyes solution after US plus H2O2 and UV plus H2O2 processes were even higher than the toxicity level found for the dye solution without any color removal treatment, indicating that even with a removal of 100% of the dye RB5 from the aqueous solution, an expressive mortality of the D. magna occurred. One possible reason for this increase in toxicity could be due to the presence of H2O2 in the effluents.

The present research is an attempt to explore possible correlations between various factors defined by two distinct and well known standard personality test procedures. (i.e. the color pyramid test and the Cattell personality Questionnaire). To this end 100 middle class twelve year old boys were tested firstly by the color pyramid test entailing color arrangements pyramid form from which 24 interpretable factors were extracted. The same group of boys were asked to fill the well known 14-factor Cattell’s questionnaire having 142 questions to obtain the well established personality factors in psychology. Statistical parameters such as F (one factor regression), R² (squared coefficient of multiple correlation) and T (significant effects) were calculated. From such parameters the common co-variants factors were extracted in order verify whether it is possible to use the Cattell questionnaire as an alternative to the color pyramid test in order to evaluate deep personality factors.

In this paper, synthesis and anntimicrobial properties of a cationic dye were investigated. 4-Amino-N-propyl-1,8-naphthalimide was reacted with chloroacetylchloride followed by N,N-dimethyldodecylamine and a cationic dye was obtained. The product was purified by recrystalization and TLC methods. The chemical structure of the product was characterized by using FTIR, 1HNMR, 13CNMR and elemental analysis. Also, the spectrophotometric data of the synthesized dye was studied. The antimicrobial property of the dye was evaluated by using a minimum inhibitory concentration method (MIC). The product showed considerable antimicrobial effectiveness against either Gram-negative or Gram-positive bacteria in solution.

Mainly leather is dyed using anionic dyestuffs such as acid, direct and metal complex dyes, but the use of pigments is not common for leather dyeing. Dye penetration into the inner layers of the leather is a difficult task due to 3D infrastructure of leather. In the present study, an attempt has been made to improve the exhaustion of nano-pigment in dyeing leather by using ultrasound. Optimum dyeing conditions including reduced dyeing time is aimed. Taguchi method was employed for the design of experiments. CIELAB color coordinates reflectance values of dyed leathers were evaluated using a reflectance spectrophotometer. The K/S values of the samples were considered to be proportional to the absorption of nano-pigment into the leather. The optimum level of the effective parameters namely as: wetting time, type of swelling agent, ultrasonic bath time, and amount of pigment were evaluated and confirmed by complementary experiments.

Denim washing is one of the finishing processes with the great application due to creating special appearance and updating clothes. In current study, the effects of laccase is considered in different methods of washing including laccase alone, laccase along with acid cellulase and along with neutral cellulase. The color changes of different samples are compared by colorimetric indices for garment surface and back and also white pocket and also the effluents in the remaining baths of stonewashing were also monitored by spectrophotometer after each processing. The tensile and the weight changes of samples in different treatment are measured within the standard methods. The results show that co-application of laccase with cellulase increasing the lightness and decreasing the staining on both back of garment and white pocket. With increasing of laccase in mixture of enzymes back-staining was decreases. The result of spectrophotometer was recognized that laccase decomposes the removed indigo during stone washing.