NOPR Collection:

Synthesis and dyeing performance of new bifunctional reactive azo dyes derived from 2-chloro-4-[4'-(β-sulphatoethyl)-sulphonyl- 2-methoxyanilino]- 6-(4"-hydroxy-1"-naphthyl)-s-triazine

2016-07-20T06:03:23Z

Title: Synthesis and dyeing performance of new bifunctional reactive azo dyes derived from 2-chloro-4-[4'-(β-sulphatoethyl)-sulphonyl- 2-methoxyanilino]- 6-(4"-hydroxy-1"-naphthyl)-s-triazine Authors: Dalal, M M; Rana, B J; Desai, K R Abstract: 2-chloro-4-[4'-(β sulphatoethyl)-sulphonyl-2-methoxyanilino]-6-(4"-hydroxy-1"-naphthyl)-s-triazine (V), obtained by treatment of 2,4-dichloro-6-(4'-hydroxy-1'-naphthyl)-s-triazine (III) with 4-(β- sulphatoethyl)-sulphonyl-o-anisidine (IV), was coupled with diazo solutions (VIIa-j) of various amino acids (VIa-j) to give 2-chloro-4- [4'-(β-sulphatoethyl)-sulphonyl-2-methoxyanilino]-6-(4"-hydroxy-3"- arylazo-1”-naphthyl)-s-triazines (VIIIa-j), Compound III was prepared by dissolving mixture of α-naphthol (I) and cyanuric chloride (II) in sodium-dried benzene. The compounds VIIIa-j, when applied on silk, wool and cotton fabric in 2% shade, gave moderate to good light fastness, good to excellent fastness to washing and rubbing and very good to excellent exhaustion. Page(s): 68-71

Studies on cooking of tussah silk cocoon

2016-07-20T06:01:56Z

Title: Studies on cooking of tussah silk cocoon Authors: Gulrajani, M L; Das, Subrata; Chattopadhyay, R; Sen, Kushal Abstract: An attempt bas been made to optimize the cooking conditions of tussah silk cocoon (Antheraea mylitta D.) with ethylenediamine using the Box and Behnken factorial design for three variables and three levels for each variable. It is observed that the duration and temperature of treatment as well as the concentration of ethylenediamine significantly influence the cocoon shell weight loss and silk filament recovery. Silk recovery improves with the shell weight loss of up to 11.5% after which no further improvement in silk recovery is observed. The mechanical properties of tussah silk filament have very little correlation with the process parameters. For better silk recovery, the following cooking conditions are recommended: ethylenediamine, 10% on the weight of cocoon; temperature, 80ᵒC; duration of treatment, 30 min; and meterial-to-liquor ratio, 1:30. Different races of tussah silk cocoon require adjustment in the duration of treatment. The hardness of water up to 1100 ppm has no significant effect on the recovery of silk in ethylenediamine cooking system. Page(s): 61-67

Reactive dyeing behaviour of ramie fabrics pretreated with different swelling agents and their rub fastness property

2016-07-20T06:00:59Z

Title: Reactive dyeing behaviour of ramie fabrics pretreated with different swelling agents and their rub fastness property Authors: Das, D; Samanta, A K; Dasgupta, P C Abstract: Scoured and bleached ramie fabrics were pretreated separately with four swe1lidg agents, viz. NaOH, EDTA, urea and phosphoric acid, and the consequent changes in tensile properties, extent of decrystallization, absorbency, dye uptake and fastness to washing light and rubbing for a monochlorotriazine reactive dye (C.I. Reactive Orange 13) were evaluated. Pretreatment with 20% urea or 20% NaOH under slack condition resulted in a more desirable balance in the above-mentioned properties including the improved dye uptake. Fastness to rubbing was poor and it was more pronounced at higher number of rub cycles. Both ring dyeing and higher coefficient of friction of ramie have been found to be responsible for this. To improve the rub fastness of reactive-dyed ramie fabric, post-treatment was carried out separately with catasoftener, silicone and polyethylene emulsion. Post-treatment with the last two finishing agents improved the rub fastness significantly on both NaOH (slack) and urea (slack) pretreated and reactive-dyed ramie fabrics. Page(s): 53-60

Influence of solvent pretreatment on dyeing performance of polyester yarns

2016-07-20T05:59:44Z

Title: Influence of solvent pretreatment on dyeing performance of polyester yarns Authors: Rajendran, S; Ramasamy, S S; Mishra, S P Abstract: The effect of trichloroacetic acid-methylene chloride (TCAMC) solvent system on the dyeability of three geometrically varying poly(ethylene terephthalate) yarns has been studied. The pretreatment was carried out at different concentrations of TCAMC for 5 min at about 30°C and the dyeability characteristics were studied making use of two different energy level commercial dyes at 115°C and 130°C. An enhanced dye uptake has been observed in all the cases studied. Increase in dye uptake depends on various factors besides the TCAMC concentration. The L, a, b colour coordinates were used to assess the change in colour, chroma, lightness and hue of the treated-dyed yarns. It has been observed that the treatment has greater effects on fibre morphology. The treatment leads to a high degree of swelling which facilitates easy penetration of dye molecules into the compact structure of the polymer. The unusual relationship between the increase in crystallinity and increase in dye uptake is explained. The overall fastness properties of the treated dyed yarns have been found to be good. Page(s): 44-52