NOPR Collection:

Improvement in properties of jute fibre by treatment with polysaccharide-degrading enzymes

2016-07-20T05:30:31Z

Title: Improvement in properties of jute fibre by treatment with polysaccharide-degrading enzymes Authors: Kundu, A B; Ghosh, B S; Chakrabarti, S K; Ghosh, B L Abstract: A simple method for wet-treatment of jute by a proprietary enzyme preparation having polysaccharide-degrading activities has been described. The action of enzymes reduces. the coarseness and rigidity of fibres and renders them distinctly softer. Page(s): 101-103

Synthesis of 2-methyl-6-(aryl/hetaryl-azo)thiazolo[4,5- b]quinoxalines and 7-( aryl-/hetaryl-azo)[ 1,4 ]dioxino[ 2,3-b]quinoxalines and their dyeing performance on polyester fibres

2016-07-20T05:42:09Z

Title: Synthesis of 2-methyl-6-(aryl/hetaryl-azo)thiazolo[4,5- b]quinoxalines and 7-( aryl-/hetaryl-azo)[ 1,4 ]dioxino[ 2,3-b]quinoxalines and their dyeing performance on polyester fibres Authors: Rangnekar, D W; Sabnis, R W Abstract: 6-Amino-2 -methylthiazolo[4,5-b ]quinoxaline (lVa) and 7- amino[1 ,4] dioxino[2,3-b] quinoxaline (lVb), obtained by the cyclocondensation of 2,3-dichloro-6-nitroquinoxaline (I) with thioacetamide (IIa) and 1,2-ethanediol (IIb) respectively and subsequent reduction of resulting nitroderivatives (III), were diazotized and coupled with suitable hydroxy heterocyclic couplers (VIa-d) and N,N-dialkyl substituted arylamines (VIe-g) to give 2-methyl-6-(aryl-/hetaryl-azo)thiazolo[4,5-b]quinoxalines (VIIa-g) and 7-(aryl-/hetaryl-azo) [1,4]dioxino[2,3-b]quinoxalines (VIIIa-g) respectively. The compounds VIIa-g and VIIIa-g when applied on polyester fibres as disperse dyes gave yellow to red violet shades with good pick-up, moderate to very good light fastness and good to excellent sublimation fastness. Page(s): 97-100

Action of surfactants on the levelling behaviour of dyeing of wool with reactive dyes

2016-07-20T05:40:56Z

Title: Action of surfactants on the levelling behaviour of dyeing of wool with reactive dyes Authors: Karmakar, S R; Shah, S M Abstract: The interaction of mono- and dichlorotriazine dyes (reactive dyes) with surfactants of different ionic nature in aqueous solutions has been studied spectrophotometrically. A definite change in the absorption maxima is interpreted in terms of compound formation. The extent of shift of λ_maxdepends not only on the ionic nature of the surfactants but also on the number of chlorine atoms present in the reactive system of dyes. The amount of surfactant required to shift the absorption maxima is generally less at higher pH values. The addition of surfactant in the dye bath appreciably decreases the percentage hydrolysis of reactive dyes and the maximum exhaustion and fixation take place at pH 4.7. From the sorption behaviour of reactive dyes on wool in presence and absence of surfactants, a possible mechanism of interaction in the dyeing process is discussed from the practical dyeing point of view to produce retarding and levelling effects. Page(s): 91-96

Effect of aftertreatments on direct dyed jute fabrics

2016-07-20T05:39:51Z

Title: Effect of aftertreatments on direct dyed jute fabrics Authors: Pandey, S N; Day, A; Chattopadhyay, S N; Pan, N C; Mathew, M D Abstract: The effect of aftertreatments with copper sulphate-potassium dichromate and two dye-fixing agents, viz. Lyofix 2776 and Sandofix WEI liquid, on direct dyed jute fabrics has been studied. It is observed that copper sulphate-potassium dichromate treated fabrics show improved light fastness whereas dye-fixing agent treated fabrics show improved colour strength. Page(s): 87-90