NOPR Collection:

Syntheses and dyeing performance of azo disperse dyes based on schiff's base system

1996-09-01T00:00:00Z

Title: Syntheses and dyeing performance of azo disperse dyes based on schiff's base system Authors: Vashi, H J; Desai, K R Abstract: Ten azo disperse dyes, 2-(6'-hydroxyschiff's base-5'arylazo-1’-yl)-5-nitrobenzothiazoles, were synthesized and their dyeing performance on polyester fibre assessed. All the compounds were characterized by spectral and elemental analyses. The compounds, when applied on polyester fibres, gave good to very good light fastness, good to excellent fastness to washing, rubbing and perspiration, and very good to excellent exhaustion. Page(s): 225-227

Chemical resistance and tensile properties of epoxy-coated bamboo fibres

1996-09-01T00:00:00Z

Title: Chemical resistance and tensile properties of epoxy-coated bamboo fibres Authors: Rajulu, A Varada; Reddy, G Ramachandra; Chary, K Narasimha Abstract: The chemical resistance and tensile load at break of bamboo fibres (Dendrocalamus striclus) before and after coating with a high performance epoxy resin (Araldite LY 5052/Hardner 5052 system) have been studied. It is observed that the tensile load at break and chemical resistance of bamboo fibres increase on coating, indicating that epoxy resin and bamboo fibres are favourable materials for making the composites. Page(s): 223-224

Ambient temperature bleaching of jute fibre - Its effect on yarn properties and dyeing behaviour

1996-09-01T00:00:00Z

Title: Ambient temperature bleaching of jute fibre - Its effect on yarn properties and dyeing behaviour Authors: Basu, G; Chattopadhyay, S N Abstract: The effect of ambient temperature bleaching of jute fibre with hydrogen peroxide on yarn properties and dyeing behaviour has been studied and compared with that produced by conventional hot bleaching technique. The optimum duration for ambient temperature bleaching of jute fibres of both white and tossa varieties has been found to be 1.5 h. Spinning process causes around 30% loss in whiteness index of bleached fibre, and carding and spinning stages are mainly responsible for it. Yarns produced from both hot and ambient temperature bleached fibres using suitable bleaching recipes give remarkably higher tenacity and higher work of rupture than that of grey yarn. Dyeing of yarn made from ambient temperature bleached fibres results in higher dye uptake and shows an upward trend in work of rupture. A suitable recipe for ambient temperature bleaching consisting of 50 gpl hydrogen peroxide, 15 gpl sodium hydroxide, 20 gpl sodium silicate and 2.5 gpl sodium persulphate is suggested to get better yarn property and dyeing behaviour. Page(s): 217-222

Upgradation of jute fibre by post-retting chemical treatment at never-dried stage

1996-09-01T00:00:00Z

Title: Upgradation of jute fibre by post-retting chemical treatment at never-dried stage Authors: Sarkar, A K; Saha, M; Chakraborty, S K; Adhikari, D; Basak, R K; Das, N N Abstract: A simple procedure for upgradation of jute fibre involving the application of some inexpensive chemicals, like diammonium phosphate (DAP), molasses and a non-ionic surfactant, at post-retting stage has been described. The chemicals were applied to the normal fibres as well as to those whose root ends had been discarded at pre-reuing and post-retting stages. Gradation of the fibres by commercial graders showed that discarding of the root ends at pre-retting stage improves the fibre quality by one grade (TD₆ to TD₅). Application of chemicals effected further improvement in 70% of pre-cut fibres by two grades (TD₅ to TD₃). Similarly, 70% of the normal fibres showed improvement by two grades (TD₆ to TD₄). Rejection of roots at post-reuing stage degraded the fibre quality. In general, DAP-treated fibres showed remarkable improvement in colour but best results were obtained with DAP-molasses-surfactant combination. Chemical analyses of the control and chemically-treated fibres showed that the added chemicals serve as nutrients for the growth of residual microorganisms left on retted fibres which induce a secondary retting in the drying stage. Page(s): 210-216