NOPR Collection:

Chemical resistance and tensile properties of sisal fibres

Mon, 01 Jun 1998 00:00:00 GMT

Title: Chemical resistance and tensile properties of sisal fibres Authors: Padmavathi, T; Naidu, S Venkata Abstract: The chemical resistance and tensile load of sisal fibres (Agave varacruz) have been studied. It is observed that the fibres are more resistant to cone. HCI compared to other acids. The fibres treated with 18% solution of NaOH show more tensile load than the other chemically-modified fibres. Page(s): 128-129

Synthesis of azo disperse dyes with imidazolone moiety and their application on nylon arid polyester fibres

Mon, 01 Jun 1998 00:00:00 GMT

Title: Synthesis of azo disperse dyes with imidazolone moiety and their application on nylon arid polyester fibres Authors: Modi, B J; Bhalakia, S M; Patel, R G; Patel, V S Abstract: Twenty-two azo disperse dyes (Vla-k and VIIa-k) were prepared by coupling diazotized 1-(4aminophenyl)- 2-phenyl-4-(substituted Benzylidene)-5-imidazolones (III and IV) with various naphthol derivatives (Va-k) and their dyeing perfol1i1anceon nylon and polyester fibres has been assessed. All the imidazolone dyes showed fair to good fastness to light and very good to excellent fastness to washing, rubbing, perspiration and sublimation. Page(s): 123-127

Optimised chlorine-free bleaching systems for jute and jute/cotton blend fabrics

Mon, 01 Jun 1998 00:00:00 GMT

Title: Optimised chlorine-free bleaching systems for jute and jute/cotton blend fabrics Authors: Cai, Y; David, S K Abstract: A sequential two-stage bleaching process using peracetic acid followed by hydrogen peroxide. has been developed specifically for jute and jute/cotton blend fabrics. A peracetic acid system is optimised for jute by the selection of suitable buffering and stabilising agents. A superior bleaching effect is obtained by using TSPP as a stabiliser in the presence of a phosphate buffer, under mildly alkaline conditions (pH 8.0-8.5), whereby excellent fibre brightness may be achieved at temperatures as low as 40-60°C. A conventional H₂O₂-Na₂SiO₃ system has also been further optimised for jute by the exclusive use of sodium metasilicate at high concentrations of 3.5-4.0 g/l. Sequential bleaching with these independently optimised system results in an excellent degree of overall fabric brightness, such that the 1st-stage peracetic acid bleach may be carried out at relatively low temperature (30-40°C). This combination process therefore offers an effective, environmentally favourable and energy efficient option to conventional peroxide-utilising and chlorine bleaching processes. A further advantage is that it may also be successfully extended to the bleaching of jute/cotton blends. Furthermore, fabric tensile strength loss is less than that observed with high temperature H₂O₂-Na₂SiO₃ bleaching and the tendency towards photoyellowing of the combination bleached fabrics is not adversely affected, despite the high level of fabric brightness achieved. Page(s): 115-122

Studies in the right-first-time dyeing of cellulose with reactive dyes: Role of material-to-liquor ratio

Mon, 01 Jun 1998 00:00:00 GMT

Title: Studies in the right-first-time dyeing of cellulose with reactive dyes: Role of material-to-liquor ratio Authors: Nanda, B Abstract: The effect of variation in the material-to-liquor ratio on 37 commercially available reactive dyes (25 Procion and 12 Remazol) has been studied. It is observed that the extent of variation in the K/S value due to the variation in material-to-liquor ratio is different for different dyes. Based on the effect of variation in material-to-liquor ratio, the dyes have been classified into following three different groups: dyes which are marginally affected ; dyes which are moderately affected; and dyes which are significantly affected. The reproducibility of dyes which are marginally affected by the variation in material-to-liquor ratio is better than that of the dyes of other two groups. Page(s): 110-114