Browsing by Author "El-Gamal, A. R."

Now showing 1 - 4 of 4

Improving the Environmental Aspects of Sulphur Dyeing of Cotton Knitted Fabrics
(TAYLOR & FRANCIS INC., 2008) Ibrahim, N. A.; El-Gamal, A. R.; Mahrous, F.
An attempt has been made to search for an eco-friendly reductants and oxidants for complete substitution of the hazardous ones along with finding out proper conditions for attaining better knitted sulphur dyeings. The results detailed in this article indicate that a) the extent of coloration is governed by both the type of reductant as well as dye/reductant ratio, i.e. liquid glucose (LG, ratio 1/1) > glucose (G, ratio, 1/1) > molaas (M, ratio 1/4), as well as the knitted fabric structure i.e. Pique > Rib > Milton; (b) the depth of shade can be improved by raising the dyeing temperature up to 80 degrees C for 45 min., at a material-to-liquor ratio 1/10, in presence of 30g/l common salt; (c) the extent of sulphur dyeing is determined by the nature of oxidant, i.e. (NH(4))(2)S(2)O(8) > H(2)O(2) > None; (d) after treatment with cationic softener results in higher softness along with better washing and rubbing fastness; and (e) the dyeing as well as fastness properties of the obtained sulphur dyeings depend on the sulphur dye category.
Multifunctional Anionic Cotton Dyeings
(JOHN WILEY & SONS INC, 2010) Ibrhim, N. A.; Mahrous, F.; El-Gamal, A. R.; Gouda, M.; Husseiny, S. M.
Anionic cotton dyeings with anti-ultraviolet and antibacterial functions were prepared by the post-treatment of direct and reactive cotton dyeings with a zirconium oxychloride salt solution. The extent of improvement in the functional properties was governed by the structure and pretreatment history of the knitted cotton fabric, the kind and concentration of the anionic dye, and the dyeing regime. The chelation and fixation of the positively charged zirconium ions onto and/or within the dyed substrate resulted in an enhancement in the ultraviolet absorption capacity of the treated substrate and interaction with the thiol groups of the cellular protein; this imparted antibacterial activity against Gram-positive and Gram-negative bacteria without adverse effects on the hue of the obtained dyeings. Both the anti-ultraviolet and bacterial functions of the post-treated dyeings survived through 1.5 washing cycles. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 115: 3249-3255, 2010
A new approach for natural dyeing and functional finishing of cotton cellulose
(ELSEVIER SCI LTD, 2010) Ibrahim, N. A.; El-Gamal, A. R.; Gouda, M.; Mahrous, F.
A new approach for upgrading the dyeing properties of cotton knits with natural dyes as well as to enhance both the UV-protection and antimicrobial functions of the obtained dyeings was investigated. Factors affecting the dyeing and multifunctional properties of the treated substrates such as fabric structure, type and concentration of mordant, kind and percent of natural dye extract as well as dyeing regime were studied. In situ deposition of the mordant as a metal oxide onto and/or within the fabric structure followed by dyeing results in a dramatic improvement in the color strength as well as the fastness properties, in addition to an outstanding enhancement in both the UV-protection, against the harmful UV-radiation and the antibacterial activity against the hazardous G+ve and G-ve bacteria. The extent of improvement in the aforementioned properties follows the descending order: pre-mordanting followed by dyeing > dyeing only > none, and is determined by type and content of metal, physical state/chemical structure as well as extent of dye interaction and fixation, along with the fabric construction. The UV-protection properties as well as the antibacterial activities of the obtained dyeings are maintained even after 20 washing cycles. (C) 2010 Elsevier Ltd. All rights reserved.
UV-Protecting and Antibacterial Finishing of Cotton Knits
(JOHN WILEY & SONS INC, 2009) Ibrahim, N. A.; Gouda, M.; Husseiny, Sh. M.; El-Gamal, A. R.; Mahrous, F.
This article deals with enhancing the UV-protecting properties as well as the antibacterial activity of knitted cotton fabrics against two kinds of bacteria: gram-positive bacteria (G +ve), i.e., Staphylococcus aureus (S. aureus), and gram-negative bacteria (G -ve), i.e., Escherichia coli (E. coli). Results showed that the extent of improvement in the UPF values are determined by: the fabric structure, i.e., Interlock > Pique > Parasol, pretreatment history, i.e., gray > scoured > bleached, type of softening agent, incorporation of the UV-absorber in the softening bath as well as sequence of addition, in addition to the nature of the deposited metal-oxide, i.e., Cu > Zr > Zn > Al approximate to none. On the other hand, the antibacterial activities of the treated substrates against G +ve and G -ve bacteria are outstandingly improved by using the proper: fabric structure, i.e., Parasol > Interlock > Pique, state of the