A derivative of chito-oligosaccharide (COS), N-(2-hydroxyl)propyl-3-trimethyl ammonium chito-oligosaccharide chloride (HTACC), was synthesized using a reaction of glycidyltrimethylammonium chloride (GTMAC) and COS prepared by depolymerization of a fully deacetylated chitosan. COS and HTACC were applied to the cotton fabrics with a pad-dry-cure process using the reaction between the hydroxyl group of cellulose and terminal aldehyde group in COS and HTACC. Their minimum inhibition concentration (MIC) was evaluated, and the antimicrobial activity and durability to laundering of cotton fabrics treated with them were compared. The complete substitution of NH 2 groups in COS with GTMAC was obtained at a 4 : 1 mol ratio of GTMAC to NH 2 in 18 h at 80°C under the presence of acetic acid. MIC values of the 1.04 DS of HTACC and COS were 50 and 400 g/mL, respectively. A cotton fabric treated with 0.2% of HTACC and 1.8% of COS exhibited 100% reduction of bacteria. At the 50th laundering cycle, 0.3% of HTACC and 2.4% of COS indicated 100% bacterial reduction.

Cotton fabric with good antimicrobial activity and durability to washing is obtained by using chito-oligosaccharides without the need for a binding chemical as a crosslinker. The fully deacetylated chitosan is depolymerized into chito-oligosaccharide using sodium nitrite. The average degree of polymerization (DP) of chito-oligosaccharide is determined by colorimetric titration of a terminal aldehyde group of chito-oligosaccharide. In a pad-dry-cure process, two different chito-oligosaccharides (DP = 3 and 10) are applied to cotton fabric using the chemical reactivity of the terminal aldehyde group. The antimicrobial activity and durability to washing of the treated cotton are evaluated. The results show that at the fiftieth wash cycle, the cotton fabrics treated with 2.4% chito-oligosaccharide are able to maintain 95% (for a DP of 3) and 100% (for a DP of 10) bacterial reductions.The use of antimicrobial agents on textiles dates back to antiquity, when the ancient Egyptians used spices and herbs to preserve mummy wraps. In 1935, Domagk, a German scientist, developed an important class of antimicrobial agents based on quaternary ammonium salts.In the last few decades, the prevention of microbial attack on textiles and wearers of textile materials has become increasingly important to consumers and textile producers. The major classes of antimicrobial agents for textiles include organo-metallics, phenols, quaternary ammonium salts, and organo-silicones. These finishes should be durable, have selective activity towards undesirable organisms, be compatible with other finishes and dyes, and be nontoxic to humans [! 1].Chitin has a chemical structure similar to cellulose and is the second most plentiful natural polymer [6]. Currently, chitin is manufactured commercially own a large scale from the outer shells of crustaceans like shrimps and crabs, and is attracting a lot.of attention in agricultural, industrial, and medical fields [4]. Chitosan, a deacetylated derivative of chitin, is a natural, nontoxic, biodegradable polymer. Chitosan is also known as an antimicrobial polysaccharide due to the antimicrobial action of the amino group at the C-2 position of the glucosamine residue. °R ecently, Seo et al. used chitosan in the preparation of a blend fiber with antimicrobial properties [8]. There are some reports about the utility of chitosan polymer to impart antimicrobial activity in textile finishing. For example, chitosan salt produced by an organic acid was bound to the surface of textiles by a tremendous amount of resin, which formed crosslinks [3].Currently, little work has been published on using chito-oligosaccharide (cos) to produce antimicrobial activity in textile finishes. In this study, we prepare cos by depolymerizing chitosan and apply it to cotton fabric by a pad-dry-cure process. We then evaluate the antimicrobial activity of the treated fabric. ExperimentalA scoured and bleached 100% cotton fabric was used in this investigation. Chitosan with an initial 83.9% degree of deacetylation came from Kumho Chemi...

Five cationising agents were synthesised, through the reaction of various trialkylamines with epichlorohydrin, and then used for the cationisation of cellulosic fibre. The cationised cellulosic fibres could be dyed with acid dyes and showed excellent antimicrobial activity in spite of the low degree of cationisation.