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One approach to improve the affinity of anionic dyes for cotton is to add cationic dye sites to the fibre. The dyeing behaviour of cotton that had been rendered cationic by reaction with 2,3‐epoxypropyltrimethylammonium chloride was examined. Dye yields and fastness properties are reported for a number of direct, reactive and acid dyes with the modified fibre. Excellent dye yields and colour fastness properties were obtained without the use of electrolytes, multiple rinsings or fixation agents which are normally employed in cotton dyeing.

Polypropylene and nylon 66 fabrics are subjected to atmospheric pressure He and He-O 2 plasmas for selected exposure time intervals. Scanning electron microscopy analysis of the fabrics shows no apparent changes in the plasma-treated nylon fiber surfaces, but significant surface morphological changes for the polypropylene. Surface analyses of the nylon filaments reveal small differences in the surface carbon and oxygen contents between the treated and control groups. The surface oxygen and nitrogen content of the polypropylene fabric increases significantly after treatment in both He and He-O 2 plasmas. There is a slight decrease in nylon fabric tensile strength after treatment in He plasma for 3 minutes, while. there is no significant change in tensile strength of the nylon fabric treated with He-O 2 after exposure times of up to 8 minutes.Plasma treatment of textile fabrics and yams is being investigated as an alternative to wet-chemical fabric treatment and pretreatment processes, e.g., shrink resistant (wool) or water-repellent finishing, which tend to alter fabric mechanical properties and are environmentally hazardous. Plasma treatment of textiles may result in desirable surface modifications, including but not limited to surface etching, surface activation. crosslinking, chain scission, decrystallization, and oxidation. Treatment depends on the choice of working gas and plasma density and energy [ 1,3,6,14,17,19]. The effects of low-pressure (vacuum) plasma treatments of polyester, high performance polymers, and wool are well documented [3, 11, 17, 191, while relatively little has been published about atmospheric pressure plasma treatments [4, 14, 171. Despite the effectiveness of plasma treatments on textiles, the inability to successfully incorporate low-pressure plasma treatment equipment into a continuous textile finishing operation has seriously limited the commercial viability of the technique [ 11 ]. Previously, plasmas generated at atmospheric pressure were believed to be neither uniform nor stable: however, recent research on atmospheric plasmas has shown their uniformity, stability, and applicability to processing and treatment of textiles, as well as many other materials [2]. In addition, atmospheric pressure plasma treatment devices can be integrated with continuous on-line processing of textile materials.While plasma treatment may result in many favorable or desirable surface modifications of textile materials. it may also cause undesirable physical degradation of the polymer surface [5,10,11 ]. Treatment parameters must be optimized in order to achieve desirable surface modifications without changing bulk properties. This paper presents results on polypropylene and nylon 66 fabrics treated with atmospheric plasmas of helium (He) and a mixture of helium and oxygen (He-02). Helium is typically used to initiate and generate the plasma at atmospheric pressure before another gas is introduced to the system. If there are no measurable changes in surface or mechanical properties as a result of e...

Methods are developed for imparting crease angle recovery performance to cellulosic fabrics based on durable ionic crosslinks. These methods, which avoid the formaldehyde release of conventional finishes, include treating cellulose with chloroacetic acid (or an other reactive anion) and cationized chitosan (or another polycation). Alternative methods include treating cellulose with 3-chloro-2-hydroxypropyl trimethyl ammonium chloride or another cationization reagent) and a polyanion, or with chloroacetic acid and 3-chloro- 2-hydroxypropyl trimethyl ammonium chloride. A method for producing highly cationic chitosan is also presented. Crease angle recovery and strength data are correlated to the amount of polyelectrolyte add-on.

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