C. W. M. Yuen

LOW TEMPERATURE PLASMA TREATMENT OF LINEN

Low temperature plasma treatments are applied to linen with oxygen and argon at various discharge power levels and exposure times. Their effects on bulk structure, surface morphology, flax fiber properties, and related fabric properties are investigated with a range of analytical methods. X-ray photoelectron spectroscopy reveals that the surface oxygen content of the plasma treated samples increases, which is supported by the results from fabric whiteness tests. Formation of voids and cracks on fiber surfaces is revealed by scanning electron microscopy. There is no significant change in x-ray crystallinity and cuprammonium fluidity, but there is a slight reduction in moisture regain for all plasma treated samples. Fabric weight loss increases with exposure time. Fabric water uptake and strength first increase and then decrease with prolonged exposure, whereas fabric bending rigidity, hysteresis, and wrinkle recovery improve slightly.

Wicking Properties of Linen Treated with Low Temperature Plasma

The wetting and wicking behavior of linen treated with low-temperature oxygen and argon plasma is presented. Wetting and wicking abilities of plasma treated linen are investigated using contact angles and upward and downward water wicking methods. The downward wicking method is more suitable for distinguishing the effects of plasma treatment under various conditions.

Chemical Silver Plating on Cotton and Polyester Fabrics and its Application on Fabric Design

Metallization is one of the finishing processes in textile treatment that can produce a unique fabric appearance. It appears to have great potential for application to garments for both functional and decorative effects. Chemical plating is an autocatalytic deposition method that can be used for precision work in conventional manufacture. This study has investigated the method for using chemical silver plating on cotton and polyester fabrics and the final properties of the metalized fabrics. The results showed that specific performance of the silver-plated fabric could be obtained if the optimum chemical plating condition was chosen. In addition, fabric design practice employing this chemical technique with the design method could achieve diverse effects.

Low Temperature Plasma on Wool Substrates: The Effect of the Nature of the Gas

Low temperature plasma (LTP) with three different nonpolymerizing gasses—oxy gen, nitrogen, and a 25% hydrogen/75% nitrogen gas mixture—are used to study the influence of the nature of each gas on the properties of wool substrates. The properties include fiber-to-fiber friction, feltability, fabric shrinkage, surface structure, dyeability, alkali solubility, and surface chemical composition. After the LTP treatment, those prop erties of the LTP-treated substrates change, and the changes depend on the nature of the plasma gas used. All the results are discussed quantitatively.

Determining Functional Groups of Commercially Available Ink-Jet Printing Reactive Dyes Using Infrared Spectroscopy

An infrared (IR) spectroscopic technique was used to determine the possible functional groups and chemical compounds present in commercially available ink-jet printing reactive dyes of four primary colours, i.e. Cyan, Magenta, Yellow, and Black. Although other instrumental analytical methods can help to determine the actual chemical composition of reactive dyes, the IR technique alone can still provide important structural information about the commercially available reactive dyes. Experimental results revealed that the reactive dyes under determination contained the same functional groups and chemical compounds as the reference reactive dyes.

USING NANO-TiO2 AS CO-CATALYST FOR IMPROVING WRINKLE-RESISTANCE OF COTTON FABRIC

In order to prevent cotton wrinkling, hydroxyl groups in the cellulose chain of cotton are partially crosslinked to keep the chain fixed relative to each other with dimethylol dihydroxy ethylene urea (DMDHEU). However, DMDHEU suffers disadvantages of reduced fabric strength and releasing of free formaldehyde. Recently, 1,2,3,4-butane tetracarboxylic acid (BTCA) has been explored as a new wrinkle-resistant agent providing similar performance to that of DMDHEU. In BTCA finishing, catalyst of inorganic phosphorus-containing acids was used but such phosphorus compounds have an adverse impact on the environment. In this paper, nano-TiO2 was used as a co-catalyst with sodium hypophophite in the treatment of cotton with BTCA, and the final properties were assessed.

The effect of the pretreatment print paste contents on colour yield of an ink-jet printed cotton fabric

Optimum condition concerning the content of pretreatment print paste and steaming time for ink-jet printing was newly developed through the orthogonal analysis. The cotton fabric treated under the newly developed optimum condition could achieve a high level of colour yield similar to that of the commercially pretreated cotton fabric available in the market for ink-jet printing. The results were discussed thoroughly in this paper.

Improvement of wrinkle-resistant treatment by nanotechnology

In this research, the non-formaldehyde wrinkle-resistant treatment of cotton fabrics has been investigated using the 1,2,3,4-butane tetracarboxylic acid as cross-linking agent and sodium dihydrogen hypophosphite as catalyst together with nano titanium dioxide as co-catalyst compound. The effect of changes in the concentration of 1,2,3,4-butane tetracarboxylic acid and nano titanium dioxide on the wrinkle recovery angle, tensile strength, tearing strength and bending length of cotton fabrics was evaluated. It was found that the addition of nano titanium dioxide could enhance the wrinkle resistance and decrease the bending length of the cotton fabric with little effect on the tearing and tensile strength of the treated fabrics.

Topographical Study of Low Temperature Plasma Treated Flax Fibers

A comprehensive study of morphological and topographical changes in low tempera ture plasma treated flax fibers is reported. Time-series images of fiber surface appearance are examined by environmental scanning electron microscopy (ESEM). As the exposure time increases, the depth of the micropores etched by the plasma increases with increasing pore width. The surface fibrils remain on the surface at up to 40 minutes of oxygen plasma or 60 minutes of argon plasma exposure. The dominant fabric weight loss of linen during plasma treatment is mainly attributed to fiber surface etching. Fiber contraction is also observed during plasma treatment. The ESEM micrographs show a good correlation with the SEM micrographs. The depth of the etched pits induced by the argon and oxygen plasma is measured by atomic force microscopy (AFM). On the relatively smooth surface of an untreated flax fiber, the argon plasma creates pits of mainly submicrometer size (both depth and diameter), while the oxygen plasma creates pits of a few micrometers. Image processing techniques provide a quantitative description of the surface topography of plasma treated flax fibers, and the FFT power spectra describe periodic surface features. Changes in the surface roughness of the plasma etched flax fibers are quantified by RMS values.

Effect of Low Temperature Plasma, Chlorination, and Polymer Treatments and Their Combinations on the Properties of Wool Fibers

In this study, wool fibers are treated with low temperature plasma, chlorination, polymer deposition, and their combinations. The treatments are classified into four categories for easy discussion. After the treatments, the surface properties in term of feltability, fiber damage, and dyeability are assessed and quantitatively discussed, and the relationships between the different properties are statistically assessed.