Use of amorphous TiO2 deposited on cotton by sol-gel process for de-colorization of direct dye solutions in presence of UV radiation

In this investigation, decolorization of a direct dye solution catalysed by TiO2 coated on a cotton fabric by sol- gel route in presence of UV radiation has been studied. Effect of various process and material parameters like initial dye solution concentration, treatment time and temperature, stirring rate and construction of fabric on dye decolorization extent has been studied. It is observed that with a starting dye solution concentration of 0.1 g/L, almost 80% dye removal can be achieved. It is not possible to improve the decolorization extent beyond 80% by any combination of parameters. X-ray diffraction studies reveal that the form of TiO2 deposited on cotton fabric is not crystalline but amorphous in nature. While the UV radiation intensity and the fabric construction influence the dye decolorization, the treatment temperature and stirring rate do not have much bearing on decolorizing efficiency

Development of antibacterial knitted fabrics from polyester-silver nanocomposite fibres

419-425Development of durable antibacterial knitted polyester fabrics by incorporation of small proportion of polyester-silver nanocomposite fibres has been attempted in this research. Polyester-silver nanocomposite fibres are blended with normal polyester fibres at three weight fractions (10, 20 and 30%). Three parameters, namely blend proportion (wt.%) of nanocomposite fibres, yarn count and knitting machine gauge, have been varied for producing 27 knitted fabrics. Knitted fabrics prepared from polyester-silver nanocomposite fibres show good to excellent antibacterial activity (65-99%) against both S. aureus and E. coli bacteria. Blend proportion of nanocomposite fibres is found to be the most dominant factor in influencing the antibacterial activity of knitted fabrics. Antibacterial activity also increases with coarser yarn count and higher knitting machine gauge. It is also found that the tightness or compactness of knitted fabrics is correlated positively with their antibacterial activity

Development of antibacterial knitted fabrics from polyester-silver nanocomposite fibres

Development of durable antibacterial knitted polyester fabrics by incorporation of small proportion of polyester-silver nanocomposite fibres has been attempted in this research. Polyester-silver nanocomposite fibres are blended with normal polyester fibres at three weight fractions (10, 20 and 30%). Three parameters, namely blend proportion (wt.%) of nanocomposite fibres, yarn count and knitting machine gauge, have been varied for producing 27 knitted fabrics. Knitted fabrics prepared from polyester-silver nanocomposite fibres show good to excellent antibacterial activity (65-99%) against both S. aureus and E. coli bacteria. Blend proportion of nanocomposite fibres is found to be the most dominant factor in influencing the antibacterial activity of knitted fabrics. Antibacterial activity also increases with coarser yarn count and higher knitting machine gauge. It is also found that the tightness or compactness of knitted fabrics is correlated positively with their antibacterial activity.

Influence of Binder Type on Color Characteristics of Cotton Fabric Colored with a Photochromic Colorant

Photochromic colorants change rapidly and reversibly from colorless to colored state when activated by ultraviolet radiation. They can be applied on textile substrates with use of organic binders. Different type of binders and their concentration may have a significant effect on color development and other related properties. In this work, a study of the effect of binder type at different concentrations on the color development, wash fastness and some comfort characteristics is undertaken. It was found that while these properties vary with binder type and concentration, the best color development is obtained at an optimum concentration of 5% binder. The presence of binder may affect comfort related properties of the fabrics, such as stiffness, water absorbency, air permeability, sometimes quite adversely. Hence a careful selection of the binder type is needed depending on the most important requirement in the colored fabrics

Dyeing of polyester and wool with solvent-assisted color extract from ratanjot

400-404A series of homologous alcoholic solvents and their mixtures has been used for the extraction of coloring matter from ratanjot (Onosma echoides) powder. The extracted coloring matter is then used for dyeing of wool and polyester fabrics. The dyebaths are prepared based on aqueous, solvent and solvent assisted dyeing mediums. It is found that as compared to a single solvent, a mixture of solvents results in higher extraction of colorants from ratanjot. Also, the depth of shade reduces with increasing hydrophobicity of the dyeing medium using the same extraction medium. While the fastness to washing (change in color) is found to be good to excellent (3-5) on polyester, it is rather low (1-3) on wool. This can be attributed to the hydrophobic nature of colorants extracted from ratanjot, which resemble disperse dyes and have poor wash fastness on wool but show good wash fastness on polyester

Use of amorphous TiO₂ deposited on cotton by sol-gel process for de-colorization of direct dye solutions in presence of UV radiation

474-479In this investigation, decolorization of a direct dye solution catalysed by TiO2 coated on a cotton fabric by sol- gel route in presence of UV radiation has been studied. Effect of various process and material parameters like initial dye solution concentration, treatment time and temperature, stirring rate and construction of fabric on dye decolorization extent has been studied. It is observed that with a starting dye solution concentration of 0.1 g/L, almost 80% dye removal can be achieved. It is not possible to improve the decolorization extent beyond 80% by any combination of parameters. X-ray diffraction studies reveal that the form of TiO2 deposited on cotton fabric is not crystalline but amorphous in nature. While the UV radiation intensity and the fabric construction influence the dye decolorization, the treatment temperature and stirring rate do not have much bearing on decolorizing efficiency