NOPR Collection:

Dyeing parameters of hydroxynaphthoquinones extracted from Arnebia nobilis Rech.f

2016-07-20T05:49:34Z

Title: Dyeing parameters of hydroxynaphthoquinones extracted from Arnebia nobilis Rech.f Authors: Arora, Anjali; Rastogi, Deepali; Gupta, Deepti; Gulrajani, M L Abstract: Ratanjot (Arnebia nobilis Rech.f) has been used to extract dye for its application on various textile substrates such as cotton, wool, silk, nylon, polyester and acrylic. The sensitivity of the dye extract to pH and temperature is studied. The dye exhibits acute sensitivity to pH in terms of its solubility and colour. It is found to be thermally stable upto 80°C. The dyed polyester shows pink colour, nylon shows blue and all other substrates acquire a purple hue under similar dyeing conditions. This may be due to the reduction of dye from quinonoid form to benzenoid form in all the substrates except in polyester. The dye shows excellent wash, rub and perspiration fastness, however light fastness is found to be poor. Page(s): 91-97

Influence of UV radiations on the extraction and dyeing of cotton fabric with Curcuma longa L

2016-07-20T05:32:15Z

Title: Influence of UV radiations on the extraction and dyeing of cotton fabric with Curcuma longa L Authors: Adeel, Shahid; Bhatti, Ijaz A; Kausar, Afifah; Osman, Eman Abstract: The methanolic extract of irradiated Curcuma longa L powder has been prepared and used to study the dyeing conditions and characteristics of dyed cotton fabrics. The dyeing parameters such as time, material-to-liquid ratio and salt concentration have been optimized. To improve the colour fastness, pre- and post-mordanting has been carried out using copper , iron and alum mordants. The dyed samples are subjected to CIE Lab system using spectraflash SF-650 for the evaluation of colour strength and L*, a* and b* values. Finally, ISO standard methods are employed to study the colour fastness of dyed and mordanted fabrics. It is observed that the UV-radiation not only enhances the colour strength of dye on cotton fabric but also improves the colour fastness properties of irradiated cotton using methanol solubilized extracts of pre-irradiated Curcuma longa powder. Page(s): 87-90

Extraction of natural dye from Dahlia variabilis using ultrasound

2016-07-20T05:48:23Z

Title: Extraction of natural dye from Dahlia variabilis using ultrasound Authors: Mishra, Pradeep K; Singh, Pratibha; Gupta, Kamal K; Tiwari, Harish; Srivastava, Pradeep Abstract: Performance of ultrasound assisted extraction (UAE) technique for the extraction of colourant from Dahlia variabilis has been compared with conventional solvent extraction method. It is observed that UAE is more efficient process as compared to solvent extraction. The extracted dye is also characterized by FTIR and UV spectrophotometer. Change in colour with pH of extracted dye is observed due to bathochromic shift from blue green (pH 8.9) to deep red (pH 2.0). The extracted dye is also used for dyeing of wool yarns, generally used in the carpet industries. Good fastness properties of dyed yarn confirm its utility in the textile industries for eco-dyeing. The extracted dye also shows good potential to replace phenolphthalein as an indicator. Page(s): 83-86

Development of a quantitative assessment method for self cleaning by photocatalytic degradation of stains on cotton

2016-07-20T05:47:33Z

Title: Development of a quantitative assessment method for self cleaning by photocatalytic degradation of stains on cotton Authors: Sharma, Bhavana; Jassal, Manjeet; Agrawal, Ashwini K; Goyal, Nidhi; Rastogi, Deepali Abstract: This paper reports a standardised method termed as Stain Degradation Assessment (SDA) method, developed for the quantitative evaluation of self-cleaning efficiency of the finished fabric. The method involves (i) a standardized staining procedure to apply a uniform stain on the fabric, (ii) instrumental evaluation of photodegradation of stain in terms of K/S using a template to reduce error, and (iii) analysis of K/S values to evaluate stain degradation in percentage and its comparison with visual assessment. This method has been found to give a reproducible and comparable assessment of stain degradation on the textile material with respect to UV exposure. Page(s): 74-82