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Applications in the textile field of sol-gel processes were widely investigated since coatings of fabrics by materials of nanometric size obtained by sol-gel methods represent a functional surface modification attracting even more attention. However, few experiences of the use of nanostructured coatings are reported for leather finishing. In the experiments reported in the present chapter, a nabuk leather was finished by a sol-gel process to confer hydro and oil-repellency. The silica component could act as a protective coating, improving the rubbing performance of the substrate and conferring a certain grade of hydrorepellency, while the oil repellency was due to a fluorocarbon component. The coatings were applied at low add-on of finishing agent with the aim to keep possibly unvaried the esthetic and hand characteristics of the original leather. Contact angle and sorption time measurements of water and oil drops were carried out on the treated samples and compared with the untreated one. A similar comparison was made by testing color fastness to rubbing and change of esthetic appearance. Finally, chemical surface characterization was carried out by Fourier Transform Infrared in Attenuated Total Reflectance (FTIR-ATR) analysis.

Ultraviolet (UV) radiations can act in different ways on the functionalization of textiles, through pre- or posttreatments, in order to modify their behavior in dyeing and finishing processes. In cotton fiber, unlike the wool, the UV absorption is not due to any of the structural groups of the normal cellulosic chains and can only be attributed to "impurities" or "faults" bearing carbonyl and/or carboxyl groups. In fact, UV irradiation coupled with mild oxidation can improve some properties of the cotton fibers such as pilling resistance, water swelling, and dyeability. Therefore, the process of differential dyeing with direct and reactive dyes assisted by UV irradiation was studied and interesting differential chromatic effects were obtained by a UV post-treatment capable to fade dyeing. On the other hand, the surface modification of cotton fabrics by UV curing and UV grafting with suitable chemicals was pursued to obtain finishing treatments able to confer oil and/or water repellency. Finally, antimicrobial finishing by chitosan UV grafting was proposed as valid environmental friendly method to confer a satisfactory washing-resistant antimicrobial activity to cotton fabrics even with low polymer add-on

The modification of the surface energy of textile fibers to improve functional properties such as the wettability was reviewed. This modification can be achieved by physical or chemical methods or by the combination of both. Applications of plasma treatment to improve the wettability of natural and synthetic fibers were considered and some methods of wettability measurement were mentioned. Subsequently the methods aimed to confer water and oil repellency were discussed and the treatment by UV curing of fluorochemicals was explained in detail. Finally the sol-gel techniques useful to modify the surface properties of textiles were introduced and the results of water and oil repellency achievable by sol-gel were presented