44
N. Vigneshwaran and A. Arputharaj
to enhance its scope of application. Various chemical and polymeric treatments are
traditionally used to impart functionalities like durable press finish [1, 2], wrinkle
resistant and flame retardant finish [3], water and oil repellent finish [4], perfumed
finish [5], better dyeability [6] and abrasion resistance finish [7].
Recently, various natural biomaterials are being used to impart diversified functionalities to cotton textiles. Cotton textiles finished with Aloe vera gel having
1,2,3,4-butanetetracarboxlic acid as crosslinking agent is reported to show excellent antibacterial property [8] due to destruction of bacterial cell wall. Similarly,
neem seed extract treated fabric could impart antibacterial activity in cotton textiles having fastness up to five machine washes [9]. The use of combination of aloe
vera, chitosan and curcumin on cotton substrate imparts antibacterial property having fastness up to twenty five washing cycles [10]. The Gallnut extract is used to
impart antioxidant property in cotton textiles [11]. In many cases, the natural dyes
could add multifunctional properties in addition to its primary aim of colouring the
cotton fabrics [12–15]. In spite of numerous research work being carried out to use
the natural materials for functional finishing of cotton textiles, the issues like affinity
to cotton textiles, uniformity and stability of natural materials/dyes, less wash/light
fastness and lack of adequate availability limits their use on an industrial scale.
Nanotechnology during the last two decades revolutionized every fields of science
and technology with the first ever industrial application in textiles. Nanotex
® is
a leading fabric innovation company, started in 1998, provides nanotechnologybased textile enhancements to the apparel, home and commercial/residential interiors
markets. This company replicated the natural Lotus leaf phenomenon in the textiles
using nanomaterial finish. This was followed by numerous research and development
activities in the field of nanofinish in cotton and synthetic textiles. This chapter
focuses on the methods of nanofinish and various multi functionalities that could be
achieved using nanofinish in cotton textiles. Figure 1 shows the possible advantages
of nanofinish as compared to conventional finishes using chemicals and polymers.
2 Nanomaterials Finishing Techniques
Most of the research work has been reported to establish the UV absorption properties
metal oxide nano particles such as TiO 2 , ZnO, Al 2 O 3 , CeO 2 on textile materials. The
functionalization of textile fabrics with NPs to improve the ability of the fabric to
block UVR can be achieved by ex situ and in situ methods. Ex situ methods consist
of two steps: (1) Top down or bottom up approach to synthesize nanoparticles, (2)
Application of nanoparticles to textiles by means of wet-chemical procedures. For
fixing the nanoparticles to fabrics, the steps include impregnating with a wet pick-up,
drying followed by curing process. Wherever required, binders or cross-linkers are
also added to fix the nanoparticles on the surface of textiles materials.
Wang et al. [16] synthesized dumb-bell shaped nano-ZnO and applied on cotton
fabric by pad-dry-cure method. They observed that the higher the curing temperature
employed better the UPF was achieved. The UPF of more than 400 has been achieved
N. Vigneshwaran and A. Arputharaj
to enhance its scope of application. Various chemical and polymeric treatments are
traditionally used to impart functionalities like durable press finish [1, 2], wrinkle
resistant and flame retardant finish [3], water and oil repellent finish [4], perfumed
finish [5], better dyeability [6] and abrasion resistance finish [7].
Recently, various natural biomaterials are being used to impart diversified functionalities to cotton textiles. Cotton textiles finished with Aloe vera gel having
1,2,3,4-butanetetracarboxlic acid as crosslinking agent is reported to show excellent antibacterial property [8] due to destruction of bacterial cell wall. Similarly,
neem seed extract treated fabric could impart antibacterial activity in cotton textiles having fastness up to five machine washes [9]. The use of combination of aloe
vera, chitosan and curcumin on cotton substrate imparts antibacterial property having fastness up to twenty five washing cycles [10]. The Gallnut extract is used to
impart antioxidant property in cotton textiles [11]. In many cases, the natural dyes
could add multifunctional properties in addition to its primary aim of colouring the
cotton fabrics [12–15]. In spite of numerous research work being carried out to use
the natural materials for functional finishing of cotton textiles, the issues like affinity
to cotton textiles, uniformity and stability of natural materials/dyes, less wash/light
fastness and lack of adequate availability limits their use on an industrial scale.
Nanotechnology during the last two decades revolutionized every fields of science
and technology with the first ever industrial application in textiles. Nanotex
® is
a leading fabric innovation company, started in 1998, provides nanotechnologybased textile enhancements to the apparel, home and commercial/residential interiors
markets. This company replicated the natural Lotus leaf phenomenon in the textiles
using nanomaterial finish. This was followed by numerous research and development
activities in the field of nanofinish in cotton and synthetic textiles. This chapter
focuses on the methods of nanofinish and various multi functionalities that could be
achieved using nanofinish in cotton textiles. Figure 1 shows the possible advantages
of nanofinish as compared to conventional finishes using chemicals and polymers.
2 Nanomaterials Finishing Techniques
Most of the research work has been reported to establish the UV absorption properties
metal oxide nano particles such as TiO 2 , ZnO, Al 2 O 3 , CeO 2 on textile materials. The
functionalization of textile fabrics with NPs to improve the ability of the fabric to
block UVR can be achieved by ex situ and in situ methods. Ex situ methods consist
of two steps: (1) Top down or bottom up approach to synthesize nanoparticles, (2)
Application of nanoparticles to textiles by means of wet-chemical procedures. For
fixing the nanoparticles to fabrics, the steps include impregnating with a wet pick-up,
drying followed by curing process. Wherever required, binders or cross-linkers are
also added to fix the nanoparticles on the surface of textiles materials.
Wang et al. [16] synthesized dumb-bell shaped nano-ZnO and applied on cotton
fabric by pad-dry-cure method. They observed that the higher the curing temperature
employed better the UPF was achieved. The UPF of more than 400 has been achieved