*3.1.1 Natural fibers*

Natural fibers, as the name suggests are obtained from nature. The natural sources for these fibers can be plants, animals or minerals (**Figure 1**). **Figure 2** shows the classification of vegetable based cellulosic fibers. The fibers obtained from plants include

*Natural Fibers: The Sustainable Alternatives for Textile and Non-Textile Applications DOI: http://dx.doi.org/10.5772/intechopen.106393*

cotton, kapok (from seeds), sisal, banana, pineapple (obtained from leaves) and bast fibers like jute, flax, hemp, kenaf, ramie, etc. (obtained from plant's stems). Cellulose fiber extensively used in textile industry include cotton, linen, flax, hemp and jute. A variety of fashion ensembles ranging from cotton canvas satchels, tote bags, tapestry luggage to sports socks, sneakers, bandanas, handkerchiefs, scarfs, stoles, hats and caps uses cotton as the major raw material.

The salient features of cotton fiber that makes it suitable for a range of apparels and accessories include its softness, breathability, moisture absorbency and temperature regulation property. The natural textured surface of fiber in addition to its moisture absorption provides comfortable feel and breathability next to skin. Accordingly, the fiber is preferred for applications where rapid water absorption is the prime concern like terry-cloth apparel such as beach coats. Moreover, cotton is versatile, easy to care and handle fiber that is not just static free, hypoallergenic, and pill free but also has the ability to retain its original feel and color. The above stated attributes make cotton year round fiber suitable in both warm as well as cold weather.

*Kapok* belongs to the Bombacaceae family and is generally cultivated in tropical regions. Kapok seeds are enclosed within the fiber. The cellulosic fiber features yellowish or light brown color, light weight and hydrophobicity. Kapok fiber is preferably utilized as adsorption, oil absorbing, buoyancy material, apart from being used as biofuel and reinforcement material.

*Flax* is cellulosic fiber in crystalline form featuring a length of 90 cm and diameter of 12–16 μm. Flax is mainly cultivated in Canada, Netherlands, Belgium and France. The stem of plant L. usitatissimum is the fiber source. The fiber extraction is accomplished by two processes namely retting and scorching to alter the fiber properties. The enzymatic application during retting process causes pectin degradation thereby

**Figure 2.**

resulting in separation of fibers. Flax fiber is extensively used for production of linen besides being used in furniture, home textiles and interior decor items.

*Ramie fiber* is herbaceous perennial plants extracted from the plant steam, is extensively grown in China, Japan and Malaysia. Ramie is considered to be one of the fast growing, strongest and longest among natural bast fibers featuring a height of 1–2 m. Ramie fiber is processed in a similar manner as linen from flax. The fiber finds wide range of applications such as apparels like sweaters and cardigans, upholstery, marine packing, gas mantle, fishing nets, automotive, furniture, construction, pulp, paper, agrochemicals and composites etc.

*Jute* is primarily grown in Asian countries like India, Bangladesh, China, and Myanmar and it takes about 4 months to grows up to height of 15–20 cm. The extraction of fibers is accomplished about 4 months after its cultivation. The fibers are subjected to chemical or biological retting process which is essential for pectin removal between bast and wood core. The chemical retting process involves the application of chemicals like N2H8C2O4, Na2SO3, etc. while biological retting involves soaking the bundled stalks in water for about 20 days enabling the removal of pectin between the bast and the wood core thereby assisting in easy fiber separation. Subsequently, the fibers are allowed to dry.

*Kenaf* belongs to bast fibers and are extracted from flowers, outer fiber (bast comprising 40% of the stalks dry weight) and inner core (comprising 60% of stalks dry weight). The processing of kenaf plants upon harvesting is accomplished with a mechanical fiber separator, consuming whole stalk in pulping followed by chemical or bacterial treatment of extracted fibers for their separation from the non-fibrous content such as wax, pectin, and other substances. The fiber exhibits unique properties like biodegradability and eco-friendly attributes, stiffness, strength, toughness and high resistance to insecticides. Kenaf fiber primarily find application in production of paper, rope, cords, storage bags along with textile applications. More recently, *Natural Fibers: The Sustainable Alternatives for Textile and Non-Textile Applications DOI: http://dx.doi.org/10.5772/intechopen.106393*

kenaf fiber is utilized for composites apart from application in furniture, construction, packaging, automotive sector.

*Coir Fiber,* one of the thickest natural fiber is mainly cultivated in tropical regions including India, Sri Lanka, Indonesia, Philippines, and Malaysia and is obtained from the husk of the coconut fruit.

Coir fiber in contrast to other natural fibers has higher lignin and lower cellulose and hemicellulose content and features a high microfibrillar angle thereby rendering it several valuable properties, such as strength, resilience, resistance to weathering, and high elongation at break. The salient properties of coir fiber make it a suitable candidate for a range of applications such as upholstery, ropes, mats, mattresses, agriculture, construction, brushes etc. [5–7].

Another natural fiber that is gaining interest among textile designers for designing clothing, footwear and handbags is linen. Hemp and jute are rope like fibers and exhibit coarseness compared to linen and generally preferred for apparels and accessories that demand rough texture and durability. Hemp, jute is finding applications in accessories like fashion jewelry, handbags, belts, hair accessories, footwear, bag-pack, tote, gunny-bags and mobile covers.

Jute is a plant based multicellular fiber characterized by nodes and cross markings in longitudinal view and polygon shapes in cross-section. Jute is hygroscopic in nature with moisture regain of 12–14% and its color varies from yellow to brown to gray and is good insulator of heat and electricity. Jute fiber is used for making burlap, hessian, gunny cloth which serve as raw materials for accessories like handbags, jewelry etc.

Bamboo and straw are another plant based fibers gaining popularity among fashion designers. Bamboo is wood like tropical grass while the sources for straw are wheat stalks, grasses, sisal hemp and rice paper. Summer wear hats, hair accessories, different handbags are designed from straw, bamboo or strips of bamboo woven like straw. The pliability and sturdy hand of bamboo canes make them suitable for gripping elements and handles for handbags. However, straw is generally preferred for delicate fad accessories trending in a single season which is accounted to its inferior durability and flex abrasion resistance. Repeated bending in one position may cause fiber breakage hampering the esthetic appeal of accessory and rendering it useless.

The fibers such as wool (obtained from sheep) and silk (obtained from silk worm cocoons) are protein based fibers and finding applications in a variety of accessories. Pashmina (cashmere or cashmere/silk blend), wool and silk are used for designing exclusive and high priced stoles, scaves and other winter wear accessories. Pashmina is obtained from the underbelly of the Capras goat found in India's Himalayan mountains. Wool is easily distinguishable from hair or fur fibers showcasing crimpy appearance and elasticity. Fabrics made from wool fiber exhibit durability owing to tear and snag resistance and anti-pill properties. Moreover, wool fabrics provide easy care and handling properties, drapes stunningly, and maintains resilience in wet condition. The most crucial property of wool fiber of providing insulation by holding air layer next to the skin makes the fiber a preferred choice for winter wear apparels and accessories. Henceforth, winter wardrobe is incomplete without the inclusion of wool based hats and scarfs.

Another natural protein fiber namely silk is composed of fibroin and is the product of insect larvae that forms cocoon. The most exclusive variety of silk is obtained from the cocoons of the larvae of the mulberry silkworm *Bombyx mori*. Silk is considered to be the most luxurious of all fibers characterized by unique natural luster. Triangular prism like structure of the silk fiber is responsible for its shimmering

appearance allowing silk fabric to refract incident light at different angles, thereby producing varying color effects. The silk fiber has an additional advantage of being one of the strongest natural fibers and offers remarkable abrasion resistance with many years of service to wearer.

Furthermore, the fiber provides extremely soft texture, is elastic and displays the ability to retain its original shape with minimal shrinkage.

The unique properties of this protenecious fiber available in filament form make it the most anticipated option for apparel and accessory designers to render a loyal, pleasing look to end products. The fabrics produced from this luxurious fiber however, need special care as far as dry cleaning, washing and pressing is concerned. Manual washing of silk apparels and accessories is usually recommended unless the end products have been processed for machine laundering. Moreover, the exorbitant prices of silk fiber prompt designers to look for cheaper substitutes that resemble silk, such as polyester and nylon microfibers.

Vegetable fibers like ramie, jute and hemp in contrast to hair fibers are economical and are characterized by rigid feel, coarseness and brittleness and thus find application in designing textile products where strength, abrasion resistance and rough texture are the requisites. The fibers are thus generally preferred for designing lower priced accessories like fashion jewelry, belts, handbags. Asbestos is the natural mineral fiber known for its fireproofing and insulating properties. Accordingly, the fiber was utilized for flame retardant protective clothing. However, the fiber has limited application in textile arena in recent times owing to its carcinogenic nature and hazards to lungs by continued inhalation of asbestos fiber.

#### *3.1.2 Man-made fibers*

Man-made fibers also referred to as synthetic or artificial fibers are the fibers that are developed by mankind to meet the ever increasing demands of fibers in textile and fashion industry since the sources of natural fibers are on the verge of depletion. Moreover, the stringent animal rights discourage slaughtering of animals for their skin, fur and hair fibers. Therefore, the man-made fiber industry is bound to grow tremendously. The man-made fibers are manufactured with the aim of cutting down costs associated with natural fibers and at the same time achieving desirable properties like high strength, abrasion resistance, soft feel, drape ability and varied textures. Manmade fibers are classified into regenerated, synthetic and miscellaneous inorganic fibers on the basis of raw materials employed for their manufacture. Regenerated fibers like viscose rayon, cuprammonium rayon, acetate, triacetate, casein, rubber are the man-made fibers that belong to cellulosic group and are produced using natural polymers i.e. cellulosic base materials thus requiring minimum chemical steps [1–4].

Acetate it has trade name of Ariloft, Chromspun had a luxurious feel and appearance, is available in a wide color range, drapes extremely well, is relatively fast drying and is resistant to shrinkage, mildew and moth. It is used for blouses, dresses, foundation garments, lingerie, linings, shirts, slacks and sportswear.

The non-cellulosic group include fibers like nylon, polyester, acrylic, polyolefin, spandex, glass and teflon which are protein based fibers. These fibers constitute of molecules of carbon, hydrogen, nitrogen and oxygen derived from petroleum and natural gas. The fibers manufactured by synthesizing various chemicals like the petroleum products are classified as synthetic manmade fibers. Natural raw materials are not required as a base material for their manufacture unlike the regenerated ones.

#### *Natural Fibers: The Sustainable Alternatives for Textile and Non-Textile Applications DOI: http://dx.doi.org/10.5772/intechopen.106393*

Nylon fiber belonging to this group is manufactured using hexamethylenediamine and adipic acid while polyester uses dimethyl terephthalate and ethylene glycol in its production. The process basically involves conversion of chemicals into fiber forming substances which can be drawn into filaments of required coarseness or fineness.

Nylon is known for its exceptional strength, abrasion resistance and easy care properties making it desirable fabric for hosiery, blouses, dresses, lingerie, underwear, raincoats, ski wear and suits.

Acrylic is also referred to as Acrilan, Orlon and Zefran. The fiber is characterized by its soft feel, warmness, wool like texture and light weight. Moreover, the acrylic fiber fabrics display considerable strength, resilience, drying ability, and are resistant to moths, sunlight, oil, and chemicals. Therefore, fabrics made of acrylic fiber namely fleece, fake furs, jerseys find application in winter wear and knitted accessories along with apparels like dresses, infant wear, knitted garments, skirts and sweaters. Modacrylic, another synthetic fiber is used for fabrication of fleece and knit pile fabrics. The fabrics owing to their softness, resilience, abrasion and flame resistance, drying ability, and shape retention, are preferred for deep-pile coats, linings, simulated fur accessories and hair accessories.

Olefin is another organic man-made fiber that exhibits excellent colorfastness, extreme strength, resistance to mildew and perspiration and is thus, is garnering designer's attention for designing of knitted accessories, winter wear and sportswear apparels and accessories.

Another fiber that has taken the apparel and accessory industry by storm is rayon fiber which offers multitude advantages of being soft, comfortable and easily dyeable. Consequently, the fiber is preferred choice for a variety of apparels and accessories like sportswear, blouses, jackets, lingerie, rainwear, shirts, scarves, stoles and ties.

Spandex Produced extensively by Dupont as Lycra, its major advantage is its ability to be stretched 500 percent over and over without breaking, always returning to its original length. It is lightweight, more durable than rubber, and resistant to body oils, it is used wherever stretch is required such as in athletic apparel, bathing suits, foundation garments, ski pants and sportswear.

Miscellaneous inorganic group comprises of fibers which use substances like metal and glass in their manufacture. The malleability and ductility of the inorganic fibers render them usable for textile applications. However, high cost and technical difficulties offers hindrance to wide spread acceptance of the fibers [5, 8].
