NON WOVEN FABRICS

Presented by: Lucky Vankwani TMM1Asad Jafri AMM1

WHAT DOES WIKIPEDIA SAY?

Non-woven textiles are those which are neither woven nor knit, for example felt. Non-wovens are typically not strong (unless reinforced by a backing), and do not stretch. They are cheap to manufacture.

NON-WOVEN Introduction Web formation methods Bonding Systems Discussion

INTRODUCTION

It eliminates the yarn production process and makes the fabric directly from fibers.

Polymers

Fibers

Yarns

Woven Knitted Braided Non-woven

Fabrics

Textile Medical Products

FACTS & TRIVIA

Advantages of n Non-woven

fabrics

the fabric production

itself is faster than

conventional methods

the speed with which the final

fabric is produced

the fabric production

itself is faster than

conventional methods

PRODUCTION RATEFabric production method

Rate of fabric production

Weaving 1 m/min

Knitting 2 m/min

Nonwoven 100 m/min

MAKING NON-WOVEN PRODUCTS

There are normally two steps for making non-woven products.

1. Bonding systems2. Web formation.

BONDING SYSTEMS

BONDING SYSTEMS

Bonding systems in non-wovenNeedled felts

Adhesives

Heat bonding

Stitch bonding

BONDING SYSTEM1) NEEDLED FELTS

Fibres which have no directional frictional properties need to be mechanically entangled in order to form felts.

This is done using barbed needles.

Cross section of a needle-punched bonded fabric.

Needle punching

BONDING SYSTEM2) ADHESIVES

For most nonwoven applications, fibre-to-fibre friction does not provide enough strength.

Adhesive can be effective in holding the fibres together. The properties of an adhesive-bonded nonwoven depend to

quite a large extent on the properties of the adhesive polymer used.

BONDING SYSTEMS3)HEAT BONDING

When a web of thermoplastic fibres (polyester, nylon) or filament is heated, the fibres cross over each other at many points.

This way, the resultant fabric has desirable textile properties.

Such melt-welded fabrics are called Melded fabrics.

Melt-bonding at selected points to give extra stability to a spun bonded geotextile

STITCH BONDING Webs may also be given extra strength by stitching

them through with yarns. Such structures are usually more flexible and less paper-

like than heat-bonded or adhesive bonded nonwovens. Stitch bonding is based on principle of warp knitting.

Sharp-pointed needles pierce the base and loop binding yarns through it.

In this way, relatively cheap but stable fibres, with or without pile, can be produced.

Carpet underfelts are often stitch-bonded.

APPLICATIONS

Non-woven materials are used in numerous applications, including:

Hygiene Baby diapers Feminine hygiene Adult incontinence products

Wipes Domestic Technical

Filters Geotextiles Carpet backing Composites Astro-turf

WEB FORMATION

WEB FORMATION A nonwoven fabric is basically a web of

fibers held together in some way.

The web may be made of Staple Fibres or Filaments, or from portions of polymer film.

WEB FORMATION

THROUGH STAPLE FIBRES

PARALLEL-LAID WEB FROM CARDED FIBERS In a carded

web the fibers are parallel to each other and to the direction in which the card produces the web, making it stronger when pulled lengthwise than crosswise.

CROSS LAID-WEB

To increase the strength of web in both lengthwise and crosswise directions, cross laid web is used.

WEB FROM STAPLE FIBRESRANDOM WEB (3)

The Rando-Webber creates such a randomly orientated web by blowing the fibres about in a stream of air and then sucking them onto the surface of a perforated drum to form a layer.

PHOTOSRANDOM WEBS

To increase the strength of web in both lengthwise and crosswise directions, cross laid web is used.

OTHER WEB FORMATION METHODS Apart from carding methods (dry-laid),

webs from short staple fibres are created by Wet laying.

Wet laying is used in paper-making. The pulped fibres are mixed with water and then scooped into uniform layers on wire screens or on rotating, perforated drums.

Short, acrylic fibres are made into a wet-laid web from a salt solution. As the water evaporates, the salt chemically bonds the fibres into a strong, synthetic, water proof paper.

WEBS FROM FILAMENT

WEBS FROM FILAMENT It is possible to tangle filaments together to

form a web. Such webs are much stronger than web made from staple fibres.

The thermoplastic filaments are welded to each other to form a strong fabric suitable for curtains & tablecloths.

Sometimes, the filaments are textured before web formation. This allows greater extensibility of the fabric in use.

NEW WEB FORMATION METHOD Spun-laced webs is a new method of

entangling fibres to create lace-like nonwoven fabrics uses fine, precisely controlled, jets of water.

The resultant fabric does not need any further reinforcing by heat or adhesive.

It is pliable, resistant to damage during washing, drip-dry, light, warm and soft, excellent for curtains, table cloths and other lace-type application.

CONCLUSION This section we discussed what non-

wovens are and their applications in textile.

We also discussed the web formation methods for both staple fibres and filament fibres.