chapter 7 Flashcards
what is a Nonwoven Fabrics
-Textile materials bonded
together by entangling fiber or filaments
mechanically, thermally or chemically.
-made by weaving or knitting and
do not require converting the fibers to yarn.
DISPOSABLE
-Is a good one for one use
-not expensive
-mainly used for cleaning products
- The major fiber used for disposable
nonwovens is rayon.
DURABLE
-not intended to be
thrown away after a single use.
-Durable nonwovens are often used as a small but
important component of a total garment or
industrial application.
- Durable nonwovens are used for apparel
interlining, carpet and upholstery fabrics
(padding and backing), automotive headliners
and upholstery, insulation, roofing products,
3 Methods of Manufacturing
Nonwovens
- Dry laid system
- Wet laid system
- Polymer laid
Dry laid system
The material structure is formed by manipulating the fibers while in a dry state. This is the most used system worldwide.
Wet laid system
The material structure is formed by having the fibers manipulated while in a wet state. (similar to paper making)
Polymer laid
The material structure is formed by blowing thermoplastic fibers onto a collection surface as the fibers are being extruded.
Needle-punched nonwovens
This material is produced by passing a fibrous (dry-laid) web into a needle punch machine equipped with groups of specially designed needles.
Bonded-Web Nonwovens
-Bonded webs can be made with any staple
fiber and are produced by forming a web of
fibers (web can be formed by carding
machine), air blowing fibers (dry-laid) or with
liquid (wet-laid).
- Fibers are bonded with an adhesive or with heat fusion (if the fibers are thermoplastic).
End Uses of Bonded-Web
Nonwovens
-Bonded-web nonwovens can be unidirectional,
cross laid, or random web.
- Bonded nonwovens are used in disposable items
such as: - Hospital protective gowns, disposable bed
sheets, towels, tablecloths, cooks hats. - Brand names include Vileda®, Webril®,
Hydraspun
Spunlaced Nonwovens
- formed by the entanglement of staple fibers, using needlelike, high pressure water jets on the web
(wet-laid). - The fibers knot or curl around each other,
causing mechanical binding. No binders are
used. - End uses include medical robes, mattress pads,
backing of quilted tablecloths and sanitary
products. - Brand names include Sontara® by Dupont.
Spunbonded Nonwovens
-Spunbonded nonwovens are made immediately
after fibers are extruded from spinnerets.
(polymer laid)
- They consist of randomly oriented filament
fibers laid down on a fast moving conveyer
belt, consolidated by thermal bonding,
mechanical entanglement, adhesive bonding or
etched filament surfaces to interlock the
fibers. - Since the fabric production is combined with
fiber production, the process is generally more
economical than when using staple fiber to
make nonwoven fabrics.
End uses of Spunbonded Nonwovens
-carpet backing, geotextiles, clothing
interliners, shoelinings, envelopes (Tyvek®), disposable
medical products.
- This method produces the second largest amount of
nonwovens.
Melt-Blown Nonwovens
-made by extruding the polymer through a single-extrusion orifice into a high-velocity, heated-air stream that
reduces the filaments to microdenier size and breaks the filaments into staple fibers.
-The fibers are propelled onto a collection
surface and are held together by a
combination of fiber interlacing and thermal
bonding.
-The fiberweb strength is low and abrasion
resistance is low.
Melt-Blown Nonwovens end-use
insulation (Thinsulate®),
hospital/medical products,battery separators.