Nonwoven | Applications of Nonwovens | Production of Nonwovens

Introduction of Nonwoven  
An average person is unlikely to be familiar with the term Nonwovens and a few decades back there were no experts in this field. When the consumer hears the term Nonwovens it makes him think of something, which is not like traditional woven fabrics, something modern, advanced, hygienic, but he is not aware of any specific types of materials among those which carry the same name. But now the precise meaning of the term is somewhat clearer to the experts. According to the experts, Nonwovens is a class of textiles/sheet products, unique in industry, which is defined in the negative; that is, they are defined in what they are not. Nonwovens fabrics are different than the conventional textile fabrics and paper. Nonwovens are not based on yarns and (with frequent exceptions) do not contain yarns. They are based on webs of individual fibers. Nonwovens are different than paper in that nonwovens usually consist entirely or at least contain a sizeable proportion of long fibers and/or they are bonded intermittently along the length of the fibers. Although paper consists of fiber webs, the fibers are bonded to each other so completely that the entire sheet comprises one unit. In nonwovens we have webs of fibers where fibers are not as rigidly bonded and to a large degree act as individuals.

The definitions of the nonwovens most commonly used nowadays are those by the Association of the Nonwovens Fabrics Industry (INDA) and the European Disposables and Nonwovens Association (EDANA).

1.1.INDA definition:
Nonwovens are a sheet, web, or bat of natural and/or man-made fibers or filaments, excluding paper, that have not been converted into yarns, and that are bonded to each other by any of several means.

The various methods for bonding are:

  • Adding an adhesive
  • Thermally fusing the fibers or filaments to each other or to the other meltable fibers or powders.
  • Fusing fibers by first dissolving, and then resolidifying their surfaces.
  • Creating physical tangles or tuft among the fibers.
  • Stitching the fibers or filaments in place.
1.2.EDANA definition:
Nonwovens are a manufactured sheet, web or bat of directionally or randomly oriented fibers, bonded by friction, and/or cohesion and/or adhesion, excluding paper or products which are woven, knitted, tufted stitch bonded incorporating binding yarns or filaments, or felted by wet milling, whether or not additionally needled. The fibers may be of natural or man-made origin. They may be staple or continuous or be formed in situ.

2.Uses of Nonwovens
Nonwovens find numerous applications ranging from baby diapers to industrial high performance textiles. Some of the important areas where nonwovens are treated as primary alternative for traditional textiles as Geotextiles, materials for building, thermal and sound insulating materials, hygienic and health care textiles and automotive industries. Nonwovens are also used in cover stocks, agriculture, aerospace, home furnishings etc. Although it is not possible to list all the applications of nonwovens, some of the important applications are listed in Table 1.


Table 1 - Products That Use Nonwovens
Agriculture  and    Landscaping 
Home Furnishings
Industrial/Military
Crop Covers
Furniture construction sheeting
Coated fabrics
Turf protection products
Insulators, arms and back
Filters
Nursery overwintering
Cushion ticking
Semiconductor polishing pads
Weed control fabrics
Dust covers
Wipers
Root bags
Decking
Clean room apparel
Containers
Skirt linings
Air conditioning filters
Capillary matting
Pull strips
Military clothing

Bedding construction sheeting
Abrasives
Automotive
Quilt backing
Cable insulation
Trunk applications
Dust covers
Reinforced plastics
Floor covers
Flanging
Tapes
Side liners
Spring wrap
Protective clothing, lab coats
Front and back liners
Insulators
Sorbents
Wheelhouse covers
Quilt backings
Lubricating pads
Rear shelf trim panel covers
Blankets
Flame barriers
Seat applications
Wallcovering backings
Packaging
Listings
Acoustical wallcoverings
Conveyor belts
Cover slip sheets
Upholstery backings
Display felts
Foam reinforcements
Pillows, pillow cases
Papermaker felts
Transmission oil filters
Window treatments
Noise absorbent felt
Door trim panel carpets
Drapery components

Door trim panel padding
Carpet backings, carpets, and
Leisure, Travel
Vinyl, landau cover backings
Pads
Sleeping bags
Molded headliner substrates
Mattress pad components
Tarpaulins, tents
Hood silencer pads

Artificial leather, luggage
Dash insulators
Health Care
Airline headrests, pillow cases
Carpet tufting fabric and under
Surgical: caps, gowns, masks,

Padding
Shoe covers
Personal Care and Hygiene

Sponges, dressings, wipes
Diapers
Clothing
Orthopedic padding
Sanitary napkins, tampons
Interlinings
Bandages, tapes
Training pants
Clothing and glove insulation
Dental bibs
Incontinence products
Bra and shoulder padding
Drapes, wraps, packs
Dry and wet wipes
Handbag components
Sterile packaging
Cosmetic applicators, removers
Shoe components
Bed linen, underpads
Lens tissue

Contamination control gowns
Hand warmers
Construction
Electrodes
Vacuum cleaner bags
Roofing and tile underlayment
Examination gowns
Tea, coffee bags
Acoustical ceilings
Filters for IV solutions, blood
Buff pads
Insulation
Oxygenators and kidney

House wrap
Dialyzers
School, Office
Pipe wrap
Transdermal drug delivery
Bookcovers


Mailing envelopes, labels
Household
Maps, signs, pennants
Asphalt overlay
Wipes, wet, dry polishing
Floppy disk liners
Road and railroad beds
Aprons
Towels
Soil stabilization
Scouring pads
Promotional items
Drainage
Fabric softener sheets
Pen nibs
Dam and stream embankments
Dust cloths, mops

Golf and tennis courts
Tea and coffee bags

Artificial turf
Placemats, napkins

Sedimentation and erosion
Ironing board pads

Control
Washcloths

Pond liners
Tablecloths

Source: The Nonwoven Fabrics Handbook, Association for the Nonwoven Fabrics Industry, Cary, North Carolina

3.PRODUCTION AND SHIPMENTS OF NONWOVENS
The Nonwoven industry is one of the fastest growing industries in the world. It is rapidly developing a sophisticated and diverse market. It has been exhibiting an average growth of about 10% over the past twenty years and should continue this rate of growth in the next ten years. The technology in Nonwoven industry has been improved significantly in nearly all available major manufacturing processes, including those of spun bond, meltblown, needle punched, spunlaced, wet laid and dry laid fabrication. The most important point in rapid development and commercial acceptance of nonwovens is the ability to produce materials of special properties in less time and at reasonable prices. The relative production speeds of various textile technologies are compared in Table 2.


Table 2 Relative production rates of different Textile technologies
Technology
Relative Production Rate
Weaving
1-6
Knitting
3-16
Nonwovens - web forming:
-Carding
-Spunbond
-Wet-laid

120-400
200-2000
2300
Nonwovens - bonding
-Stitchbonding
-Needling
-Calendaring
-Hot air bonding

40
30-500
2000
5000

A large number of fibers are available n the market, but the Nonwovens market is mainly dominated by three fibers, namely polyolefin’s, polyester, and rayon. These three fiber types make up a substantial part of the overall Nonwovens markets for fibers. The North American Nonwovens industry is the largest in the world and accounts for almost one third of the worldwide sales of roll goods - around $2.8 billion - in 1997, according to estimates from the Association of the Nonwovens Fabrics Industry (INDA). A major portion of the polyolefin and polyester fiber in the U.S. market is consumed by the Nonwovens industry. Last year (1998), 57% of the polyolefin share was consumed by the Nonwovens industry and only 43% was consumed by all the other industries, in spite of the fact that polyolefin’s are the major raw products for the packaging industry. Even in the case of polyesters, the share has increased to 14%. The major share of polyester fiber goes to high loft industry.


 Table 3: U.S. shipments of olefin staple: Nonwovens Vs Other Markets, 1989-1998
YEAR
Total U.S.
Shipped to Nonwovens
All Other
1989
363
195
168
1990
388
233
155
1991
438
272
166
1992
441
259
182
1993
466
276
190
1994
489
280
209
1995
458
267
191
1996
515
295
220
1997
542
314
229
1998
596
339
257
CAGR, 1989/98
5.6%
6.4%
4.9%
Source: Fiber Economics Bureau and Trade Estimates, CAGR- Compound annual growth rate.

Table 4: Relative production of differnet textile technologies

YEAR
Total U.S.
Shipped to Nonwovens
All Other
1989
2261
272
1989
1990
2015
240
1775
1991
2128
237
1891
1992
2191
244
1947
1993
2158
263
1895
1994
2221
280
1941
1995
2100
280
1820
1996
2016
285
1731
1997
2250
285
1965
1998
2105
292
1813
CAGR, 1989/98
-0.7%
0.8%
-1.0%
 Source: Fiber Economics Bureau and Trade Estimates

The production of Nonwovens amounts to approximately 20% of the total production of textiles and this percentage grows year by year. The world production of Nonwovens is shown in Table 5. The growth rates of Nonwovens production are extremely high, when compared with the conventional textiles industry.

Table 5. World Production of Nonwoven

2001(tons)
2002(tons)

West Europe

1,115,700
1,203,100
USA
1,024,000
1,074,000
Japan
298000
296000
China
417000
477000
Other AFMA Members
238700
244700
Others
560000
620000
Total
3,653,400
3,915,500


Table 6. Leading producers of Nonwovens



Worldwide Sales
Company
Country
(Millions USD)
Freudenberg
Germany
1,117
DuPont
USA
800
PGI
USA
600
BBA Group
UK
500
Kimberly-Clark
USA
482
Veratec
USA
300
Japan Vilene
Japan
295
Dexter
USA
284
Hoechst
Germany
189
Asahi
Japan
172
Toyobo
Japan
155
Akzo Nobel
The Netherlands
150
Lantor
The Netherlands
132
Walkisoft
Finland
128
Amoco
USA
125

With the nonwovens successfully moving into more technical end-uses, the fiber requirements have also become more important with regard to the fiber properties. The cooperation between fiber supplier and fabric producers is now seen as important criteria for more advancement to come about in the nonwovens field.

References
The Nonwoven Fabrics Handbook, Association of the Nonwoven Fabrics Industry, Cary, NC

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