Nonwoven Fabrics: Raw Materials, Manufacture, Applications, Characteristics, Testing Processes

0 Introduction to nonwovens 1
0.1 Definition of nonwovens 1
0.2 Nonwoven manufacturing processes 3
0.3 Nonwoven properties and applications, including environmental
considerations 4
0.4 Development of the nonwovens industry 6
0.5 Future perspectives 11

Part I Raw materials for the production of nonwovens
1 Fibrous material 15
1.1 Natural fibres 15
1.1.1 Vegetable fibres 15
1.1.2 Animal fibres 20
1.2 Chemical fibres 21
1.2.1 Chemical fibres made from natural polymers 22
1.2.2 Man-made fibres from synthetic polymers 32
1.2.3 Modification of synthetic fibres 69
1.3 Other fibres made in industrial processes 74
1.3.1 Glass fibres 74
1.3.2 Silicate fibres 76
1.3.3 Carbon fibres 76
1.3.4 Boron fibres 76
1.3.5 Metal fibres 76
1.4 Reclaimed fibres 77
1.4.1 Basics 77
1.4.2 Making textile waste into reclaimed fibres 78
1.4.2.1 Pre-treatment 78
1.4.2.2 Principle of reclaiming 79
1.4.2.3 Subsequent treatment 80
1.4.3 Reclaimed fibre quality 80
1.4.4 Reclaimed fibre application 83
2 Other raw materials 87
2.1 Cellulose (Pulp) 87
2.2 Granules 87
2.2.1 General discussion of physical properties 90
2.2.2 Polyolefins 92
2.2.3 Polyesters 93
2.2.4 Polyamides 94
2.3 Powders 96
2.3.1 Polymer powders 96
2.3.1.1 Polyacrylonitrile 96
2.3.1.2 Further copolymers 97
2.3.2 Additives 97
2.3.3 Stabilizers 98
2.3.4 Pigments 99
2.4 Absorbent polymers 100
2.4.1 Absorption mechanism 101
2.4.2 Production process 101
2.4.2.1 Suspension polymerization 101
2.4.2.2 Solution polymerization 102
2.4.2.3 Surface crosslinking 102
2.4.2.4 In-situ polymerization 103
2.4.3 Test methods 104
2.4.3.1 Characteristic data of absorbent polymer 104
2.4.4 Field of application 105
2.4.5 Summary 106
2.5 Spin finishes 106
2.5.1 General 106
2.5.1.1 Definitions 106
2.5.1.2 The requirements placed on spin finishes 107
2.5.1.3 Compositions of spin finishes 108
2.5.2 The application of spin finishes 109
2.5.2.1 Man-made fibre production 109
2.5.2.2 Processing 110
2.5.3 Test methods 110
2.5.3.1 Tests on the spin finishing agent 110
2.5.3.2 Tests on spin finished fibre material 111
2.5.4 Spin finishes on nonwovens 113
2.5.4.1 General 113
2.5.4.2 Nonwoven fabric manufacture and spin finishes 113
2.5.4.3 End product and spin finish 114
2.5.5 Future prospects 115
3 Binders 119
3.1 Introduction 119
3.2 Binder fluids 120
3.2.1 Chemical structure, construction principle 121
3.2.1.1 Monomers 121
3.2.1.2 Functional groups, crosslinking agents 123
3.2.2 Binder fluids and their processing 123
3.2.3 Binder fluids and the properties of nonwoven fabrics 125
3.2.4 Focal points of development 127
3.3 Adhesive fibres 129
3.3.1 Soluble fibres 129
3.3.2 Hotmelt adhesive fibres 130
3.3.2.1 Appearance 130
3.3.2.2 Chemical structure 130
3.3.2.3 Mechanism of bonding 134
3.3.2.4 Properties 136

Part II Processes to manufacture nonwovens
4 Dry-law process 141
4.1 Nonwoven fabrics 141
4.1.1 Fibre preparation 141
4.1.2 Production of fibrous webs by carding 148
4.1.2.1 Roller carding theory 149
4.1.2.2 Plant technology 157
4.1.2.3 Web forming 159
4.1.2.4 Web drafting 168
4.1.3 Fibre webs following the aerodynamic procedure 170
4.1.3.1 Aim of the procedure 170
4.1.3.2 Description of the procedure 170
4.1.3.3 Machines for aerodynamic web forming 174
4.1.4 Perpendicular laid fibrous highlofts STRUTO and ROTIS 180
4.1.4.1 Technologies of production perpendicular laid highlofts 181
4.1.4.2 Properties of perpendicular laid highlofts 185
4.2 Extrusion nonwovens 188
4.2.1 Use of polymers 189
4.2.2 Generally, on the process technology and equipment to be used 192
4.2.3 Processes to make spunlaid nonwovens and composites 204
4.2.4 Processes to make fine-fibre spunbonded nonwovens 221
4.2.4.1 Meltblowing process 221
4.2.4.2 Flashspinning process 224
4.2.4.3 Electrostatic spunbonding 225
4.2.5 Processes to make film nonwovens 225
5 Wet lay method 237
5.1 Principle of the method 238
5.2 Development 238
5.3 Raw materials and fibre preparation 239
5.3.1 Fibre types 241
5.3.2 Production of short-staple fibres 245
5.3.3 Binders 245
5.3.4 Fibre preparation 247
5.4 Construction of wet lay systems 250
5.4.1 Web forming 256
5.4.2 Bonding 262
5.4.2.1 Adding the binder fibres 262
5.4.2.2 Adding binder dispersions to the pulp 262
5.4.2.3 Adding the binder to nonwoven web 263
5.4.2.4 Pressing 264
5.4.3 Web drying 265
5.4.3.1 Contact drying 265
5.4.3.2 Circulating-air dryers 265
5.4.3.3 Tunnel dryers 266
5.4.3.4 Radiation drying 266
5.4.4 Batching 266
6 Web bonding 269
6.1 Needling process 270
6.1.1 The principle of needling 270
6.1.1.1 Batt feeding 272
6.1.1.2 Needling zone 273
6.1.1.3 Felt removal 282
6.1.2 High-performance needling technique 282
6.1.3 Surface structuring 283
6.1.4 Paper machine clothing 286
6.1.5 Needle characteristics 289
6.1.6 Influence of needling conditions on the needle felt’s
chartacteristics 293
6.2 Loop formation processes 302
6.2.1 System of processes 304
6.2.1.1 Stitch-bonding processes 305
6.2.1.2 Stitch-bonding process Malivlies 312
6.2.1.3 Pile stitch-bonding process with base material 318
6.2.1.4 Loop stitch-bonding without base material 320
6.2.1.5 Loop stitch-bonding with double-sided meshing 321
6.2.1.6 Loop stitch-bonding to bond two fabrics by meshing 323
6.2.2 Warp knitting 324
6.2.3 Knitting 325
6.3 Hydroentanglement process 326
6.3.1 Process development 327
6.3.2 Fibre and process influences 334
6.3.3 Bonding lines 336
6.4 Thermal processes 341
6.4.1 Drying 341
6.4.1.1 Convection drying 342
6.4.1.2 Contact drying 352
6.4.1.3 Radiation drying 353
6.4.2 Hot-air bonding 353
6.4.2.1 Basics 353
6.4.2.2 Process technology 355
6.4.2.3 Line technology 359
6.4.3 Heatsetting 361
6.4.4 Thermal calender bonding 363
6.4.4.1 Process technology 364
6.4.4.2 Line technology 367
6.4.5 Ultrasound bonding 369
6.5 Chemical methods 369
6.5.1 Introduction 369
6.5.2 Methods for cohesive bonding 372
6.5.2.1 Cohesive bonding through thermoplasticity 372
6.5.2.2 Cohesive bonding in the case of a dissolved fibre surface 372
6.5.3 Adhesive bonding methods 373
6.5.3.1 Application of liquid binder in excess 374
6.5.3.2 Removal of excess liquor 376
6.5.3.3 Metered binder application to one side 378
6.5.3.4 Application of foamed binder fluids 384
6.5.3.5 Application of powder 386
6.6 Composite materials 389
6.6.1 Nonwoven composites 389
6.6.1.1 Variants of processes 390
6.6.1.2 Bonding by means of needle-punching 391
6.6.1.3 Bonding by means of stitch-bonding 393
6.6.1.4 Bonding by means of entangling 394
6.6.1.5 Bonding by means of glueing 395
6.6.2 Nonwovens suitable to make composite materials 398

Part III Finishing nonwovens
7 Mechanical finishing 411
7.1 Shrinking 411
7.1.1 Creation and removal of distortions 411
7.1.2 Deliberate shrinkage 411
7.2 Compacting and creping 412
7.2.1 Compacting – the Clupak process 412
7.2.2. Creping – the Micrex microcrepe process 413
7.3 Glazing, calendering, pressing 414
7.3.1 Glazing or rolling calenders 414
7.3.2 Embossing or goffering calenders 414
7.3.3 Felt calenders, transfer calenders 415
7.3.4 Rotary pressing machines 415
7.3.5 Moulding, stamping 415
7.4 Perforating, slitting, breaking 416
7.4.1 Perforating 416
7.4.2 Slitting 416
7.4.3 Breaking 417
7.5 Splitting, emerizing, suede finishing, shearing, raising 417
7.5.1 Splitting 417
7.5.2 Emerizing, suede finishing 418
7.5.3 Shearing, raising 418
7.6 Singeing 418
7.7 Sewing, quilting and welding 419
7.7.1 Cover-seaming and quilting 419
7.7.2 Ultrasonic welding 419
7.7.3 High-frequency welding 419
7.8 Other mechanical finishing methods 420
8 Chemical finishing 421
8.1 Washing 421
8.2 Dyeing 422
8.2.1 Stock and spin dyeing 422
8.2.2 Dyeing and bonding 423
8.2.3 Subsequent dyeing 423
8.2.4 Different dyeing methods 424
8.2.5 Cold pad batch dyeing 424
8.2.6 Continuous dyeing 425
8.3 Printing 425
8.3.1 Printing of lightweight nonwovens 425
8.3.2 Printing of heavy nonwovens (needle-punched nonwoven
floor coverings) 426
8.3.3 Spray printing 427
8.3.4 Transfer printing 428
8.4 Finishing, softening, special effects 428
8.4.1 Machine facts and possibilities 429
8.4.2 Stiffening finishes 429
8.4.2.1 Finishing of toe and heel caps on footwear 429
8.4.2.2 Finishing of nonwovens for roofing felts 430
8.4.2.3 Finishing of glass fibre nonwovens for glass fibre composites 430
8.4.3 Softening 430
8.4.4 Antistatic finishing 431
8.4.5 Soil-repellent finishing 432
8.4.6 Water-repellent and oil-repellent finishing 432
8.4.7 Hygiene finishing 432
8.4.8 Flame resistant finishing 433
8.4.9 Absorbent and water absorbent finishing 433
8.4.10 Dust-bonding treatment 434
8.5 Coating 435
8.5.1 Coating methods 435
8.5.1.1 Kiss roll coating 435
8.5.1.2 Rotogravure coating 436
8.5.1.3 Rotary screen coating 436
8.5.1.4 Knife or doctor coating 437
8.5.1.5 Extrusion coating 438
8.5.1.6 Non-contact coating 439
8.5.1.7 Release coating 439
8.5.2 Coating effects 440
8.5.2.1 Non-slip finishing 440
8.5.2.2 Mouldable coating 441
8.5.2.3 Self-adhesive coating 441
8.5.2.4 Foam coating 442
8.5.2.5 Loose lay coating 445
8.5.2.6 Microporous coating 446
8.5.2.7 Drainage coating 446
8.5.2.8 Heat-sealing coating 447
8.6 Laminating 450
8.6.1 Wet laminating 451
8.6.2 Dry laminating 451
8.6.2.1 Use of adhesive nonwovens 452
8.6.3 Examples of laminating 452
8.7 Flocking 454
8.8 New processes and products 455
8.9 Ecology and economy 456

Part IV Peculiarities with regard to ready-making nonwovens
9 The making up of finished products 463
9.1 Concepts and definitions 463
9.2 Product development 465
9.2.1 Product development for garment textiles 465
9.2.2 Product development for decor fabrics and home textiles 468
9.2.3 Product development for technical textiles 468
9.3 Production preparation 469
9.4 Production 471
9.4.1 Spreading 471
9.4.2 Cutting 472
9.4.3 Joining and assembly 477
9.4.4 Ironing 482
9.5 Packaging 483
9.6 Mechanization and automation 483

Part V Characteristics and application of nonwovens
10 Nonwovens for hygiene 489
11 The use of nonwovens in medicine – safety aspects 495
11.1 General requirements 499
11.2 Design and construction 500
11.3 Information to the user 501
11.4 Conclusion 502
12 Nonwovens for cleaning and household products 503
12.1 Market situation 503
12.2 Wet and damp-cleaning products 504
12.2.1 Floor cloths and materials for floor cleaning systems 506
12.2.2 Durable wiping cloths 507
12.2.3 Disposable and semi-disposable wiping cloths 507
12.2.4 Synthetic leather (Chamois type) 509
12.3 Dry and damp-cleaning products 509
12.3.1 Microfibre nonwovens 509
12.3.2 Polyvinyl alcohol nonwovens 511
12.3.3 Impregnated cloths 511
12.4 Scouring media 511
12.4.1 Pan scourers, scouring sponges and pads 512
12.4.2 Floor pads 512
13 Nonwovens for home textiles 515
13.1 Nonwovens for upholstery material 515
13.2 Nonwovens for floorcoverings 517
13.3 Nonwoven fabrics for wallcoverings 519
13.4 Nonwoven fabrics as furnishing fabrics 520
13.5 Tufting substrate 520
14 Nonwovens for apparel 523
14.1 Nonwoven interlinings 523
14.1.1 Introduction 523
14.1.2 History of nonwoven interlinings 523
14.1.3 Functions of nonwoven interlinings 524
14.1.3.1 Interlining fabric for shaping and support 524
14.1.3.2 Nonwoven interlining for stabilizing and/or stiffening 525
14.1.3.3 Nonwoven interlinings for providing bulk 525
14.1.4 Properties of nonwoven interlinings 525
14.1.5 Functional elements of nonwoven interlinings 527
14.1.6 Outlook 528
14.2 Nonwovens for protective clothing 528
14.3 Nonwoven support materials for footwear 536
15 Nonwovens for technical applications 545
15.1 Insulation 545
15.1.1 Fire, heat, sound 545
15.1.2 Electrical insulation 554
15.2 Filtration 557
15.2.1 Dry filtration 560
15.2.1.1 General 560
15.2.1.2 Functional requirements properties 562
15.2.1.3 Surface filters 563
15.2.1.4 Depth filters 568
15.2.2 Liquid filtration 570
15.2.2.1 Liquid filters based on nonwovens 572
15.2.2.2 Variables in design of liquid filters 573
15.3 Building and construction industry 576
15.3.1 Geononwovens 576
15.3.1.1 Functions and requirements 578
15.3.1.2 Selected examples of the uses of nonwovens 581
15.3.1.3 Outlook 584
15.3.2 Bituminous roofing membranes 586
15.3.2.1 Introduction 586
15.3.2.2 Market overview 587
15.3.2.3 The bituminization of polyester nonwovens 588
15.3.2.4 The end use requirements of membranes with polyester inlay 590
15.3.2.5 Trends and developments 592
15.4 Agriculture 593
15.4.1 Introduction 593
15.4.2 Requirements to be met by agricultural nonwovens 594
15.4.3 Technological processes 595
15.4.4 Application 595
15.4.5 Market trends 597
15.5 The motor vehicle industry 598
15.5.1 The market 598
15.5.2 The car industry 599
15.5.2.1 Required characteristics 601
15.5.2.2 Acoustic and thermal insulation – inside the car 605
15.5.2.3 Acoustic and thermal insulation – the engine housing 607
15.5.2.4 Covering materials – interior of the car 607
15.5.2.5 Nonwovens for seat cushioning and laminated nonwovens 610
15.5.2.6 Automotive filter fabrics 612
15.5.2.7 Nonwovens as backing substrates, microfibre webs and other nonwovens 615
15.5.3 The aircraft, shipbuilding and railways industries 616
15.5.4 Outlook 617
15.6 Papermaking fabrics 617
16 Re-utilization of nonwovens 629
16.1 Waste from the production of nonwovens 629
16.1.1 Measures to reduce waste 630
16.2 Used waste of nonwoven materials 630
16.2.1 Disposables 630
16.2.2 Long-life products 631
16.3 Utilization of nonwoven waste 631
16.3.1 Mechanical processes to recover fibres 631
16.3.2 Re-granulation 631
16.3.3 Production of textile chips and their application 632
16.3.4 Processing nonwoven waste on KEMAFIL machines 632
16.3.5 Re-use of nonwoven waste 633

Part VI Regulations to be observed and processes to test raw materials and nonwoven products
17 General priciples 637
17.1 Sampling and statistics 637
17.2 Testing climate 638
17.3 Standards and specifications 638
18 Testing processes 661
18.1 Raw materials for nonwovens 661
18.1.1 Fibres 661
18.1.2 Granulates 668
18.1.3 Binders 669
18.2 Nonwovens 670
18.2.1 Textile-physical tests 670
18.2.2 Fastness testing 681
18.2.3 Testing of burning behaviour 687
18.2.4 Testing of the behaviour during laundering/dry cleaning 694
18.2.5 Human ecological tests 694
18.3 Test processes relating to end-use 696
18.3.1 Hygiene and medical products 696
18.3.2 Cleaning cloths and household products 697
18.3.3 Household textiles 698
18.3.4 Protective clothing 699
18.3.5 Filter fabrics 703
18.3.6 Geononwovens 708
19 Quality surveillance systems and quality assurance systems 717
20 Coming development in nonwovens industry 727
Index of names, companies, organizations, and products 731
Subject index 737