Contents
1. Introduction 1
1.1 Testing Methods (Sources of Testing Standards) 1
1.2 Selection of Samples for Testing 2
1.3 Sampling for Textile Testing 3
1.4 Fibre Sampling Techniques 3
1.5 Yarn Sampling Techniques 7
1.6 Fabric Sampling Techniques 8
1.7 Standard Atmosphere for Testing 8
1.8 Measurement of Moisture Regain 11
2. Fibre Testing 15
2.1 Fibre Length Measurement 15
2.2 Fibre Fineness Measurement 18
2.3 Cotton Maturity Measurement 21
2.4 Fibre Strength Measurement 23
2.5 Determination of Trash and Lint in Cotton 28
2.6 High Volume Instrument (HVI) 31
3. Yarn Testing 34
3.1 Yarn Numbering System (Count) 34
3.2 Determination of Yarn Count 37
3.3 Determination of Yarn Strength 38
3.4 Determination of Yarn Twist 43
3.5 Measurement of Yarn Evenness 49
3.6 Yarn Faults Classification 55
3.7 Measurement of Yarn Hairiness 57
4. Fabric Testing 60
4.1 Fabric Particulars – length, width, crimp, weight, cover factor 60
4.2 Fabric Strength – tensile strength tester, tearing strength tester, hydraulic bursting strength tester 65
4.3 Fabric Abrasion – Martindale abrasion tester 70
4.4 Fabric Pilling – I C I Pill box tester 72
4.5 Fabric drape –Measurement by Drape meter 73
4.6 Fabric Stiffness – Shirley stiffness tester 75
4.7 Fabric crease resistance and crease recovery-measurement of crease recovery 77
4.8 Fabric permeability – Shirley air permeability tester, fabric permeability to water, Bundesmann tester 78
4.9 Colour Fastness to Crocking, Perspiration, Sunlight, Laundering, Dry Cleaning, Hot Pressing 82
4.10 Colour Matching – Colour Matching Cabinets, Computer Colour Matching System 94
4.11 Objective Evaluation of Fabric Hand by KES and FAST Systems 98
5. Testing for Export Market 105
5.1 Testing based on customer requirements 105
5.2 Textile Safety Testing 107
5.3 Chemicals – heavy metals, phthalates, 108
5.4 Flammability – textiles, general wearing apparel and children’s sleepwear 110
5.5 Labelling – fibre, fur and faux fur, care instructions, stuffed articles (law labels) and country of origin 113
5.6 Mechanical hazards – drawstrings, small parts and sharp points and edges 114
6. Accreditation of Textile Testing Laboratory 118
6.1 Terminology 118
6.2 ISO/IEC 17025 118
6.3 National Accreditation Board for Laboratories (NABL) 120
Preface
Textile can be a fascinating term to mankind because of aspects such as colour, texture, design and comfort involved in its usage. The use of textiles by humans began with the identification of fibre, which dates back to prehistoric times. Such textiles are available in different forms for various end-uses like apparel, home textiles, and technical textiles. Here comes the necessity for testing of these textiles so as to ensure the quality of the product. Testing can be carried out at different stages, beginning from the raw material – fibre, and the subsequent intermediaries such as yarn, fabric – grey and processed stages, and finally, the garment.
Testing needs to be carried out in a well-organized manner since test results are used for evaluating product or fabric quality. Hence, given the importance of testing, various testing methods and procedures are standardized by organizations such as ISO, AATCC, ASTM, BSI, DIN, ANSI, and so on. The testing standards set by these institutions are unique and developed after careful research. It is crucial to understand the importance and necessity of textile testing. It is necessary that aspiring professionals and readers of this book understand the implications of terminologies such as calibration, reliability, repeatability and traceability, as they represent key criteria, parameters, and deliverables expected to be achieved via testing.
The aim of this book is to give specific information about the various procedures involved in textile testing in order for learners to gain knowledge about practical approaches utilized in textile testing. The standard atmosphere for testing, influence of moisture on properties of textiles, sampling methods’ importance as well as conditioning of sample before testing, testing procedures and, finally, the evaluation of results are explained.
This book is divided into six parts: First, introduction to textile testing with the sources of testing standards, sampling for testing, moisture and its relation with textiles; second, fibre testing; third, yarn testing; fourth, fabric testing; fifth, testing for export market; and sixth, accreditation of textile testing laboratory. Each chapter is self-explanatory, and on the whole, the book is a complete guide to textile testing.
I feel honoured to author this book, which is a collection of my experiences in textile testing, and to publish this with Woodhead Publishing India, a leading and eminent publisher in textile technology. My sincere thanks to Ms. Harpreet Kaur for her consistent efforts towards this publication. Above all, I thank Lord Almighty, my family and colleagues. I hope the book is informative and useful to the readers.
Amutha, K.