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Sadhan Chandra Ray

WOODHEAD PUBLISHING INDIA PVT LTDNew Delhi ● Cambridge ● Oxford ● Philadelphia

Published by Woodhead Publishing India Pvt. Ltd.Woodhead Publishing India Pvt. Ltd., G-2, Vardaan House, 7/28, Ansari RoadDaryaganj, New Delhi – 110002, Indiawww.woodheadpublishingindia.com

Woodhead Publishing Limited, 80 High Street, Sawston, Cambridge,CB22 3HJ UK

Woodhead Publishing USA 1518 Walnut Street, Suite1100, Philadelphia

www.woodheadpublishing.com

First published 2011, Woodhead Publishing India Pvt. Ltd.© Woodhead Publishing India Pvt. Ltd., 2012

This book contains information obtained from authentic and highly regardedsources. Reprinted material is quoted with permission. Reasonable efforts havebeen made to publish reliable data and information, but the authors and thepublishers cannot assume responsibility for the validity of all materials. Neitherthe authors nor the publishers, nor anyone else associated with this publication,shall be liable for any loss, damage or liability directly or indirectly caused oralleged to be caused by this book.Neither this book nor any part may be reproduced or transmitted in anyform or by any means, electronic or mechanical, including photocopying,microfilming and recording, or by any information storage or retrieval system,without permission in writing from Woodhead Publishing India Pvt. Ltd.The consent of Woodhead Publishing India Pvt. Ltd. does not extend tocopying for general distribution, for promotion, for creating new works, or forresale. Specific permission must be obtained in writing from WoodheadPublishing India Pvt. Ltd. for such copying.

Trademark notice: Product or corporate names may be trademarks or registeredtrademarks, and are used only for identification and explanation, without intentto infringe.

Woodhead Publishing India Pvt. Ltd. ISBN: 978-93-80308-16-6Woodhead Publishing Ltd. ISBN: 978 0 85709 108 6

Typeset by Sunshine Graphics, New DelhiPrinted and bound by Replika Press, New Delhi

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The knitting technology has been playing a very vital role in our life stylesince 1000 B.C. It not only produces fabrics and shaped garments forapparel and household purposes but also for various technical endapplications. Knowledge developed in the past, particularly in the last 50years in the field of knitting technology has contributed significantly tothe developments of state-of-the-art machinery on one hand and highlysophisticated and specialised textile products on the other. The basicprinciples of knitting technology as well as the recent developments inknitting are now-a-days included in the syllabi of the textile relatedundergraduate and postgraduate courses all over the country.

Prof. (Dr.) Sadhan Chandra Ray has written a textbook on“Fundamentals and Advances in Knitting Technology” to cater to the needof the students, teachers and professionals dealing with knitting technology.I appreciate the efforts of Prof. Ray for precisely covering the variousaspects of knitting technology in his book and Woodhead Publishing IndiaPvt. Ltd. Delhi for publishing the book. Suggestions are invited from thereaders for the improvement of the book in future.

Kolkata Prof. (Dr.) Dhrubajyoti ChattopadhyayAugust, 2011 Pro-Vice Chancellor (Academic)

University of Calcutta

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Clothing is one of our basic needs in life. The second most importanttechnique of manufacturing either clothing or clothing material is theknitting. Apparently, knitting is a very simple technique of making fabricor clothing, but it has complexity too. The more we study and the more weresearch on knitting, more and more mysteries of knitting are beingunveiled and we become more confident to control the technology ofknitting for producing from simpler to complex fabrics for diversifiedapplications in addition to traditional apparels even at a very high speed.Moreover, knowledge is now recognized as key input for future prosperityof knitting like other production techniques. During my long teachingexperience I always have felt the need for a suitable text book on knittingtechnology encompassing together all scientific information available inother books and journals at one place in a form that is lucid and easilycomprehensible to students and researchers. So the basic aim of writingthis book was to precisely combine the fundamental principles of knittingand related developments. It is hoped that this publication will fulfill theneed for an updated comprehensive publication which remained overduesince long.

The book introduces the basic concepts of knitting to a student with noexposure of knitting as well as the aspects of knitting science to apostgraduate student or researcher for better understanding the knittingtechnology and gaining an insight in to the mechanics of loop formationin knitting. Emphasis has also been given on recent developments andcomplicated things in knitting. Naturally, a number of ideas from previousbooks and journals have been gained on this subject to enrich the presentbook. I am indebted to all these authors.

Presently, knitting technology has been included in the syllabi of textiletechnology and allied courses in various undergraduate and postgraduatedisciplines. Keeping in view the above mentioned requirements, I haveendeavoured to bring out the present textbook based on my experience ofteaching and research in this particular branch of textiles. I have attemptedto incorporate the following notable features in the text like basics of weftand warp knitting, production of different knitted structures, latestdevelopments in knitting (machine, process and products), knitting science,

mechanics of knitting, knitting related calculations, traditional andobjective measurements of knitted fabrics, concept of green business inknitting, etc. For easy comprehension, the text has been supplemented byillustrations, tables and photographs wherever possible as well as abibliography at the end. The book is intended for a wide spectrum ofreaders, including students, researchers and academics, as well asprofessionals in the clothing and textile industries.

I have personally gathered all the information, arranged those in aparticular sequence, typed the manuscript, prepared all the figures excepta few and repeatedly checked the whole matter in order to achieve goodquality with minimum errors. However, all the readers are requested tosuggest necessary corrections and modifications for upgrading the qualityof the book in future publication.

Finally, I would like to express my sincere gratitude to my numerousteachers, students, friends, colleagues, well wishers and my familymembers who have contributed directly or indirectly by way of theirinspiration, constructive suggestion and useful discussion for writing thisbook.

Prof. Sadhan Chandra RayDepartment of Jute and Fibre Technology

Institute of Jute TechnologyUniversity of Calcutta

35, Ballygunge Circular RoadKolkata 700019

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Foreword vPreface vii

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1.1 Introduction to textile fabric 11.2 Introduction to knitting 21.3 History of knitting 21.4 Principle of hand knitting 31.5 Glimpses of knitting 41.6 Advantages of knitting 61.7 Reasons for the growth of knitting 71.8 Indian knitting industry 81.9 Comparison between weaving and knitting 10

References 11

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2.1 Classification of knitting 122.2 Classification of weft knitting machines 132.3 Classification of warp knitting machines 142.4 Comparison between weft knitting and warp knitting 17

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3.1 Introduction 193.2 Types of needles 193.3 Latch needle 203.4 Bearded needle 213.5 Compound or bi-partite needle 223.6 Manufacturing and specifications of latch needle 223.7 Sinker 243.8 Knitting cam system 273.9 Knitting action of the latch needle 303.10 Knitting action of the bearded needle 31

References 33

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4.1 Machine pitch and gauge 344.2 Loop 344.3 Face loop and back (reverse) loop 354.4 Single-faced structures and double-faced structures 364.5 Single jersey and double jersey fabrics 374.6 Courses, wales and stitch density 374.7 Loop length and course length 384.8 Different situations in loop formation 384.9 Stitch notation 394.10 Held loop 404.11 Tucking and tuck loop 404.12 Floating and float Loop (or missing and miss loop) 414.13 Drop or press-off stitch 424.14 Timing of knitting in circular double jersey machine 43

Reference 43

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5.1 Introduction to basic weft-knitted structures 445.2 Single jersey and double jersey knitting 445.3 Features of plain (single jersey) knitting (machine, process

and structure) 465.4 Features of rib knitting (machine, process and structure) 485.5 Features of interlock knitting (machine, process and structure) 495.6 Features of purl knitting (machine, process and structure) 505.7 Comparison between rib and interlock knitting 515.8 Comparison between rib and purl Knitting 515.9 Comparison of basic weft-knitted structures 515.10 Instability of plain loop 525.11 Some popular extended basic double jersey structures 55

References 55

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6.1 Relative technology with latch needle 566.2 Plating 586.3 Laying-in and inlaid structure 606.4 Fair isle technique 606.5 Fleecy fabric knitting 616.6 High pile or sliver knitted fabric production 626.7 Plush or terry fabric production 626.8 Yarn changer device or striper 646.9 Linking 65

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6.10 Loop transfer 656.11 Welt formation 666.12 Shaping during knitting 68

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7.1 Knitting machine 697.2 Frame 717.3 Drive 717.4 Creel 727.5 Tensioner 737.6 Guides 757.7 Feed plate 757.8 Methods of yarn feeding 767.9 Principles of yarn feeding 777.10 Number of feeders and feeder density 797.11 Stop motions 807.12 Take-down mechanism 817.13 Fabric spreader or stretcher board 827.14 Open width cloth winding 837.15 Sinkerless knitting machine 857.16 Speed factor 85

References 85

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8.1 Ornamentation of knitted structures 868.2 Horizontal striping 878.3 Intersia 878.4 Plating 898.5 Individual needle selection 898.6 Selection of pattern mechanism 978.7 Some special knitted designs/structures 97

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9.1 Introduction 1019.2 Types of flat bed machines 1019.3 Range of machine gauge and width 1029.4 Simple V-bed rib machines 1039.5 Knitting cam system 1069.6 Double cam systems 1089.7 Yarn tensioner and storage feeder 1099.8 Fabric take-down 1109.9 Loop transfer 110

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9.10 Racked structures 1129.11 Knitting of circular fabrics 1139.12 Mechanically controlled jacquard knitting 1149.13 C.M.S. machines 115

References 116

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10.1 Objectives of studying knitting science 11710.2 Fields of study 11710.3 Importance of knitted loop length and loop shape 11810.4 Loop length 11810.5 Robbing back 12110.6 Parameters of a knitted fabric 12210.7 Constants of a knitted fabric 12210.8 Some useful relations 12510.9 Relation between properties and geometry of a loop 12610.10 Geometry of weft knitted loop 12710.11 Tightness factor of knitted fabrics 12910.12 Relaxation of knitted fabrics 13110.13 Prediction of finished weight and shrinkage of cotton 131

knits – The Starfish ProjectReferences 132

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11.1 Introduction 13411.2 Measurement of loop length 13511.3 Control of loop length 13511.4 Important check points in knitting 13611.5 Faults in knitted fabrics 13711.6 Spirality in knitted structures 13911.7 Relationship between yarn properties and knitted fabric

qualities 14111.8 Pre-requisites for faultless production in knitting 14111.9 Main factors affecting the dimensional properties of knitted

fabrics/garments 14211.10 Online quality control 142

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12.1 Introduction 14412.2 Types of warp knitting machines 14512.3 Comparison between Tricot and Raschel type warp knitting

machines 145

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12.4 Knitting elements 14712.5 Warp beams 150

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13.1 Needle bar movement 15113.2 Guide bar movements 15113.3 Lapping diagram 15313.4 Tricot machine knitting cycle with bearded needle 15513.5 Raschel machine knitting cycle with latch needle 15613.6 Fabric take-down 15713.7 Warp let-off 15813.8 Patterning mechanisms 15913.9 Displacement of various knitting elements during loop 162

formation

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14.1 Introduction 16514.2 Types of stitches and structures 16614.3 Laying-in 16614.4 Co-We-Nit 16714.5 Full width weft insertion 16814.6 Milanese fabrics and machines 16914.7 Multi-axial knitting 17114.8 A few popular warp knit structures 17214.9 Warp knitted nets 17514.10 Common products of warp knitting machines 177

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15.1 Introduction 17915.2 Double needle bar Tricot machine 18015.3 Double needle bar Raschel machine 18115.4 Pile fabrics on double needle bar machine 18215.5 Tubular and branched fabrics on double needle bar machine 183

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16.1 Structural parameters of warp knitted fabrics 18516.2 Run-in per rack 18616.3 Yarn to fabric ratio 18616.4 Tightness factor of warp knitted fabrics 18716.5 Loop length and loop model of warp knitted cell 18716.6 Standardization of chain link and machine gauge 18816.7 Yarn count and machine gauge 188

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16.8 Grey specification of warp knitted fabric 18816.9 Fabric specifications 189

References 190

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17.1 Introduction 19117.2 Developments in flat bed weft knitting 19217.3 Developments in circular bed weft knitting 19317.4 Developments in warp knitting 19417.5 Technical textiles – the new product range in knitting 19517.6 Cut resistant gloves for food processing 19517.7 Concept of green bags and their knitting 197

References 198

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18.1 Yarn 19918.2 Types of yarn 19918.3 Important yarn characteristics/parameters 19918.4 Yarn count or number 20118.5 Conversion of count in one system to other system 20218.6 Count of plied or folded yarns 20218.7 Yarn count and yarn diameter 20218.8 Importance of yarn count 20318.9 Yarn composition 20318.10 Fibre wise end products 20518.11 Selection of yarns for knitting 20518.12 Knitting of textured yarns 20618.13 Scope of lycra yarn in knitting 20718.14 Scope of jute yarn in knitting 20818.15 Quality of cotton yarns used in circular weft knitting 20918.16 Relationship between machine gauge and yarn count 21018.17 Yarn package 211

References 212

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19.1 Merits of electronic elements and devices 21319.2 Fields of applications of electronics in knitting 21319.3 Computer-aided designing and manufacturing 21419.4 Computer-aided knitted fabric design 21519.5 Types of CAD for knitting and other peripherals 21719.6 Some of the exclusive features of standard software 21819.7 Computer-aided manufacturing of knitted fabrics (CAM) 219

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19.8 Data management system in electronic jacquard 21919.9 Knitting machine with built-in computer 22119.10 Design studio 221

References 223

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20.1 Introduction 22420.2 Yarn tensioner 22420.3 Yarn tension in knitting 22620.4 Measurement of yarn tension 22820.5 Measurement of coefficient of yarn to needle and yarn to 235

yarn frictionReferences 237

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21.1 Introduction 23821.2 Geometry of knitting zone 23921.3 Experimental studies on single jersey knitting 24321.4 Experimental studies on double jersey knitting 25021.5 Modeling of loop formation systems 256

References 260

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22.1 Introduction 26222.2 Warp knitted cell (loop) model 26322.3 The three-dimensional analysis of the loop’s picture 26622.4 Warp tension during loop formation 26822.5 Yarn tension and oscillation in the process of warp knitting 26922.6 Robbing back 27222.7 Influence of loop position on warp knitted structure 272

References 273

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23.1 Basics of calculations 27423.2 Examples of knitting related calculations 276

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24.1 Introduction 28324.2 Knitted spacer fabrics 28424.3 Production of spacer fabric in weft knitting 285

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24.4 Production of spacer fabric in warp knitting 28724.5 Common advantages of 3-dimensionally knited spacer fabrics 29024.6 Types of testing performed for spacer fabrics 29024.7 Warp knitted spacer fabric (WKSF) and its characteristics 291

References 292

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25.1 Textiles and garment industry 29325.2 Fabrics and garments 29425.3 Fabric characteristics 29525.4 Sourcing of fabrics for garments 29525.5 Trimmings 29725.6 Knitting and knitted fabrics for garments 29825.7 Shaping during knitting in garment length machine 29925.8 Garment manufacturing in knitting 30225.9 Concept of “Shima Seiki Whole Garment” 30625.10 Circular hosiery knitting 30725.11 Garmenting in warp knitting 31225.12 Potential benefits of seamless garment knitting 314

References 315

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26.1 Purpose of analysis 31626.2 Tools, equipments and materials for analysis 31626.3 Determination of technical face side and back side 31726.4 Parameters to be obtained during analysis of knitted fabrics 31826.5 Testing of knitted fabrics 32026.6 Traditional testing of knitted fabrics 32026.7 Low stress mechanical properties of fabrics 321

References 325

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27.1 Introduction to medical textiles 32627.2 Important functions of medical textiles 32727.3 Wound care management 32727.4 Human body parts made of textile materials 32727.5 Advantages of knitting in the production of medical textiles 32727.6 Types of machines used 32827.7 A few knitted medical textiles 32827.8 Latest trend in medical textiles 329

References 329

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28.1 Concept and importance of green business 33028.2 Environmental management 33128.3 Green business in knitting and knitwear industries 33228.4 Suggestions for maintaining green environment 334

References 335

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Abstract: Textile fabric is defined as two dimensional plane-likestructure made of textile materials, having reasonable strength,elongation, flexibility, etc., used for different applications,particularly for apparels. Knitting is the second most populartechnique of fabric or garment formation by inter-looping one or oneset of yarns, and its share in fabric production is about 20%. Inknitting continuous length of yarn is converted into verticallyintermeshed loops either by hand or by machine. So in order to stepinto the subject of knitting, the history of knitting technology, thegrowth of knitting industry in India and the comparison of knittingand weaving have been highlighted in this chapter.

Key words: knitting, weft knitting, warp knitting, loop, fabric,needle.

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The human beings, impelled by nature and compelled by necessity, soughta better kind of material than barks or leaves of trees and hides of animalsto protect their bodies from inclemencies of variable weather as well as toprotect the sex organs from the magical influence, which resulted theinvention of the technology of manufacturing textile fabric/clothing. Theavailable documents of human civilization that took place in different partsof the world confirmed that invention of the technology of manufacturingtextile fabric (clothing) happened about 7000 years ago. Textile fabric isdefined as a two dimensional (2D) plane-like structure (may be woven,knitted, nonwoven, braided, etc.) made of textile materials (fibre or yarnor their combination) having reasonable strength, elongation, flexibility,etc., used for different applications, particularly for apparels. Recently,fabrics are also made in three dimensions (3D) and widely used in technicalapplications including medical textiles in the form of artificial cardio-vascular tube as well as different joints and tissues of the human body.Weaving, the technology of producing fabric by interlacing two sets ofthreads (warp andweft), is the oldest technique of fabric formation, andits share in total fabric production is about 70%. Knitting, the second old

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