Effect of Pretreatment on the Smoothness Behaviour of Cotton Fabric

Nidhi Sisodia*, M.S. Parmar, Effect of Pretreatment on the Smoothness Saurbh Jain Behaviour of Cotton Fabric DOI: 10.5604/01.3001.0013.2901

Northern India Textile Research Abstract Association Ghaziabad, Before dyeing, woven cotton fabrics have been passed through different pretreatments like Ghaziabad, India, desizing, scouring, bleaching and mercerising to enhance quality. In every treatment cotton * e-mail: [email protected] fabric is treated with different chemicals and mechanical processes. After these treatments, the feel of the fabric has been changed. The change in feel or in terms of the hand value of treated fabrics were analysed by determining the bending length, crease recovery angle, SEM, FTIR, surface roughness and smoothness properties. Other physical properties viz. the tear and tensile strength were also evaluated. Fabric surface roughness and smoothness were determined using the Kawabata Evaluation System (KES) and digital image processing method. Using MATLAB software, digital image processing techniques were used to evaluate the roughness index. The study revealed that the pretreatment process alters the fabric surface. Statistical analysis (ANOVA) was carried out using SPSS software in order to establish the relationship between the pretreatment process effect on the bending length, smoothness and crease recovery angle. Key words: dyeing, pretreatment, desizing, scouring, bleaching, statical analysis.

Introduction purposes a commercial desizing enzyme Tegewa test drop test method, spray test was used. method, and whiteness index. At the present time the garment indus- try and fabric producers are confronting Pretreatment a great deal of issues with respect to the Analysis of fabric samples The cotton fabric was pretreated by de- hand feel of material. There is no stand- sizing, scouring, bleaching & merceri- The cotton fabrics (woven) were pre- ard method available using which the sation as per the sequence given in Fig- treated (singed, desizing, scouring, smoothness of fabric can be measured. ure 1 using a standard recipe, shown in bleaching and mercerisation) as per the Just subjective evaluation is completed to Table 1. standard recipe. The test standards used judge the feel of the fabric. When a fabric for the study are given in Table 1. or garment of clothing is purchased, the Singeing and desizing consumer constantly attempts to pick it based on his own evaluation technique Singeing removed loose and unwant- for a specific end use [1]. ed fibres from the fabric surface to get a smooth surface. Enzymatic desizing Grey fabric The surface of any wearable material was done after singeing. can be modified by chemical or mechanical procedures. Fabric smoothness is Scouring specifically related to the fabric surface Desized fabric was treated with alkaline friction. Fabric surface smoothness be- solution to scour it. This process im- Singeing haviour depends upon the yarn qualities, proved the absorbency of the fabric by weave points of interest, and finally on removing impurities. the sort of chemical treatment. The use of chemical treatment makes a fabric Bleaching Desizing rough or smooth. Chemical or mechani- Woven cotton fabric was bleached using cal treatment modifies the surface prop- hydrogen peroxide to remove the natural erties of fabric. The chemical treatment colouring [3]. of cotton to alter the physical properties of fibres without changing their shape is Mercerisation Scouring a common practice in the textile indus- Chain mercerisation was used to merce- try [2]. rise the cotton fabric. The concentration of sodium hydroxide was 52° Tw [4]. Material Bleaching In this study plain weave (1/1) cotton This work centered around the treatment fabric of 128 g/m2 mass and 120 and of cotton with various pretreatments: 70 ends and picks per inch, respective- the cotton texture was successively pre- ly, was procured from surya processors treated as shown in Figure 1, utilising in the grey stage. All the chemicals, like the standard formula given in Table 1. Mercerization sodium hydroxide, sodium carbonate, After every pretreatment process the hydrogen peroxide etc., used in the study treated sample was tested for its qual- were of commercial grade. For desizing ity using standard test methods viz. the Figure 1. Flow chart of process sequence.

Sisodia N, Parmar MS, Jain S. Effect of Pretreatment on the Smoothness Behaviour of Cotton Fabric. 47 FIBRES & TEXTILES in Eastern Europe 2019; 27, 5(137): 47-52. DOI: 10.5604/01.3001.0013.2901 Table 1. Test standard. Statistical analysis

S. no. Test name Test standard Experimental data were analysed using 1 GSM IS 1964:2001 SPSS (version 20). One-way ANOVA and 2 Thread density (EPI/PPI) IS:1963-1981(reaffirmed:2004 ) Multivariate Anova were used to compare 3 Count (IS 3442:1980) means. The null hypothesis (Ho) is that 4 Crease recovery IS 4681-1968 there is no relationship between the types 5 Bending length IS6490-1971 of processing treatment of the fabric and 6 Tear strength ISO-13937-1 the coefficient of friction (smoothness), 7 Tensile strength ISO 13934-1 bending length and crease recovery when using a digital image processing system. In the alternative hypothesis, there is a re- The change in fabric surface roughness face plot in Matlab. The colour of indi- lationship between the types of processing or smoothness after the pretreatment pro- vidual pixels was plotted as the height treatment of the fabric and the coefficient cess was determined using the ‘Digital in the graph. As there is a difference of friction (smoothness), bending length Image Processing (DIP)’ method using between the colour of different regions and crease recovery of fabrics when us- MATLAB software and the Kawabata of the fabric, this causes a variation in ing a digital image processing system. Ho Evaluation System (KES-F), a scanning the height of the plot. This difference is will be rejected when the p-value turns electron microscope from 30 Kv = JEOL used to determine the surface roughness. out to be less than a pre-determined sig- (JAPAN) model JSM-6360. These meth- An appropriate computer programme nificance level, i.e. 0.05. ods are described below. was written with due consideration of the various parameters of the three dimen- Result and discussion Digital image processing method sional surface plot of the scanned fabric The DIP method is based on the theory of images, and simulation was finished uti- The physical properties of fabric like the surface height variation measurement. In lising Matlab programming to obtain the mass, ends per inch/picks per inch, bend- accordance with this method, fabric sam- fabric surface roughness index [6]. ing length, crease recovery angle and ples were scanned using a 600 dpi digital tensile strength along with the surface smoothness in terms of the coefficient of image processing scanner [5]. After scan- Kawabata evaluation system friction (MIU) and surface roughness in ning, the images obtained were cropped Coefficients of friction (MIU) were- de terms of the peak height, using a digital so as to have a uniform and regular fig- termined using the Kawabata system. image processing system for all 6 fabrics ure. Using Matlab software, the simula- MIU was determined in the warp and treated along with gray fabric, are as- tion and surface roughness were plotted. weft directions for fabric samples on the sessed in Tables 2 and 3. The images obtained were first inverted sides that would be in contact with the so that the lighter areas represented the skin during wearing [7]. From the table it is clear that the mass of densely populated part of the fabric and the samples varies from 118 to 128 g/m2. the dark parts – the sparsely populated re- The frictional coefficient MIU is calcu- The mass of the grey fabric (128 g/m2) gion [6]. The images were transformed to lated by averaging the output over the is found to be higher than the others gray scale and then loaded into Matlab. distance between 0 to 20 mm using an due to the presence of the sizing agent. To remove noise, Gaussian filters were integrator [8]. Ends/inch and picks/inch of the treated applied. The degree of smoothening was fabric samples i.e. samples having un- determined by the standard deviation of The frictional coefficient is defined as: dergone mercerisation treatments, were the Gaussian, which is generally taken found to be higher than those of the grey MIU = F/P as 5 [6]. A surface plot is three dimen- due to wet shrinkage during processing. sional, connecting a set of data points. Where F – frictional force, N, P – sensor The increase in ends/inch and picks/inch The images were then converted to a sur- load, N. also increase the tear strength of the treat-

Table 2. Physical properties of fabric.

Crease recovery Coefficient Tensile strength, N Tear strength, g Bending length, cm Sample Mass, Ends Picks angle of friction-Kawabata code g/m2 per cm per cm (warp + weft ) Warp Weft Warp Weft degree Warp Weft Warp Weft Grey 128 48 28.8 576 259 1138 569 106 2.45 1.75 0.15 0.152 Singed 124 48.8 28.8 560 270 1112 536 110 2.40 2.80 0.158 0.161 Desized 118 50.4 31.2 520 230 1150 720 140 1.58 1.46 0.167 0.171 Scoured 124 51.2 32 580 240 1064 676 144 1.55 1.42 0.156 0.158 Bleached 126 53.6 32.8 700 271 897 640 146 1.56 1.40 0.153 0.152 Mercerised 127 54.4 32 681 258 977 670 156 1.40 1.38 0.149 0.136

Table 3. Roughness index measured by DIP method.

Maximum decrease Fabric sample Grey Desized Scoured Bleached Mercerised in roughness index, % Maximum height of peaks 28 30 50 60 16 42%

48 FIBRES & TEXTILES in Eastern Europe 2019, Vol. 27, 5(137) 2 2 Pretreatment process vs mass, g/m PretreatmentPretreatment process vs vs ends/cm mass, &g/m picks/cm Pretreatment vs ends/cm & picks/cm Mass, g/m2 Mass, g/m2 Ends per cm Picks per cm Ends per cm Picks per cm 130 130 125 125 120 12060 60 40 40 115 11520 20 110 1100 0

Figure 2. Effect of pretreatment on GSM. FigureFigure 2. 3Effect. Effect of of pretreatment pretreatment on on GSM. EPI/PPI. Figure 3. Effect of pretreatment on EPI/PPI.

2 2 PretreatmentPretreatment process process vs mass, vs mass, g/m2 g/m 22 PretreatmentPretreatmentPretreatment process vs processprocess mass, vsg/mvs mass,mass,2 g/mg/m2 PretreatmentPretreatmentPretreatment vs ends/cm vs vsvs ends/cmends/cm ends/cm & picks/cm & & & picks/cmpicks/cm picks/cm Pretreatment process vs tensile strength PretreatmentPretreatmentPretreatmentPretreatment process process process vsvs tear mass,vsvs tensilemass,strength g/m strengthg/m PretreatmentPretreatmentPretreatmentPretreatment vs ends/cm vs vs ends/cm &vs tear picks/cm ends/cm strength & picks/cm & picks/cm Mass,Mass, Mass,g/m2 g/m2Mass,Mass, g/m2 g/m2 g/m2 Mass,Mass, g/m2 g/m2 Ends perEnds cmEndsEnds per per cmperPicks cm cmcm perPicks cmPicksPicksPicks per per per cm per cmcm cm Tensile strength, N Warp Tensile strength, N Weft TensileTear Strength, strength, gN Warp Warp TearTensile Strength, strength, g Weft N Weft Tear Strength,EndsEnds gper Warp percm cm TearPicks PicksStrength, per percm cmg Weft 130130130 130130 130Pretreatment130 process vs mass, g/m2 2 125125Pretreatment125Pretreatment125125 process process vs vs mass, mass, g/m g/m PretreatmentPretreatment vs vs ends/cm ends/cm & &picks/cm picks/cm 125125 Mass,Mass, g/m2 g/m2 120120 60 60 606060 Ends per cm Picks per cm 800 1201201500800120 6015006040 EndsEnds per per cm cm PicksPicks per per cm cm 600 1301201000600120 115 40 4010004040 400 115115130130400115 115 20 2040 40202020 200 115200115500110110 0 2050000 0 11011012512511000 0 2000 120110120110 600600 4040 115115 2020 110110 0 0

Figure 4. Effect of pretreatment on Tensile strength. FigureFigureFigure 2Figure.Figure Effect4. 5Effect. Effect of 22. .pretreatmentEffect Effectof of pretreatment pretreatment ofof pretreatmentpretreatment on GSM. on on Tensile on ontear GSM.GSM. strength. strength. Figure 3Figure. EffectFigureFigure 5of . 3 3Effectpretreatment..EffectEffect of ofof pretreatment pretreatmentpretreatment on EPI/PPI. onon EPI/PPI.tearEPI/PPI. strength. FigureFigureFigure 2. 2 .EffectEffect 2. Effect of of pretreatment pretreatment of pretreatment on on GSM. GSM. on GSM. FigureFigureFigure 3. 3 .EffectEffect 3. Effect of of pretreatment pretreatment of pretreatment on on EPI/PPI. EPI/PPI. on EPI/PPI. FigureFigure 2. Effect 2. Effect of pretreatment of pretreatment on GSM. on GSM. FigureFigure 3. Effect 3. Effect of pretreatment of pretreatment on EPI/PPI.on EPI/PPI. Pretreatment vs coeffecient of friction Effect of pretreatmentPretreatment on vs crease coeffecient recovery of friction angle Effect of pretreatment on crease recovery angle Coefficient of friction-kawabata Warp PretreatmentCoefficientPretreatmentPretreatment process(warp of friction+ vs weft)process process tensile- kawabatadegree vs strengthvs tensiletensile Warp strength strength PretreatmentPretreatmentPretreatment vs(warp tear strength + weft) vs vs teartear degree strengthstrength Coefficient of friction-kawabata Weft PretreatmentPretreatmentCoefficient process of process friction vs tensile- kawabatavs tensile strength strengthWeft PretreatmentPretreatment vs tear vs tearstrength strength FigureFigureTensile 2. 2Effect. Effect strength,Tensile of ofpretreatment pretreatment N strength, Warp N on WarpTensile on GSM. GSM. strength, Tensile N strength, Weft N Weft FigureTearFigure Strength, 3. 3EffectTear.TearEffect g Strength, Strength, Warpof ofpretreatment pretreatment g Tearg WarpWarp Strength, on onTear TearEPI/PPI. EPI/PPI. g Strength,WeftStrength, g g WeftWeft BendingPretreatmentTensilePretreatment length, strength, cmprocess Warp process N Warpvs tensile vsBending tensileTensile strength length, strength strength, cm Weft N Weft BendingPretreatment length,Pretreatment cm Warp vs tear vs tear strengthBending strength length, cm Weft TensileTensile strength, strength, N Warp N Warp TensileTensile strength, strength, N Weft N Weft TearTear Strength, Strength, g Warp g WarpTearTear Strength, Strength, g Weft g Weft TensileTensile strength, strength, N Warp N Warp TensileTensile strength, strength, N Weft N Weft TearTear Strength, Strength, g Warp g WarpTearTear Strength, Strength, g Weft g Weft 800 800800 1500 15001500 6003 PretreatmentPretreatment600 process process vs vs tensile tensile strength strength 3 PretreatmentPretreatment vs vs tear tear strength strength 200 400200 600 1000 10001000 150 8001502800 400400 5001500Tear21500 Strength, g Warp Tear Strength, g Weft 600200800TensileTensile800600 200strength,200 strength, N NWarp Warp TensileTensile strength, strength, N NWeft Weft 10001500Tear10001500Tear500500 Strength, Strength, g Warpg Warp TearTear Strength, Strength, g Weftg Weft 100 40060001001600400 00 0 10001 00 50 20040040020050 5001000500 0 2000020000 5000 5000 8008000 0 150015000 0 600600 1000 400400 10001000 200200 500500 0 0 0 0 Figure 4Figure.FigureEffect of 44. .pretreatmentEffectEffect ofof pretreatmentpretreatment on Tensile on onstrength. Tensile Tensile strength.strength. Figure 5. EffectFigureFigure of 5 5pretreatment..EffectEffect ofof pretreatmentpretreatment on tear strength. onon teartear strength. strength. Pretreatment vs coeffecient of friction Effect of pretreatment on crease recovery angle Figure 6. Effect of pretreatment on coefficient of friction. FigureFigure 6. 7Effect. Effect of of pretreatment pretreatmentPretreatmentPretreatment on on coefficientvs vs bending coeffecientcoeffecient length.of friction.of of frictionfriction Figure 7EffectEffect. Effect of of pretreatmentpretreatmentof pretreatment on on creasecrease on bending recovery recovery length. angleangle FigureFigure 4. Effect 4.CoefficientEffect of pretreatment of pretreatmentof friction -onkawabata Tensile on Tensile Warp strength. strength. FigureFigure 5. Effect 5.(warpEffect of +pretreatment weft)of pretreatment degree on tear on tearstrength. strength. FigureFigure 4. Effect 4. Effect of pretreatment ofCoefficientCoefficient pretreatment of ofon frictionfriction Tensileon Tensile--kawabatakawabata strength. strength. Warp Warp FigureFigure 5. Effect 5. Effect of pretreatment of (warppretreatment(warp ++ weft)weft) on degree degreetearon tear strength. strength. Figure 4. EffectCoefficient of pretreatment of friction on-kawabata Tensile Weftstrength. Figure 5. Effect of pretreatment on tear strength. PretreatmentCoefficientPretreatmentCoefficient vs of of coeffecient frictionfriction vs coeffecient--kawabatakawabata of friction of Weft Weft friction BendingEffect length,Effect of cmpretreatment of Warp pretreatmentBending on crease on length, crease recovery cm recoveryWeft angle angle CoefficientCoefficientPretreatmentPretreatment of friction of friction vs-kawabata coeffecient vs- coeffecientkawabata Warp of Warpfriction of friction EffectEffectBendingBending of pretreatment of length, length, pretreatment(warp(warp cm cm+ Warpweft) Warp on + weft) crease ondegree creaseBending Bendingdegree recovery recovery length, length, angle cm cm angle Weft Weft Crease recovery angle Figure(WarpFigure +Weft 4. 4Effect. Effect Coefficient)Coefficient Degree ofCoefficient ofpretreatment pretreatment of of friction friction of friction on-kawabata- kawabataon Tensile -Tensilekawabata strength. Weft Warpstrength.Crease WeftWarp recovery angle (WarpFigureFigure +Weft 5. 5Effect .) EffectDegree of ofpretreatment(warp pretreatment(warp + weft) + weft) ondegree on teardegree tear strength. strength. CoefficientCoefficient of friction of friction-kawabata-kawabata Weft Weft 3 BendingBending length, length, cm Warp cm Warp BendingBending length, length, cm Weft cm Weft Crease recovery angle (Warp200 +Weft ) DegreePretreatmentPretreatment vs vs coeffecient coeffecient ofCrease offriction friction recovery angle (Warp Bending+WeftEffect3Bending3 of) length,Degree pretreatment length, cm Warpcm Warp on creaseBendingBending recovery length, length, angle cm Weftcm Weft 150 200200 2 EffectEffect of ofpretreatment pretreatment on on crease crease recovery recovery angle angle Coefficient150150Coefficient of offriction friction-kawabata-kawabata Warp Warp 22 (warp(warp + weft)+ weft) degree degree 100 100 1 50 Coefficient100Coefficient of offriction friction-kawabata-kawabata Weft Weft 3 311 2000200 5050 0 3 3 200 150200150200 20000 2BendingBending200 length, length, cm cm Warp Warp BendingBending length, length, cm cm Weft Weft 2 100150100150 1 12 1005010050 1 1 100 500 500 100 03 30 2002000 0 0 1501500 2 2 0 100100 0 1 5050 1 1 Grey Singed DesizedFigure 6.ScouredEffect of pretreatmentBleached on coefficientMercerisedGrey of friction.Singed DesizedFigure 7. EffectScoured of pretreatmentBleached on bendingMercerised length. FigureFigure0 0 66..EffectEffect ofof pretreatmentpretreatment onon coefficientcoefficient of of friction.friction. FigureFigure0 0 77..EffectEffect ofof pretreatmentpretreatment onon bendingbending length. length.

Crease recovery angle (Warp +Weft ) Degree FigureFigure 6. Effect 6. Effect of pretreatment of pretreatment on coefficient on coefficient of friction. Creaseof friction. recovery angleFigure (WarpFigure 7+Weft. Effect 7. )Effect Degree of pretreatment of pretreatment on bending on bending length. length. Sisodia N, Parmar MS Dr, Jain S. Effect of Pretreatment on the Smoothness Behaviour of CottonFigure SisodiaFabric.Figure 6N,. ParmarEffect 6. Effect MS of Dr, pretreatment of Jain pretreatment S. Effect of Pretreatmenton coefficienton coefficient on the of Smoothness friction.Crease of friction. Behaviourrecovery of angle Cotton35 Figure (WarpFabric. Figure +Weft 7. Effect 7 .) EffectDegree of pretreatment of pretreatment on bendingon bending length. length. 35 FIBRES & TEXTILES in Eastern Europe 2019; 27, 5(137): XX-XX. DOI: 10.5604/01.3001.0013.2901FIBRES & TEXTILES in Eastern Europe 2019; 27, 5(137):Crease XX-XX. recovery DOI: 10.5604/01.3001.0013.2901 angle (Warp +Weft ) Degree CreaseCrease recovery recovery angleangle (Warp(Warp +Weft +Weft ) ) DegreeDegree FigureFigure 6. 6 Effect. Effect of of pretreatment pretreatment on on coefficient coefficientCrease of ofCrease friction. friction. recovery recovery angle angle (WarpFigure (WarpFigure +Weft 7.+Weft 7 )Effect .DegreeEffect ) Degree of of pretreatment pretreatment on on bending bending length. length. FigureFigure 6. 6Effect. Effect of ofpretreatment pretreatment on on coefficient coefficientCrease of offriction. friction.recovery angle (WarpFigure Figure+Weft 7 ). 7EffectDegree. Effect of ofpretreatment pretreatment on on bending bending length. length. 200 Crease recovery angle (Warp +Weft ) Degree 200200 CreaseCrease recovery recovery angle angle (Warp (Warp +Weft +Weft ) Degree ) Degree CreaseCrease recovery recovery angle angle (Warp (Warp +Weft +Weft ) Degree ) Degree 100 CreaseCrease recovery recovery angle angle (Warp (Warp +Weft +Weft ) Degree ) Degree 100100 2000 200 Crease recovery angle (Warp +Weft ) Degree 200200 CreaseCrease recovery recovery angle angle (Warp (Warp +Weft +Weft ) Degree ) Degree 00 Grey Singed Desized Scoured Bleached Mercerised 100100 GreyGrey SingedSinged DesizedDesized ScouredScoured BleachedBleached MercerisedMercerised 100100 200200 Sisodia N, Parmar MS Dr,0 Jain S.0 Effect of Pretreatment on the Smoothness Behaviour of Cotton Fabric. 35 FIBRES & TEXTILESSisodia N, in ParmarEastern0 0 MS Europe Dr, Jain 2019; S. Effect27, 5(137): of Pretreatment XX-XX. DOI: on the10.5604/01.3001.0013.2901 Smoothness Behaviour of Cotton Fabric. Sisodia N,100 Parmar100 MS Dr, Jain S. Effect of PretreatmentGreyGrey on theSinged SmoothnessSinged BehaviourDesized Desizedof Cotton Fabric.Scoured ScouredBleachedBleachedMercerisedMercerised 3535 FIBRESFIBRES & & TEXTILES TEXTILES in in Eastern Eastern Europe Europe 2019; 2019;Grey 27, 27,Grey 5(137): 5(137): XX-XX. XX-XX.Singed DOI: SingedDOI: 10.5604/01.3001.0013.2901 10.5604/01.3001.0013.2901DesizedDesized Scoured Scoured BleachedBleachedMercerisedMercerised 0 0 SisodiaSisodia N, Parmar N, Parmar MS Dr, MS Jain Dr, S. Jain Effect S. Effectof Pretreatment of PretreatmentGrey onGrey the on Smoothness the SmoothnessSingedSinged Behaviour Behaviour of CottonDesizedDesized of Cotton Fabric. Fabric. Scoured Scoured BleachedBleached MercerisedMercerised 35 35 FIBRESSisodiaFIBRESSisodia &N, TEXTILES Parmar N, & ParmarTEXTILES MS in Dr, EasternMS Jain inDr, Eastern S.Jain Europe Effect S. EuropeEffect of2019; Pretreatment of 2019;27, Pretreatment 5(137): 27, on5(137): XX-XX. the on Smoothness theXX-XX. DOI: Smoothness DOI:10.5604/01.3001.0013.2901 Behaviour 10.5604/01.3001.0013.2901 Behaviour of Cotton of Cotton Fabric. Fabric. 35 35 FIBRESFIBRES & TEXTILES & TEXTILES in Eastern in Eastern Europe Europe 2019; 2019; 27, 5(137): 27, 5(137): XX-XX. XX-XX. DOI: DOI: 10.5604/01.3001.0013.2901 10.5604/01.3001.0013.2901 Figure 8. Effect of pretreatment on crease recovery angle. SisodiaSisodia N, N,Parmar Parmar MS MS Dr, Dr, Jain Jain S. EffectS. Effect of Pretreatmentof Pretreatment on onthe the Smoothness Smoothness Behaviour Behaviour of Cottonof Cotton Fabric. Fabric. 3535 FIBRES & TEXTILES in Eastern Europe 2019; 27, 5(137): XX-XX. 10.5604/01.3001.0013.2901 FIBRESFIBRESFIBRES & TEXTILES & TEXTILES& TEXTILES in Eastern in Easternin EuropeEastern Europe 2019, Europe Vol. 2019; 2019;27, 27, 5(137) 27, 5(137): 5(137): XX-XX. XX-XX. DOI: DOI: 10.5604/01.3001.0013.2901 10.5604/01.3001.0013.2901 49 Tensile Strength Tensile Strength The tensile strength of mercerised fabric samples increased due to the swelling of cotton fibres in the presence of The tensile strength of mercerised fabric samples increased due to the swelling of cotton fibres in the presence of alkali. The mercerisation process removes convolution and false twist (causing weak spots). Thus fibres acquire a alkali. The mercerisation process removes convolution and false twist (causing weak spots). Thus fibres acquire a more uniform cross section. As weak spots are removed, the strength of the fibre increases [4]. more uniform cross section. As weak spots are removed, the strength of the fibre increases [4].

Bending length: Values of the bending length of untreated and treated cotton fabrics are given in table 2 and Bending length: Values of the bending length of untreated and treated cotton fabrics are given in table 2 and figure 6 above. From these wefigure obtain 6 above. data of From the bendingthese we length obtain for data both of the bendingwarp and length weft fordirections both the of warpthe and weft directions of the cotton fabric, respectively. It iscotton evident fabric, from respectively. table 2 that It the is evidentbending from length table in both 2 that the the warp bending and weftlength directions in both the warp and weft directions is going to decrease from theis control going toto decreasethe mercerised from the sample. control Untreated to the mercerised fabric shows sample. the maximumUntreated bendinfabric showsg the maximum bending length (warp and weft), whichlength is periodically (warp and reduced weft), which after istreatment periodically such reduced as desizing, after scouring, treatment bleaching such as desizing, and scouring, bleaching and mercerisation. mercerisation.

Crease recovery: Values of Creasethe recovery recovery: angle Values of untreated of the andrecovery treated angle cotton of untreatedfabrics are and given treated in tablecotton 2 fabrics& are given in table 2 & figure 7 above. It is evident thatfigure the 7crease above. recovery It is evident angle that is going the crease to increase recovery from angle the iscontrol going toto theincrease mercerised from the control to the mercerised sample. Untreated fabric showssample. a minimum Untreated crease fabric recovery shows angle,a minimum which crease periodically recovery increases angle, which after desizing,periodically increases after desizing, scouring, bleaching and mercerisationscouring, treatment. bleaching and mercerisation treatment.

SEM analysis of woven cottonSEM fabric analysis of woven cotton fabric SEM images at 1000x magnificationSEM images are atgiven 1000x in magnificationfigures 8,9,10 are&11 given of grey in figuresand treated 8,9,10 samples. &11 of As grey the and treated samples. As the samples were treated with differentsamples chemicals, were treated there with are different some clear chemicals, differences there in arethe somerespective clear images.differences There in theis respective images. There is a clear difference in the respectivea clear chemical difference treatments in the respective for woven chemical cotton fabric.treatments Figures for woven8, 9, 10 cotton & 11 fabric.show SEM Figures 8, 9, 10 & 11 show SEM photographs of untreated, scoured,photographs bleached of anduntreated, mercerised scoured, cotton bleached fabrics. and When mercerised compared cotton to the fabrics. treated When fabrics compared to the treated fabrics (Fig 9 and Fig 10), the surface(Fig of 9 theand mercerised Fig 10), the fabric surface sample of the has mercerised a smooth fabricsurface, sample as shown has ain smooth the SEM surface, as shown in the SEM photograph (Fig 10). It is a wellphotograph known fact (Fig that 10). when It is cotton a well fabricknown is fact treated that withwhen alkali cotton under fabric tension is treated in order with toalkali under tension in order to achieve maximum fibre swelling,achieve the fibremaximum surface fibre becomes swelling, smoother[2]. the fibre surface becomes smoother[2].

ed fabric. On the other hand, the tensile strength of the mercerised fabric was found to be higher than that of the fabric treated with various pretreatments. Tensile strength The tensile strength of mercerised fabric samples increased due to the swelling of cotton fibres in the presence of alkali. The mercerisation process removes convolution and false twist (causing weak spots). Thus fibres acquire a more uniform Fig.8: SEM micrograph of untreatedFig.8:Figure SEM9. SEM micrograph micrograph of of untreated. untreated Fig.9: SEM Figure micrograph 10. SEM of micrograph scoured Fig.9: wovenSEMof scoured micrograph cotton cross fabric section.of scoured As weak woven spots cotton are removed, fabric woven cotton fabric woven cotton fabric woven cotton fabric woven cotton fabric. the strength of the fibre increases [4]. Fig.10: SEM micrograph of bleached samples Fig.11: Bending SEM length micrograph of mercerized sample Fig.10:Fig.10:Fig.10:Fig.10: SEM SEM SEM SEM micrograph micrograph micrograph micrograph of of of bleached ofbleached bleachedbleached samples samples samplessamples Fig.11: Fig.11: Fig.11:Fig.11:Values SEM SEM SEM SEM of micrographthe micrographmicrograph micrographbending length of of ofmercerized ofmercerized mercerizeduntreated sample samplesample sample and treated cotton fabrics are given in Ta- ble 2 and Figure 7 above. From these we Fabric surface peak height and roughness index obtain data of the bending length for both FabricFabricDigitalFabricFabric surface surface imagesurface surface peak processingpeak peak peak height height height height methodsand and andand roughness roughness roughnessroughness were used index index index to obtain surface plots thefor warp mercerised and weft directions and softener of the cottreated- fabric ton fabric, respectively. It is evident from DigitalDigitalsamples.DigitalDigital image image image Theimage processing plotsprocessing processing processing thus obtainedmethods methods methodsmethods arewere were were wereshown used used usedused into to Fig. toobtain obtain obtain 12. surface Itsurface surfaceissurface observed plots plots plotsplots forthat Tablefor forfor mercerised mercerisedthe mercerised2mercerised that scoured the bendingand andand and softener softener bleached lengthsoftener in treated treatedboth fabrictreated fabric samplefabricfabric fabric samples.samples.hassamples.samples. a higher The The The The plots plotsnumber plots plots thus thus thus thus ofobtained obtained peaksobtained obtained withare are areare shown showna shownshownhigher in in inFig. peakFig. Fig. 12. 12.height, 12. It It isItIt is isobservedis asobserved observedobserved shown that thatin thatthethat the Fig.warpthe the the scoured scoured 12(d)scouredand scoured weft and and anddirectionsand and (e),bleached bleachedbleached bleached also is going in fabric fabricTable fabricto sample sample sample3. sample This hashashas hasa a higher ahigher ahigher higher number number number number of of ofpeaks ofpeaks peakspeaks with with withwith a a higher aahigher higherhigher peak peak peak height, height, height, as as asasshown shown shownshown in in in in decreaseFig. Fig. Fig.Fig. 12(d) 12(d) 12(d) from12(d) and the andand and control (e), (e),(e), (e), also alsoto also the in in merce inTable Table Table- 3. 3.3. 3. This ThisThis This indicates that the surfaces of the desized, scoured and bleached fabricrised are sample.rougher Untreated than that fabric of grey shows fabrics. The indicatesindicatesmercerisedindicatesindicates that that that that fabricthe the the thesurfaces surfaces samplesurfaces surfaces of isof ofsmootherthe ofthe the thedesized, desized, desized,desized, than scoured scoured forscouredscoured the and otherand and bleached bleached treatedbleachedbleached orfabric fabric fabricfabricuntreated are theare areare maximumrough rough rough samples.roughererer erbendingthan thanthan than Comparing that that that lengththat of ofof ofgrey(warp grey greythe fabrics.and fabrics.surface fabrics. The TheplotsThe The mercerisedmercerisedobtainedmercerisedmercerised byfabric fabric fabric DIPfabric sample sample forsample sample the is is smootheris untreatedis smoother smoother smoother than andthan thanthan for treated for for for the the the other other fabrics other treated treated treated at different or or ororuntreated untreated untreateduntreated processingweft), samples. samples.samples.which samples. isstages, periodically Comparing Comparing Comparing Comparingit isreduced theobserved the the surface surfaceaf surface- that plots plotsplots plots the Fig.10: SEM micrograph of bleachedFig.10:obtainedFigureobtainedobtained obtainedsamples SEM11. bySEMby micrograph by DIPby micrographDIP DIP DIP for for for for the of the of the bleachedthe bleacheduntreated untreated untreated untreated Fig.11: samples Figure andand andand SEM treated 12. treated treated treated SEM micrograph micrograph fabrics fabrics fabrics at at of ofat at different mercerizedFig.11:different mercerizeddifferentdifferent SEM processing processing processingterprocessing micrographsample treatment stages, stages,such stages,stages, of mercerizedas desizing,itititisitisis is observed observed scouring, sampleobserved thatthatthat that thethethe the samples.bleached fabric samples have thesample. largest number of local maxima, indicatingbleaching and the mercerisation. roughest surface. It was also bleachedbleachedfoundbleachedbleached that fabric fabric infabric fabric mercerisation, samples samples samples samples ha ha ve haha vedue vevethe the thetothe largest largestthe largestlargest swelling number number numbernumber of of fibres,of oflocal local locallocal fabricmaxima, maxima, maxima,maxima, friction indicating indicating indicatingindicating will be the reduced.thethe the roughest roughestroughest roughest surf surfsurf surfaceaceace. . It . ItIt was It waswas was also alsoalso also foundfoundfoundfound that that that thatin in inmercerisation, mercerisation,in mercerisation, mercerisation, due due due due to to tothe tothe thethe swelling swelling swellingswelling of of offibres, fibres, fibres, fabric fabric fabricfabric friction friction frictionfriction will will will will be be be bereduced. reduced.reduced. reduced. Fabric surface peak height and Fabricroughness surface index peak height and roughness index Digital image processing methodsDigital were image used processingto obtain surfacemethods plotswere usedfor mercerised to obtain surface and softener plots for treated mercerised fabric and softener treated fabric samples.a) The plots thus obtained are shownb) in Fig. 12. It is observed that the scouredc) and bleached fabric sample samples. The plots thus obtained are shown in Fig. 12. It is observed that the scoured and bleached fabric sample has a higher number of peaks with a higher peak height, as shown in Fig. 12(d) and (e), also in Table 3. This has a higher number of peaks withindicates a 50higher that peakthe surfaces height, of as the shown desized, in scoured Fig.50 12(d) and bleachedand (e), fabricalso in are Table rough80 3.er Thisthan that of grey fabrics. The 40 40 indicates that the surfaces of the merceriseddesized, scoured fabric sample and bleached is smoother fabric than arefor therough otherer treatedthan that or untreatedof grey fabrics.samples.60 The Comparing the surface plots 30 30 mercerised fabric sample is smootherobtained than by for DIP the forother the treated untreated or untreatedand treated samples. fabrics atComparing different processing the surface40 stages, plots it is observed that the 20 20 obtained by DIP for the untreatedbleached and treated fabric samplesfabrics haatve different the largest processing number of stages,local maxima,it is observedindicating thethat roughest the surface. It was also Roughness Roughness 10 10 Roughness 20 bleached fabric samples have thefound largest that numberin mercerisation, of local due maxima, to the swelling indicating of fibres, the roughest fabric friction surface will. beIt reduced.was also 0 0 0 found that in mercerisation, due to the300 swelling of fibres, fabric friction will300 be reduced. 300 200 250 250 200 250 200 200 200 200 150 150 150 100 100 100 100 100 100 50 50 50 Width, mm 0 0 Length, mm Width, mm 0 0 Length, mm Width, mm 0 0 Length, mm a a bb cc a a a b b b c c c

d) e) f)

30 30 25 60 25 20 20 40 15 15 10 10 20 Roughness Roughness 5 5 Roughness 0 0 0 300 300 200 a 250 200 b 250 c 200 250 200 200 200 150 150 150 100 100 100 100 100 100 50 50 50 Width, mm 0 Length, mm Width, mm 0 0 Length, mm Width, mm 0 0 Length, mm a b c d d e e f f Figure 13. DIP d dof d pretreated cotton fabric: a) grey fabric, b) singeing, e e e c) desizing, d) scouring, e) bleaching, f f f) f mercerisation.

50 FIBRES & TEXTILES in Eastern Europe 2019, Vol. 27, 5(137)

d e f

d e f Crease recovery Table 4. Multi variant ANOVA –between pretreatment process and bending length. Note: a R Squared = 0.971 (Adjusted R Squared = 0.965), b R Squared = 0.739 (Adjusted R Squared Values of the recovery angle of untreat- = 0.687). ed and treated cotton fabrics are given in Type III sum Mean Table 2 & Figure 8 above. It is evident Source Dependent variable df F Sig. that the crease recovery angle is going of squares square bending length – warp 3.529a 4 0.882 167.093 0.000 to increase from the control to the mer- Corrected model b cerised sample. Untreated fabric shows bending length – weft 0.448 4 0.112 14.163 0.000 bending length – warp 73.103 1 73.103 13845.170 0.000 a minimum crease recovery angle, which Intercept periodically increases after desizing, bending length – weft 56.370 1 56.370 7135.451 0.000 bending length – warp 3.529 4 0.882 167.093 0.000 scouring, bleaching and mercerisation Types treatment. bending length – weft 0.448 4 0.112 14.163 0.000 bending length – warp 0.106 20 0.005 Error SEM analysis of woven cotton fabric bending length – weft 0.158 20 0.008h bending length – warp 76.737 25 SEM images at 1000 x magnification are Total given in Figures 9-12 of grey and treat- bending length – weft 56.976 25 bending length – warp 3.635 24 ed samples. As the samples were treated Corrected total with different chemicals, there are some bending length – weft 0.606 24 clear differences in the respective images. There is a clear difference in the ed and untreated fabric samples are were removed, due to which, the open respective chemical treatments for wo- shown in Figure 13. It is observed that space in the fabric increased. The rough- ven cotton fabric. Figures 9-12 show the untreated cotton fabric samples have ness of the fabric also increased, as SEM photographs of untreated, scoured, a lower average height of the peak as shown in Table 3, as compared to the bleached and mercerised cotton fabrics. compared to the desized, scoured and grey fabric. When compared to the treated fabrics bleached fabric but higher than for the (Figure 10 and 11), the surface of the mercerized fabric samples. There are In mercerisation the fibres in yarns swell, mercerised fabric sample has a smooth the least number of maxima found in thereby reducing the crimp. The compact surface, as shown in the SEM photograph the mercerisation stage, suggesting that structure of the yarns and fabric would, (Figure 11). It is a well known fact that smoothness improves with the swelling in turn, present a more uniform surface, when cotton fabric is treated with alkali of fibres in yarn, thereby reducing the thereby reducing fabric friction. under tension in order to achieve maxi- yarn crimp compact structure of yarn. mum fibre swelling, the fibre surface -be The fabric shows a uniform surface, thus ANOVA analysis comes smoother [2]. reducing the fabric friction. Experimental data were analysed using SPSS (version 20). One-way ANOVA Fabric surface peak height Surface roughness index and Multivariate Anova were used to and roughness index The roughness index values of treated compare means. The null hypothesis Digital image processing methods were and untreated samples obtained by the (Ho) is that there is no relationship be- used to obtain surface plots for merce- digital image processing method (DIP) tween the type of processing treatments rised and softener treated fabric sam- are shown in Table 3. The decrease in and the coefficient of friction (MIU), ples. The plots thus obtained are shown the surface roughness or increase in the bending length and crease recovery of in Figure 13. It is observed that the smoothness of the fabrics due to merce- fabrics. In the alternative hypothesis, scoured and bleached fabric sample has risation treatment is 42 %, which is very there is a relationship between the type a higher number of peaks with a higher encouraging. It is concluded that in mer- of processing treatments and the coeffi- peak height, as shown in Figures 13.d cerisation swelling in fibres is obtained cient of friction (MIU), bending length and 13.e, also in Table 3. This indicates due to this process reducing the surface and crease recovery of fabrics. Ho will be that the surfaces of the desized, scoured irregularities of fabrics and, consequent- rejected when the p-value turns out to be and bleached fabric are rougher than that ly, SMD values. From the bleached to less than a pre-determined significance of grey fabrics. The mercerised fabric mercerized fabric, the surface Roughness level, i.e. 0.05. sample is smoother than for the other Index is 73%, from scouring to merceri- treated or untreated samples. Comparing sation – 68%, from desizing to merceri- As per the results shown in Table 4 for the surface plots obtained by DIP for the sation – 46%, and from grey to merceri- multi-variant ANOVA analysis between untreated and treated fabrics at different sation it is 42%. types of processing treatment and the processing stages, it is observed that the bending length, the null hypothesis (Ho) bleached fabric samples have the largest In the grey stage the starch applied is rejected as the p-value turns out to be number of local maxima, indicating the during sizing makes the fabric surface less than the pre-determined significance roughest surface. It was also found that smooth and stiff. It in shown in Table 2 level, i.e. 0.05. It indicates that there is in mercerisation, due to the swelling of and Figure 6 that the coefficient of fric- a relationship between the processing fibres, fabric friction will be reduced. tion is less compared to the scoured or treatment and bending length. bleached fabric and that the peak height Surface roughness of fabrics is also lower than for scoured or bleached The regression coefficient (R Squared) fabric sample 7. values are 0.97 & 0.68, respectively, indi- Surface plots cating a very strong relationship between The surface plots obtained by digital During the desizing and bleaching stage, the processing treatment and bending image processing methods for pretreat- the starch, wax and other foreign matter length (warp & weft).

FIBRES & TEXTILES in Eastern Europe 2019, Vol. 27, 5(137) 51 Table 5. One way ANOVA –between pretreatment process and crease recovery. the fabrics to recover from deformation. The materials which have good crease Sum of squares df Mean square F Sig. recovery properties exhibit excellent soft Between groups 7130.240 4 1782.560 810.255 0.000 handle. It is seen that the crease recovery Within groups 44.000 20 2.200 angle increases from desized to merce- Total 7174.240 24 rised fabric samples.

Table 6. One way ANOVA – between pretreatment process and peak height in DIP method. The Kawabata evaluation study shows a Note: R Squared = 0.992 (Adjusted R Squared = 0.991). that the value of the coefficient of fric-

Type III sum tion (MIU) is higher for bleached fabric Source df Mean square F Sig. of squares in both the warp and weft directions than Corrected model 6344.000a 4 1586.000 634.400 0.000 for grey or mercerised fabric samples. Intercept 33856.000 1 33856.000 13542.400 0.000 Types 6344.000 4 1586.000 634.400 0.000 From the digital image processing meth- Error 50.000 20 2.500 od, the surface roughness value of the Total 40250.000 25 mercerised fabric samples are lower than Corrected total 6394.000 24 for the bleached or scoured fabric samples. This indicates that the bleached and Table 7. One way ANOVA –between pretreatment process and coefficient of friction. scoured fabrics are rougher than the mercerised fabric samples. The maximum de- Type III sum Mean Source Dependent variable df F Sig. crease in roughness was found when the of squares square fabric was treated in the mercerised stage. coefficient of friction-warp 0.001a 4 0.000 5.048 0.006 Corrected model coefficient of friction-weft 0.003b 4 0.001 320.600 0.000 coefficient of friction-warp 0.601 1 0.601 11550.481 0.000 Intercept coefficient of friction-weft 0.590 1 0.590 235929.600 0.000 References coefficient of friction-warp 0.001 4 0.000 5.048 0.006 Types of fabric 1. Mao N et al. Characteristics Of Fabric coefficient of friction-weft 0.003 4 0.001 320.600 0.000 -To-Fabric Self-Friction Properties. In: The 90th Textile Institute World Confe- coefficient of friction-warp 0.001 20 5.200E-005 Error rence, 25-28 Apr 2016, Poznan, Poland. coefficient of friction-weft 5.000E-005 20 2.500E-006 2. Moses JJ1, Venkataraman. Study of Mechanical and Surface Properties on coefficient of friction-warp 0.603 25 Total some Chemical Treated Cotton Fabric coefficient of friction-weft 0.593 25 by KES-F, SEM and FTIR Analysis, De- coefficient of friction-warp 0.002 24 Corrected total partment of Applied Science, PSG Col- coefficient of friction-weft 0.003 24 lege of Technology, Coimbatore, India. 3. Czaplicki Z, Matyjas-Zgondek E, Ser- weta W. Directions of the Finishing To understand any relation between dif- Conclusions of Fibres and Textile Development. ferent concentrations of softeners and the FIBRES & TEXTILES in Eastern Eu- bending length and crease recovery, one It is observed that the mercerised treat- rope 2018; 26, 6(132): 133-141. DOI: way ANOVA was applied, the results of ed cotton fabrics show a lower bending 10.5604/01.3001.0012.5167. which are shown in Table 5. From the length value in comparison to bleached 4. Trotman E R. Dyeing and Chemical table it is clear that the null hypothesis or scoured fabric, indicating that the pre- Technology of Textile Fibres, Fourth Edition, January 1970. (Ho) is rejected as the p-value turns out treatment process affects the feel of fabric. It is also observed that in grey or mer- 5. Behera B K, Pattanayak A K. Indian J to be less than the pre-determined signif- Fibre Text Res, (33) (2008) 230. icance level i.e. 0.05. This shows there cerised fabric samples, there is a reduc- 6. Kawabata S. The Standardization and is a relationship between the processing tion in the bending length. The reduction Analysis of Hand Evaluation, Japan, treatment and crease recovery. in the bending length indicates reduced Osaka: Hand Eval. Standardization rigidity/stiffness and, hence, improved Committee, Textile Mach. Soc. Jpn., The regression coefficient (R) value is softness of the fabric. Therefore, there is 1980. 86, indicating a very strong relationship a reduction in the bending length of the 7. Study of the Characteristics of Polymer fabric due to the swelling of fibres, there- Deposition By Electrospraying, Amit between the concentration of softeners Arunchandra Jadhav, School of Fashion and coefficient of friction (MIU). by decreasing the friction as the samples and Textiles Design and Social Context have become softer. Portfolio RMIT University January 2014, From Tables 6 and 7, it is shown that Doctor of Philosophy. the null hypothesis (Ho) is rejected as Scoured or bleached fabric show a min- 8. Nawaza N, Troynikovb O, Watson C. the p-value turns out to be less than the imum crease recovery angle, which is Evaluation of Surface Characteristics of pre-determined significance level i.e. periodically increased after the merce- Fabrics Suitable for Skin Layer of Fire- fighters’ Protective Clothing. Internatio- 0.05. This shows that there is a relation- rised treatment. It is clear that the crease nal conference on Physics Science and ship between the processing treatment recovery of mercerised samples is higher Technology 2011, Physics Procedia 22 and peak height in the DIP method and than for the scoured or bleached fabric (2011) 478-486. the coefficient of friction, respectively. sample. This may be due to the swell- The regression coefficient (R) values are ing of fibre in the fabric. It appears that 0.99 & 0.98, respectively. the treatment developed the ability of Received 27.02.2019 Reviewed 07.05.2019

52 FIBRES & TEXTILES in Eastern Europe 2019, Vol. 27, 5(137)