Prediction of Certain Low Stress Mechanical Properties of Knitted Fabrics from Their Structural Parameters

Transcription

1 Prediction of ertain Low Stress Mechanical Properties of Knitted Fabrics from Their Structural Parameters R. Varadaraju, Srinivasan J., PhD Kumaraguru ollege of Technology, Fashion Technology, oimbatore, Tamil Nadu INDIA orrespondence to: R. Varadaraju ABSTRAT Knitted fabrics are preferred as clothing materials because of of their outstanding comfort quality. 16 plain knitted fabric samples were produced from 4 combed ring spun yarn of linear densities 29.5 Tex, 23.6, Tex 19.7 Tex and 17.4 Tex and 4 different stitch lengths from each yarn linear density were selected for this study. The fabric samples were relaxed and then tested for tensile shear and bending properties using Kawabata tester s. KES- FB1and KES- FB2.The effect of various fabric structural parameters on fabric low stress mechanical properties was studied. The fabric shear rigidity, bending rigidity, shear hysteresis, bending hysteresis, and tensile linearity were positively correlated with the fabric GSM, thickness, and tightness factor and negatively correlated with fabric linear Stitch modulus, areal stitch modulus, volume stitch modulus, and porosity. The fabric tensile elongation was positively correlated with the fabric linear stitch modulus, areal stitch modulus, volume Stitch modulus, and porosity and negatively correlated with the fabric GSM, thickness, and fabric tightness factor. The above properties were higher in course direction than in wale direction. Separate prediction equations were developed for fabric low stress mechanical properties from Tightness factor, Volume Stitch modulus, and Porosity Keywords: Bending rigidity, Shear rigidity Tensile energy, Tensile Linearity, Tensile Resilience, Tensile extension, Bending hysteresis, Shear hysteresis, Tightness factor, loop length, linear Stitch modulus, areal Stitch modulus Volume Stitch modulus, Porosity, GSM, Tightness factor and Thickness INTRODUTION The functional properties of knitted fabrics are related to low stress mechanical properties, such as bending, shear, and tensile. An increase in bending and shear parameters such as bending and shear rigidity, hysteresis of bending, and shear, result in a decrease in the drape structure of the fabric, something undesirable in most cases [1]). In most cases, lower bending and shear parameters and lower roughness for knitted fabrics are necessary for best handle [2]. Many examples exist showing the relationship between fabric functional properties and bending and shear properties. The bending characteristics of plain knit fabrics were analyzed assuming that each wale in the fabric behaved as a pair of double helices [3]. The bending and shear properties of woven and knitted fabrics were compared [4]. A straight parallel yarns model was constructed in which the knitted structure is assumed to consist of a series of straight yarns to explain the bending behavior of several basic knit fabrics [5]. To date, most studies have shown that fabric bending and shear rigidity parameters increase with increases in relaxation, [3] [4] [6] [7]. Scouring and bleaching treatments decreases RT, T and increases LT Shear rigidity, Shear hysteresis, and areal density [8] stitch length is the dominating factor affecting the courses percm and wale per cm, whereas yarn linear density and twist multiplier has only marginal effect [9]. There is a general trend that an increase in the tightness factor leads to an increase in bending and shear parameters (B, 2HB, G, 2HG) [10] [11]. Bending and shear parameters in the course direction are greater than those in the wale direction [1]. The structural parameters of knitted fabrics namely GSM, Thickness Linear Stitch modulus, Surface Stitch modulus, Volume Stitch modulus, Porosity and tightness factor were used to study the thermal properties of knitted fabrics [12]. The main objective of this study was to develop prediction equations for the low stress bending shear and tensile properties of knitted fabrics from their structural parameters. MATERIALS AND METHODS Nomenclature and units of measurements B = stitch height (mm) l = stitch length (thread consumption of a stitch) (mm) Yt = Yarn linear density, 1 g per 1000 m (Tex) Journal of Engineered Fibers and Fabrics 11

2 T.F = Tightness factor, (tex1/2 mm/stitch length in cms); Dt = Theoretical minimum Yarn diameter (mm) = square root of (4Yt/ 3.14* fiber density) Dy = Actual Yarn diameter (mm) GSM = mass per unit area (grams per square meter) R = correlation coefficient T = thickness (mm) = stitch width (mm) Pf= fiber density (kg/meter3) Py = Yarn density (kg/meter3) Pkf = knitted fabric density (kg/meter3) Knitted Fabric Structural Parameters LSM SSM VSM linear stitch x modulus 1 surface stitch x modulus 2 volume stitch x modulus 3 Porosity Unit less x 4 GSM Gms per square meter Areal density x 5 T (mm) mm T.F ourse Direction Properties BR- 2HB- G- 2HG- LT- bending rigidity bending hysteresis shear hysteresis tensile linearity T- Gf*cm/cm tensile energy Y 6 RT- EMT- Unit less Unit less Unit less (Tex)1/2/ cms Gmf*cm2/cm Gfcm/cm 10-2 *Gf* cm/deg 10-2 *Gf*cm Unit less Unit less % ale Direction Properties Fabric Thickness Tightness factor tensile resilience tensile elongation BR- Gmf*cm2/cm bending rigidity Y 9 2HB- Gfcm/cm bending hysteresis Y 10 1/100*Gf* G- shear rigidity Y 11 cm/deg 2HG- 1/100*Gf*cm Shear hysteresis Y 12 LT- Unit less tensile linearity Y 13 T- Gf*cm/cm tensile energy Y 14 RT- Unit less tensile resilience Y 15 EMT- % tensile elongation Y 16 Superscripts and subscripts - ourse direction - ale direction f fiber kf knitted fabric y yarn x 6 x 7 Y 1 Y 2 shear rigidity Y 3 Y 4 Y 5 Y 7 Y 8 MATERIALS 16 plain knitted fabric samples were produced from 4 combed yarn linear densities (29.5, 23.6, 19.7, 17.4 Tex) and 4 different stitch lengths from each yarn linear densities were selected for this study. The fabric samples were relaxed and Tensile, shear and bending tests were carried out using Kawabata KES- FB1, KES- FB2 testers. Defining Knitted Fabric Structural Parameters The definitions of structural parameters of knitted fabrics used in this study are given below. X1- Linear Stitch modulus, is the ratio of the stitch length to the minimum yarn diameter X2- Surface Stitch modulus, is the ratio of the stitch area to the area occupied by the yarn used for making the stitch X3- Volume Stitch modulus is the ratio of the stitch volume to the volume of the yarn used for making the stitch X4 Porosity is a measure for the volume portion of holes in the knitted fabric X5-(GSM) Grams per square meter area of the fabric X6-fabric thickness in mm X7-Tightness factor is calculated as the ratio of the square root of yarn Tex to the loop length. Tightness factor is a measure of the tightness of the fabric. As the tightness increases (or as the slackness decreases), the tightness factor increases. Determination of Knitted Fabric Structural Parameters Stitch Length (l) It is the length of yarn in mm for one loop. The loop value is measured by taking 50 ales. 50 ales are marked on the fabric surface and then the yarn for that particular place is unraveled, straightened and measured in mm. by substituting the measured values in the formula, the loop length is measured. Loop Length (mm) = Length of yarn / Number of loops (50) ales and ourses per Inch Fabric samples were taken and laid flat on a table. reases and wrinkles were removed without distorting. On one side of the test specimen, with the help of pick glass or magnifying glass, the ales per Inch and courses per Inch were counted. Five such readings were taken and the average was accounted. [ASTM D 3887: 1996.] Journal of Engineered Fibers and Fabrics 12

3 X6- Thickness (T) Perpendicular distance between two reference plates exerting a load of 20 gm / cm 2. Thickness was measured using a thickness meter. Thickness for the fabric was measured at five different places and the average value was noted. [ASTM D 1777:1996, IS: 7702:1975]. X5 Mass per unit area (GSM) in Gms per square meter was determined by using a cutting device (round, area 100 cm 2 ); the fabric was cut and weighted in a weighting balance. Grams per Square Meter (GSM) of the fabric was measured at five different places and the average value was noted. [ASTM D 3776: 1996.] Among the secondary parameters, the following were determined: X4 porosity is calculated as following = 1- (Pkf/Py) X7 Tightness factor (T.F), is calculated as the ratio of the square root of yarn Tex to the loop length. X1-Linear stitch modulus (LSM) = Stitch length (l)/ Dt X2-Surface stitch modulus (SSM) = (B/l)* Sq root of (3.14*Py/4Yt) X3-Volume stitch modulus (VSM) = ((4**B *Tkf)/ (3.14*Dy*Dy*l)) Relaxation Treatments All fabrics were relaxed by dry relaxation. For dry relaxation, fabrics were placed on a flat surface in a standard atmosphere (20 at 65% RH) for 24 Hours. Before measurements were taken, the fabrics were conditioned for 24 h in a standard atmosphere [ASTM: D (reapproved 1996]. Testing of Low Stress Mechanical Properties of Knitted Fabrics The shear properties of the fabrics were measured by a Kawabata, KES-FB system, using KES- FB1 tester with a sample size of 20cms width 5cms length, shear weight of 10gf/cm and shear angle of -8 to+8 degrees, The Tensile and shear properties of the fabrics were measured by a Kawabata, KES-FB system, using KES-FB1 tester with a sample size of 20cms width 2.5cms length. And a maximum load of 250gf/cm the bending properties of the fabrics were measured by KES- FB2 tester with a sample size of 20cms x5cms. Bending moment and shear force were applied about axis parallel to the course and wale directions, respectively Each test was repeated five times for each direction, and for each of the 16 fabric samples Bending rigidity (B), hysteresis of bending (2HB), shear Rigidity (G) and hysteresis of shear (2HG) were obtained from the KES-FB test system RESULTS AND DISUSSION The knitted Fabric Properties in ourse and ale Direction, linear orrelation Matrix, and R 2 matrix of quadratic regressions of Structural Parameters and fabric Properties are given in Table I, Table II and Table IV respectively. Bending Rigidity (BR) The fabric Bending rigidity (BR) is the resistance to bending. A higher Bending rigidity (BR) indicates its higher resistance to bending. The increase in fabric tightness factor, GSM, and decrease in porosity gives an increase in bending rigidity. The increase in fabric Tightness factor increases the inter yarn contact and frictional force. The increase in fabric GSM increases the number of fibers in the fabric cross section. The decrease in fabric porosity increases the inter yarn and inter fiber friction. The increase in bending rigidity (BR) is due to the increase in the number of fibers in the fabric cross-section, increase in the interyarn and inter fiber frictional forces. The Bending rigidity (BR) is higher in course direction than in wale direction. This is due to the presence of more number of yarn cross-sections in course direction than in wale direction.the decrease in LSM, SSM and VSM reduces air gaps in the structure which increases the interyarn and inter fiber friction. This contributes for the increase in bending rigidity (BR) Bending Hysteresis (2HB) The fabric Bending hysteresis (2HB) indicates the ability of the fabric to recover after it is being bent. The lower the fabric bending hysteresis (2HB), the higher is its ability to recover after being bent. The increase in fabric tightness factor, GSM, and decrease in porosity gives an increase in bending hysteresis (2HB). The increase in fabric Tightness factor increases the inter yarn contact and frictional forces. The increase in fabric GSM increases the number of fibers in the fabric cross section. The decrease in fabric porosity increases the inter yarn and inter fiber friction. The increase in Bending hysteresis (2HB) is Journal of Engineered Fibers and Fabrics 13

4 due to the increase in the number of fibers in the fabric cross-section, increase in the inter yarn and inter fiber frictional forces.the Bending hysteresis (2HB) is higher in course direction than in wale direction. This is due to the presence of more number of yarn cross-sections in course direction than in wale direction.the decrease in LSM, SSM and VSM reduces air gaps in the structure which increases the interyarn and inter fiber friction. This contributes for the increase in bending hysteresis (2HB) Shear Rigidity (G) Shear properties are affected by the slipperiness at loop intersections, the coefficient of friction, the contact length of the loops and the stitch density.the increase in fabric tightness factor, GSM, and decrease in porosity increases the fabric shear rigidity (G). The increase in Tightness factor increases the inter yarn contact and frictional force. The increase in GSM increases the number of fibers in the fabric cross section. The decrease in fabric porosity increases the inter yarn and inter fiber friction. The increase in shear rigidity (G) is due to the increase in the number of fibers in the fabric cross-section, increase in the interyarn and inter fiber frictional forces. The shear rigidity (G) is higher in course direction than in wale direction. This is due to the presence of more number of yarn cross-sections in course direction than in wale direction.the decrease in LSM, SSM and VSM reduces air gaps in the structure which increases the interyarn and inter fiber friction. This contributes for the increase in shear rigidity (G) Shear Hysteresis (2HG) The fabric hysteresis (2HG) indicates the ability of the fabric to recover after it is being sheared. The lower the fabric hysteresis (2HG) of the fabric, the higher is its ability to recover after it is being sheared The increase in fabric tightness factor, GSM, and decrease in porosity gives an increase in fabric shear hysteresis (2HG) The increase in fabric Tightness factor increases the inter yarn contact and frictional force. The increase in fabric GSM increases the number of fibers in the fabric cross section. The decrease in fabric porosity increases the inter yarn and inter fiber friction. The increase in shear hysteresis (2HG is due to the increase in the number of fibers in the fabric cross-section, increase in the inter yarn and inter fiber frictional forces. The shear hysteresis (2HG) is higher in course direction than in wale direction. This is due to the presence of more number of yarn cross-sections in course direction than in wale direction.the decrease in LSM, SSM and VSM reduces air gaps in the structure which increases the inter yarn and inter fiber friction. This contributes for the increase in shear hysteresis (2HG) Tensile Linearity (LT) The tensile linearity (LT) value of 1 means the fabric is perfectly elastic like a spring, and the load elongation curve is linear. The increase in fabric tightness factor, GSM, and decrease in porosity gives an increase in tensile linearity(lt) The increase in fabric Tightness factor increases the inter yarn contact and frictional force. The increase in fabric GSM increases the number of fibers in the fabric cross section. The decrease in fabric porosity increases the inter yarn and inter fiber friction. The increase in tensile linearity (LT) is due to the increase in the number of fibers in the fabric cross-section, increase in the inter yarn and inter fiber frictional forces. The tensile linearity (LT) is higher in course direction than in wale direction. This is due to the presence of more number of yarn cross-sections in course direction than in wale direction.the decrease in LSM, SSM and VSM reduces air gaps in the structure which increases the inter yarn and inter fiber friction. This contributes for the increase in tensile linearity (LT) Tensile Energy (T) Tensile energy is the work done during extension of the fabric. There was no strong correlation found between tensile energy (T) and fabric structural parameters Tensile Resilience (RT) Tensile resilience (RT) indicates the ability of the fabric to recover the work done after it is being elongated. Higher Tensile resilience (RT) of the fabric means higher ability to recover the work done after being elongated. The maximum value being 1 means the work done during elongation is completely recovered. The increase in fabric tightness factor, GSM, and decrease in porosity gives an increase in tensile resilience (RT). The increase in fabric Tightness factor increases the inter yarn contact and frictional force. The increase in fabric GSM increases the number of fibers in the fabric cross section. The decrease in fabric porosity increases the inter yarn and inter fiber friction. The increase in tensile resilience (RT) is due to the increase in the number of fibers in the fabric cross-section, increase in the inter yarn and inter fiber frictional forces. The tensile resilience (RT) is higher in course direction than in wale direction. This is due to the presence of more yarn cross-sections in course direction than in wale direction. The decrease in LSM, SSM and VSM reduces air gaps in the structure which increase the interyarn and inter fiber friction. This contributes for the increase in tensile resilience (RT). There is a Journal of Engineered Fibers and Fabrics 14

5 strong correlation between Tensile Resilience and fabric structural parameters in course direction only. Tensile Elongation (ET) The fabric tensile elongation (ET) increase can be attributed to the easiness of slippage of yarn and increase in stitch length. The increase in fabric tightness factor, GSM, and decrease in porosity gives a decrease in fabric tensile elongation (ET) The increase in fabric Tightness factor increases the inter yarn contact and frictional force. The increase in fabric GSM increases the number of fibers in the fabric cross section. The decrease in fabric porosity increases the inter yarn and inter fiber friction. The decrease in tensile elongation (ET) is due to the increase in the number of fibers in the fabric crosssection, increase in the inter yarn and inter fiber frictional forces. The tensile elongation (ET) is higher in course direction than in wale direction. This is due to the presence of yarn in course direction for easy slippage than in wale direction. The decrease in LSM, SSM and VSM reduces air gaps in the structure which increases the inter yarn and inter fiber friction. This contributes for the decrease in Tensile Elongation. Prediction of Mechanical Properties from Structural Parameters (Tables V to X) The effect of Tightness factor, Volume stitch modulus and Porosity on the fabric low stress mechanical properties was studied separately and the prediction equations were developed in course and wale directions in the form Y=b 1 X + b 2 X 2 +c here Y is the fabric low stress mechanical property X is the fabric parameter, b 1 and b 2 are the corresponding regression coefficient and c is a constant. It was found that fabric Shear rigidity, Bending rigidity, Shear hysteresis, Bending hysteresis and tensile linearity are positively correlated with tightness factor and are negatively correlated with Volume Stitch modulus and Porosity. The fabric tensile elongation is positively correlated with the Volume Stitch modulus and Porosity and negatively correlated with tightness factor.there is no correlation between Tensile Energy and fabric structural parameters. There is a correlation between Tensile Resilience and fabric structural parameters in course direction only. omparison of Observed and Predicted Properties The effect of Tightness factor, on the fabric low stress mechanical properties in course direction is given in the Figures 1 to 8 for both the observed and predicted from the quadratic equations. e found that there is a significant closeness between the actual and predicted values for all properties except tensile energy. So we can use the equations for predicting the low stress mechanical properties of plain knitted fabrics. orrelation between Fabric Properties (Table III) There is a strong correlation between different low stress mechanical properties. The increase in fabric Tightness factor increases the inter yarn contact and frictional forces. The increase in fabric GSM increases the number of fibers in the fabric cross section. The decrease in fabric porosity increases the inter yarn and inter fiber friction. The decrease in LSM, SSM and VSM reduces air gaps in the structure which increases the inter yarn and inter fiber friction. All low stress mechanical properties depend upon the interyarn and inter fiber frictional forces. This is the reason for the strong correlation between different low stress mechanical properties as shown in the Table II. Journal of Engineered Fibers and Fabrics 15

6 TABLE I. Knitted fabric properties in course direction and in wale direction. OURSE DIRETION Sample STRUTURAL PARAMETERS BENDING SHEAR TENSILE PROPERTIES number x1 x2 x3 x4 x5 x6 x7 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 T- MM T.F BR- LSM SSM VSM POROS- GSM T ET ALE DIRETION Sample STRUTURAL PARAMETERS BENDING SHEAR TENSILE PROPERTIES number x1 x2 x3 x4 x5 x6 x7 y9 y10 y11 y12 y13 y14 y15 y16 T- MM T.F B- LSM SSM VSM POROS- GSM HB- 2HB- G- G- 2HG- 2HG- LT- LT- T- RT- RT- ET- Journal of Engineered Fibers and Fabrics 16

7 ALE DIRETION TABLE II. Linear correlation matrix - structural parameters and fabric properties. BR- 2HB- G- 2HG- LT- T- RT- EMT- LSM SSM VSM Porosity GSM T (mm) T.F BR HB G HG LT T RT EMT OURSE DIRETION BR- 2HB- G- 2HG- LT- T- RT- EMT- LSM SSM VSM porosity GSM T (mm) T.F BR HB G HG LT T RT EMT TABLE III. Linear correlation matrix of structural parameters. LSM SSM VSM porosity GSM T (mm) T.F LSM SSM VSM porosity GSM T (mm) T.F Journal of Engineered Fibers and Fabrics 17

8 TABLE IV. R 2 matrix of quadratic regression of low stress mechanical properties (y) on structural parameters. TABLE VII. Regressoion coefficents of low stress mechanical properties (Y) on porosity(x) in course direction Y b 1 b 2 R 2 Y Y Y Y Y Y Y Y TABLE VIII. Regressoion coefficents of low stress mechanical properties (Y) on tightness factor (X) in wale direction. Y b 1 b 2 c R 2 Y Y Y Y Y Y Y Y TABLE V. Regressoion coefficents of low stress mechanical properties (Y) on tightness factor (X) in course direction. Y b 1 b 2 c R 2 Y Y Y Y Y Y Y Y TABLE VI. Regressoion coefficents of low stress mechanical properties (Y) on vsm (X) in course direction. Y b 1 b 2 R 2 Y Y Y Y Y Y Y Y TABLE IX. Regressoion coefficents of low stress mechanical properties (y) on vsm (x) in wale direction. Y b 1 b 2 R 2 Y Y Y Y Y Y Y Y TABLE X. Regressoion coefficents of low stress mechanical properties (Y) on porosity(x) in wale direction. Y b 1 b 2 R 2 Y Y Y Y Y Y Y Y Journal of Engineered Fibers and Fabrics 18

9 FIGURE 1. Effect of Tightness Factor (VAROO7 -unit less) on Bending Rigidity (B) in course direction. FIGURE 4. Effect of Tightness Factor (VAROO7 -unit less) on Shear hysteresis (2HG) in course Direction. FIGURE 5. Effect of Tightness Factor (VAROO7 -unit less) on Tensile Linearity (LT) in course Direction. FIGURE 2. Effect of Tightness Factor (VAROO7 -unit less) on Bending Hysteresis (2HB) in course direction. FIGURE 6. Effect of Tightness Factor (VAROO7-unit less) on Tensile Energy (T) in course Direction. FIGURE 3. Effect of Tightness Factor (VAROO7 -unit less) on Shear Rigidity (G) in course Direction. FIGURE 7. Effect of Tightness Factor (VAROO7-unitless) on Tensile Resilience (RT) in course Direction. Journal of Engineered Fibers and Fabrics 19

10 FIGURE 8. Effect of Tightness Factor (VAROO7-unitless) on Tensile Elongation (ET) in course Direction. ONLUSION 1. It was found that fabric Shear rigidity, Bending rigidity, Shear hysteresis, Bending hysteresis and Tensile linearity are positively correlated with GSM, thickness and tightness factor and are negatively correlated with Linear Stitch modulus, Surface Stitch modulus Volume Stitch modulus and Porosity. 2. The fabric Tensile elongation is positively correlated with the Linear Stitch modulus, Surface Stitch modulus, Volume Stitch modulus and Porosity and negatively correlated with GSM, thickness and tightness factor. 3. The fabric low stress mechanical properties are higher in course direction than in wale direction. 4. There is no correlation between Tensile Energy and fabric structural parameters. 5. There is a correlation between Tensile Resilience and fabric structural parameters in course direction only. 6. The prediction equations were developed for the fabric low stress mechanical properties from its Tightness Factor, porosity, and Volume Stitch modulus separately and it was observed that there is a strong correlation between the actual and predicted. REFERENES [1] Gaucher, M.L. and King, M.., Predicting the Drape oefficient of Knitted Fabrics, Textile Research Journal, 53, 1983, [2] hen, P.L., Barker, R.L., Smith, G.. and Scruggs, B., Handle of eft Knit Fabrics, Textile Research Journal, 83, , [3] Hamilton, R.J. and Postle, R., the Bending and Recovery Properties of ool Plain Knitted Fabrics, Textile Research Journal, 44, [4] Gibson, V.L. and Postle, R., An Analysis of the Bending and Shear Properties of oven, Double Knitted and arp Knitted Outerwear Fabrics, Textile Research Journal. 48, [5] Alimaa, D., Matsuo, T., Nakajima, M. and Takahashi,M., Effects of Yarn Bending and Fabric Structure on the Bending Properties of Plain and Rib Knitted Fabrics, Textile Research Journal, 70, [6] Hamilton, R.J. and Postle, R., Shear Properties of ool Plain Knitted Fabrics, Textile Research Journal, 46, , [7] Stewart, B.F. and Postle, R., the Effect of Felting on the Bending and Shear Properties of Knitted ool Fabrics, Textile Research Journal, 44, [8] H.Hassani, effect of different processing stages on mechanical and surface properties of cotton knitted fabrics, IJFTR V35, June 2010 pp [9] G.Singh, K.Roy R.Varshney& A.Goyal. Dimensional parameters of single jercy cotton knitted fabrics IJFTR V36, June 2011 pp [10] E. Finnimore., objective measurement, application to product design and process control edited by Kawabata et.al TMSJ, [11] Mehmet (UAR) Mechanical Behavior of Knitted Fabrics under Bending and Shear Deformation Turkish J. Eng. environment Sci.27 (2003), [12] Salopek ubric, Z. Skenderi, A. Mihelic- Bogdanic. M. Andrassy., 2012 Experimental study of thermal resistance of knitted fabrics. Experimental Thermal and Fluid Science V. 38, 2012, pp AUTHORS ADDRESSES R. Varadaraju Srinivasan J., PhD Kumaraguru ollege of Technology Fashion Technology hinnavedampatti P.O. hinthamani Nagar oimbatore, Tamil Nadu INDIA Journal of Engineered Fibers and Fabrics 20