Variation of GSM in Different Processing Stages of Dyeing & Finishing

Study on Variation of GSM in Different Processing Stages of Dyeing & Finishing

M. Fazlul Haque & Abu Salah
Department of Textile Engineering
Dhaka University of Engineering & Technology (DUET)
Gazipur -1700, Bangladesh

 

ABSTRACT
Manufacturing of knitted fabrics involves intermeshing of yarn loops where one loop is drawn through another to form a stitch. Since the last few years knitted fabrics are used in manufacturing of fashion garments and even it has the potential in the formal wear segments. Accordingly, many developments have taken place in the machinery for processing of knitted fabrics in both tubular process and open width forms. Specifications of knitted fabric usually include loop density, width of the fabric, weight per square meter and the loop length. A manufacturer of knit fabrics have to consider to produce a fabric the following parameter of yarn & knitting machine such as Machine dia, m/c Gauge, Yarn Count, Stitch Length, GSM etc. Our project basically is on variation of GSM in various stages of processing specifically in dyeing & finishing and machines which are related to knit fabric processing.

Keywords: GSM, knitted fabric, dyeing, fabric processing, finishing.

1. INTRODUCTION

1.1 Introduction
A manufacturer or user of cotton knit fabrics accumulates large amount of data as related to dimensions of the fabrics. This presentation will show that knit fabric GSM variation can be measured and understood from empirical data gathered from those fabrics. Fabric is a manufactured assembly of fibers and yarns that has substantial surface area in relation to its thickness and sufficient cohesion to give the assembly useful mechanical strength.

1.2 Objectives
The overall objective of this study was to assess the variation of fabric GSM in different stages of knit fabrics processing.

Specific objectives of this study were:

  • To assess the variation of knit fabric GSM on different knitting structure.
  • To assess the variation of fabric GSM in different processing stages on same knitting structure.
  • To compare the values of GSM in different stages of processing.

2. LITERATURE REVIEW

2.1 INTRODUCTION
GSM exists at the various stages of wet processing in terms of process machinery and methods followed by calendaring or compacting which is often, the final operation prior to the packaging step. The level of GSM control needed, composition of yarn (100% cotton, blends) and type of chemicals applied to the fabric decide the final process, i.e., whether calendaring or compacting. Variable compactors are used to achieve specific stitch count and wet compacting is also carried out in certain cases. Yarns of different counts knitted to the same loop length display different physical properties such as drape, openness, permeability, spirality and handle etc. GSM can be controlled either by taking a coarse count of yarn or for the same count of yarn increasing the stitches per inch. Stitch per inches can be increased by either resorting to a higher gauge machine or by decreasing the loop length.

In modern weft knitting machine there is a positive feeder called IRO which regulates the speed of the fed yarn. If the speed of IRO increases, the quantity of yarn passing in the m/c increases, so the loop size increases and hence the GSM decreases. If the speed decreases the reverse happens and the GSM increases. The loop size can also be decreased by adjusting the distance between the cylinder and the dial needles: If the distance is more the loop size increases and hence the GSM decreases

2.2 DEFINITION
Knitting is a process of fabric forming by the intermeshing of loops of yarn. When one loop is drawn through another, loop stitch is formed. Weft knitting is a method of forming a fabric in which the loops are made in horizontal way from a single yarn and intermeshing of loops take place in a circular or flat form or across wise basis.

Weight per unit area of fabric i.e. GSM is an important property that is again related to a host of other properties. The weight is determined by two factors that interact: the loop size and the yarn size. The effect of the loop size is simple to express: if the size of the yarn remains constant, then increase of loop size produces a decrease of weight per unit area. The effect is an inverse ratio.

Stitch density is the most important one in defining knitted fabric properties and is directly related to appearance, weight per unit area, thickness, drape and many other factors.

The stitch length is the absolute quantity of any knitted fabric, as the loop size increase the loop density deceases. For simple fabrics the relationship can be expressed in a single equation:

……….k
K = ———
……….I2

Where S is the stitch density, I is the loop length and K is a constant for the particular construction. A large amount of data and research work has been carried out relating the above expression to the characteristics of plain fabric, and definite values of K have been proposed. For other constructions, while the proposition still holds the situation is more complex and further study is required.

2.3 IMPORTANCE OF KNITTED FABRICS
It is a well-known fact that knitted fabrics are being increasingly used for manufacturing garments as the knitted goods offer several advantages.

Advantages from the user side:

  • Quick response to market requirement means (very fashionable).
  • High elasticity (controllable through the construction).
  • Easy care.
  • Good body fitting.
  • High volume and soft handle.
  • Cooling or warming depending on construction.

Advantages from the producing side:

  • Higher productivity (three times higher than weaving looms).
  • Manufacturing costs for knitted goods are approximately 50% lower than for woven fabric.
  • Lower investments necessary (so called “home shops”).
  • Suitable for all types of fibers.
  • No necessary for Sizing.

2.4 GSM OF KNITTED FABRICS
Wet processing of knitted fabrics, often, causes distortions in the fabrics like creases and wrinkles. In knitted fabrics, all types of shrinkage takes place when the moisture content is below 50%. The loop length is the only main factor influencing the dimensional properties of the knitted fabrics. Loop length and yarn diameter significantly affects the GSM of the fabric. Yarns of different counts knitted to the same loop length display different physical properties such as shrinkage, drape, openness, permeability, handle, etc. Compaction is carried out as a measure of increasing the dimensional stability and much attention have been given in the assessment of GSM. Positive feeders are often employed to ensure much closer tolerances between feeders in respect of course length. The GSM of the fabrics is determined by two factors that interact in the knitted fabrics, i.e., the loop size and the yarn size. The cover factor, i.e., fractional area or space occupied by the knitted loop is given by the ratio of area covered by yarn in one loop and area of one loop.

2.5 DYEING PROCESS

Pretreatment curve for light shade
Fig 2.1 Pretreatment curve for light shade
Dyeing curve
Fig 2.2 Dyeing curve

2.6 FINISHING PROCESS

2.6.1 OVERVIEW OF STENTER MACHINE

2.6.1 (a) Fabric Feeding
The In-feed system can be supplied suitable to take up fabrics either from batches or loose folds. The machine can be supplied with an Accumulator for continuous operation. Stenter are provided with very efficient un-curlers and Infra-Red Edge Sensors which actuate the in-feed device provided with Rack and Pinion system, ensuring perfect fabric holding in clips or pins even at high speeds exceeding 100 meters per minute.

Fabric Feeding System
Fig 2.3 Fabric Feeding System

2.6.1 (b) Over Feed
A simple and accurate over-feed system using Variable Frequency Drives with AC Geared Motors ensures perfect and precise Over-feed control as required by the fabric, ranging from -10% to +50% by control of motor speed. It is very simple and easy to maintain. A closed loop control system with encoder can be provided for precise control of the drives.

Fabric Over Feeding System
Fig 2.4 Fabric Over Feeding System

2.6.1 (c) Weft Shrinkage
Conicity of rails can be easily obtained by acting upon the individual width controlling screws of each compartment, de-clutching the individual unit from the main width adjustment control system and adjusting the individual rail to precise requirements, by acting upon each gear box provided on individual adjusting screw with the help of a hand-wheel. A suitable indication is provided on each gear box for precise control. It can also be automatically regulated as pre-programmed by acting on individual motors, with PLC Control.

2.6.1 (d) Width Adjustment
Stenter machine is equipped with a standard motorized width adjustment device with common shaft with gear boxes mounted on top of the dryer. The width adjustment device is controlled from the control desk by means of push buttons. Setting of individual screws can be done by means of a hand wheel acting through the clutch on individual gear boxes. It can also be equipped with individual motors and controllers for the individual screws which are controlled from the control desk either individually or all at a time. A suitable indicating arrangement is provided on the Operator Console.

2.6.2 COMPACTOR MACHINE
The length of loop in the grey fabrics decides the changes in the dimensional aspects of the knitted fabric during compaction. The change in courses per cm after compacting appears to be a function of the number of courses present in the original structure of the fabric. During the compaction process, the increase in courses per unit length results in decrease in the wales per unit length, resulting in a relatively dimensionally stable structure. In all the cases, corresponding to increase in the courses per cm a similar trend was also observed in the wales per cm after compacting. In case of rib fabric, decrease in the wales per cm was observed higher in which the increase in course per cm was higher among all the specimens.

Though the compacting process results increase in courses per unit length, the weight of the fabric per unit length (GSM), after compacting, is supposed to be same due to decrease in the wales per unit length, for a given linear density of the yarn. In case of rib structure, increase in the weight after compacting process remain lower compared to the other two structures, perhaps, due to higher decrease in the wales direction compared to the course direction. Though rib structure registered higher increase in courses per cm after compacting, the reduction wales per cm after compacting was also very much higher (17.9%) compared to interlock (4.8%) and single jersey (4.7%). The increase in fabric weight was found to be around 1.53%, 1.1% and 0.8% for single jersey, interlock and rib, respectively.

Fabric Path of Compactor
Fig 2.5 Fabric Path of Compactor

3. METHODOLOGY

3.1 RAW MATERIALS AND EQUIPMENT USED

3.1.1 RAW MATERIALS
The following raw materials are used-

Fabric: Grey knitted fabric (Interlock, 1×1 Rib, Single Jersey)

3.1.2 EQUIPMENTS
The following equipments are used-

Major equipments which are used for the thesis program is expressed in table-3.1

Machine Model No Serial No Origin
GSM Cutter MND4-B26 INDIA
Electronic Balance AB412 8028141017 OHAUS, Corporation, USA
Conditioning m/c CON2544 TAIWAN

Table 3.1 List of major equipments

3.2 METHODOLOGY
In order to determine the variation of knit fabric the GSM  was analyzed in different stages. The fabrics were produced from different count of yarns (26s, 32s, and 34s) and also with different stitch length. Our inspected fabric was dyed in dyeing m/c of different capacity. Then the fabric was dried with Stenter m/c in required temperature. Then compacting was done in compactor.

Selection of Fabric before Dyeing

↓→Measure the GSM

Pre-treatment process of the selected fabric

↓→Measure the GSM

Dyeing of the fabric

↓→Measure the GSM

Finishing of the fabric in Stenter

↓→Measure the GSM

Finishing of the fabric in Compactor

↓→Measure the GSM

GSM variation measurement & analyze the results

3.3 SELECTION OF FABRIC BEFORE DYEING
We study on three different knit structured fabric including different GSM. They are

  1. Interlock knit structured fabric
  2. 1×1 Rib knit structured fabric
  3. S/J (100% cotton) knit structured fabric

Fabric are selected before dyeing.Then a sample is taken from the Fabric & it is conditioned in standard atmosphere. Then the GSM was measured.

3.4 PRE-TREATMENT & DYEING OF THE SELECTED FABRIC
After selecting the sample fabrics each samples were scoured & dyed. Dyeing was carried out in FONG’S dyeing m/c having capacity of 25 kg.

3.5 DYEING M/C SPECIFICATION

  • Name of the M/C                     : Fong’s
  • Origin                                       : Hong Kong
  • Capacity                                   : 25Kg
  • No. of Nozzle                           : 01
  • Temperature                             : High temperature m/c
  • Pressure                                    : 06 Bar
  • Dosing tank                              : 01

The sample was collected after scouring & dyeing. Then after drying in dryer & conditioned in standard atmosphere. After then the GSM was measured.

3.6 FINISHING OF THE FABRIC IN STENTER

MECHANISM: The main mechanism of the Stentering machine, under feed roller to feed the fabric, over feed roller to increase and decrease GSM, spending roller to remove the crease mark, to adjust the bowing angle, Fabric wheel to stretch the fabric and contact with chain.

3.6.1 TECHNICAL DATA OF STENTER

Roller Width 1500 mm to 3800 mm
Fabric Width 1200 mm to 3600 mm
Mangle Two Bowl or Three Bowl
Fabric Feeding Draw 1 kW / 1.5 kW
Mangle Motor 5.6 / 7.6 / 11 kW
Top Roller 305 mm Diameter
Driven Roller 295 mm Diameter
Bottom Roller 305 mm Diameter
Guide Roll Diameter 114 mm / 141 mm / 152 mm / 177 mm (Wider Width)
Weft Correction Motorized Manual OR Fully Automatic Electronic
Stenter From 3 Chamber to 10 Chamber Pin-Clip Chain, Clip Chain, Pin Chain Vertical Return Pin Chain execution
Heating Media Thermic Oil / Direct Gas / Steam
Selvedge Tension 1.5 kW / 2.2 kW AC
Over-feed Motor 1.5 kW AC
Pinning Motor 0.75 kW AC
Blower Motor 5.6 kW / 7.6 kW / 11 kW
Thermic Fluid Heater
Natural Gas / LPG
10/12 Pass OR90,000 Kcal to 1,50,000 Kcal (2 per Chamber)
Variable Frequency AC Drive
Exhaust Two, Three or Four with / without moisture controller

3.6.2 STANDARD PARAMETER FOR STENTER MACHINE

Fabric Type GSM Dia Temp Over Feed Padder Pressure Speed Blower
S/L 115-150 2″(+) 110-140ºc 45-50% 2    bar 20-25 60-70
S/J 160-220 2″(+) 120-170ºc 45-50% 2.5 bar 18-23 65-75
1×1Rib 160-220 2″(+) 130-160ºc 50% 2 bar 24-28 70-80
Interlock 190-220 3″(+) 130-160ºc 50% 2 bar 20-25 70-80

Table 3.2 Standard parameter for Stenter m/c.

According to the required GSM, the GSM is controlled in the Stenter m/c. The maximum acceptable limit in Stenter is less than 10% than the required GSM.  The sample was collected after Stentering. Then conditioned in standard atmosphere. After then the GSM was measured.

3.7 FINISHING OF THE FABRIC IN COMPACTOR

MECHANISM: The mechanism of the compactor machine is classified in four sections. The function of compactor is to drive the fabric forward with stretch and at an angle to control the fabric as required length and spirality. The overfeed mechanism to increase & decrease the GSM & dia of the fabric. Here also steam is applied to soft the fabric. This is the third section of the machine it’s also called the compaction station (blanket). Here to control the GSM & calendaring the fabric surface.

3.7.1 COMPACTOR M/C SPECIFICATION

  • Over feed                                : Max + 35%, Min -35%.
  • Machine speed                        : Max 32m/min, Min 4m/min.
  • Temperature range                  : 100-2000C
  • Maximum width                     : 240cm
  • Minimum width                      : 100cm
  • Applied for                             : Open fabric
  • Left over feed                         : -20%®+20%
  • Right over feed                       : -20%®+60%
  • High production                      : -20%®+60%
  • Front over feeding cylinder    : -20%®+60%
  • Middle belt                             : -20%®+60%

3.7.2 MAIN PARTS OF THE COMPACTOR M/C

  1. Heating chamber
  2. Blower (2, one at the entry chain zone for uncurling and another at the entry of compacting zone)
  3. Synthetic blanket as a conveyor,
  4. Folder
  5. Exhaust fan
  6. Unpinning cylinder (-40%®+40%)
  7. Belt cylinder (-40%®+40%)
  8. Uncurling device at entry of compacting zone.
  9. Sensor
  10. Brush roller

3.7.3 EFFECT OF COMPACTION

Loop condition after compaction
Fig 3.1 Loop condition after compaction

3.7.4 STANDARD PARAMETER FOR COMPACTOR

Fabric Type Color Speed Over feed Temp Teflon Pressure
S/J White 15-18 60 90-100ºc 16-18(PSI)
Color 15-20 60 120-130ºc
1×1 RIB White 15-20 50-60 100-110ºc 16-18(PSI)
Color 15-20 110-120ºc
Interlock White 12-16 50-60 100-110ºc 16-18(PSI)
Color 12-16 110-120ºc

Table 3.3 Standard parameter for compactor.

According to the required GSM, the GSM is controlled in the compactor m/c. The maximum acceptable limit in compactor is less than 5% than the required GSM.  The sample was collected after compacting. Then conditioned in standard atmosphere. After then the GSM was measured.

4. RESULTS AND DISCUSSION
The objectives of this study were to evaluate the variation in different stages on GSM of cotton knit fabric. In this chapter, the variation is measured for same & different constructed fabric for different GSM in various stages of dyeing & finishing. We also analyzed the variation in same stage for different fabric. Moreover the effects were discussed separately and also analyzed. All measurements were performed under standard textile testing conditions of 20°C ± 1°C, and 65% ± 2% relative humidity. No tension was applied to samples during measuring GSM. The influence of parameters linked to yarn, fabric structure and machine were studied.

4.1 GSM – AT DIFFERENT KNIT FABRIC STRUCTURE
In this study the table (fig. – 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9) show plots of GSM variation for Interlock, 1×1 Rib, single-jersey fabrics knitted from 34S, 32S and 26S count of spun yarns at various GSM. In a more tightly knitted fabric, the movement of a knitted loop is restricted, and thus GSM is increased.

Among various analyzed knitted fabrics, the stitch length appears to be the important factor among all the structural parameters involved in the fabric construction. After analyzing a good relation was obtained between the stitch length & GSM & Count of the fabric.

4.1.1 VARIATIONS FOR INTERLOCK STRUCTURE
Interlock fabric samples were knitted from 100% carded cotton yarn of 34 Ne in three different GSM (170,190,204). The result of average GSM is shown in the graph below.

Graphical presentation of variation in GSM for Interlock Structure in different stages
Fig 4.1 Graphical presentation of variation in GSM for Interlock Structure in different stages

It has been found that the fabric is knitted at a GSM below the required value. Due to scouring, GSM is increased and after dyeing it goes down below the required value. But the required value is achieved through the after dyeing process such as Stentering & Compacting. It is also seen that the Finished GSM is in required acceptance level (±5%).

4.1.2 VARIATIONS FOR 1×1 RIB STRUCTURE
1×1 Rib fabric samples were knitted from 100% carded cotton yarn of 32 Ne in three different GSM (175,190,200). The result of average GSM is shown in the graph below.

Graphical presentation of variation in GSM for 1×1 Rib Structure in different stages
Fig 4.2 Graphical presentation of variation in GSM for 1×1 Rib Structure in different stages.

It has been found that the fabric is knitted at a GSM slight below the required value. Due to scouring, GSM is increased and after dyeing it goes down below the required value. But the required value is achieved through the after dyeing process such as Stentering & Compacting. It is also seen that the Finished GSM is in required acceptance level (±5%).

4.1.3 VARIATIONS FOR S/J STRUCTURE
S/J fabric samples were knitted from 100% carded cotton yarn of 26 Ne in three different GSM (137,150,170). The result of average GSM is shown in the graph below.

Graphical presentation of variation in GSM for S/J (100% cotton) Structure in different stages.
Fig 4.3 Graphical presentation of variation in GSM for S/J (100% cotton) Structure in different stages.

It has been found that the fabric is knitted at a GSM below the required value. Due to scouring, GSM is increased. But as S/J is thin in structure the GSM is upper than the required value. By Stentering the GSM controlled in a acceptable level for Stentering. After than the required value is achieved through the Compacting process. It is also seen that the Finished GSM is in required acceptance level (±5%).

4.1.4 VARIATIONS FOR INTERLOCK, 1×1 RIB & S/J STRUCTURE
In this experiment three samples were knitted from 100% carded cotton yarn of three different fabrics and the GSM of each sample was measured and the average was plotted into the chart.

Graphical presentation of variation in GSM for Interlock, 1×1 Rib & S/J (100% cotton) Structure in different stages.
Fig 4.4 Graphical presentation of variation in GSM for Interlock, 1×1 Rib & S/J (100% cotton) Structure in different stages.

Interlock & 1×1 Rib are more compact than the S/J fabric. But in Interlock structured fabric GSM increase after dyeing more  rapidly then the Rib structured fabric. As S/J fabric are thin in structure, after dyeing the GSM fall & it increase in Stentering stage.

The GSM increase almost 16.5% after scouring for Interlock fabric than before dyeing where as  the GSM increase almost 11%  for 1×1 Rib fabric & almost 25% for S/J fabric.

It is also analyzed that after Stentering the GSM increase around 7% of Interlock fabric than before dyeing & around 2% for 1×1 Rib fabric. But the GSM decrease around 6% for S/J fabric.

4.1.5 COMPARATIVE VARIATION OF REQUIRED GSM AT ‘BEFORE DYEING’ STAGE
The GSM of the samples for three different fabrics (Interlock, 1×1 Rib, S/J) were measured in ‘Before Dyeing’ Stage & the change in percentage in respect to ‘Required GSM’ was shown on the graph below.

Required GSM’ in respect to ‘Before dyeing GSM’
Fig 4.5 ‘Required GSM’ in respect to ‘Before dyeing GSM’

The figure shows that the Change of GSM in percentage at ‘Before Dyeing’ process in respect to ‘Required GSM’ is more in Interlock Fabric & S/J Fabric very low in the 1×1 Rib Fabric. It is also analyzed that Interlock fabric are more compact & S/j are less compact in knit structure. Though they are approximately show same change in percentage. But in 1×1 Rib fabric, the ‘Before Dyeing GSM’ is more close to ‘Required GSM’ than the other structured fabric.

4.1.6 COMPARATIVE VARIATION OF REQUIRED GSM AT ‘AFTER SCOURING’ STAGE
The GSM of the samples for three different fabrics (Interlock, 1×1 Rib, S/J) were measured in ‘After Scouring’ Stage & the change in percentage in respect to ‘Required GSM’ was shown on the graph below.

‘Required GSM’ in respect to ‘After Scouring GSM’
Fig 4.6 ‘Required GSM’ in respect to ‘After Scouring GSM’

The figure shows that the Change of GSM in percentage in ‘After Scouring’ process in respect to ‘Required GSM’ is more in S/J Fabric than lower in 1×1 Rib Fabric & the lowest in Interlock Fabric. It is also noted that the change in percentage in respect to ‘Required GSM’ is negative. That means ‘After Scouring GSM’ increases than ‘Required GSM’.

4.1.7 COMPARATIVE VARIATION OF REQUIRED GSM AT ‘AFTER DYEING’ STAGE
The GSM of the samples for three different fabrics (Interlock, 1×1 Rib, S/J) were measured in ‘After Dyeing’ Stage & the change in percentage in respect to ‘Required GSM’ was shown on the graph below.

‘Required GSM’ in respect to ‘After dyeing GSM’
Fig 4.7 ‘Required GSM’ in respect to ‘After dyeing GSM’

The figure shows that the Change of GSM in percentage at ‘After Dyeing’ process in respect to ‘Required GSM’ is more in Interlock  Fabric & lower in 1×1 Rib Fabric & very low in S/J Fabric. It is incorporated that the variation after dyeing of Interlock fabric is more than the other. So the GSM is fully controlled & have to give more attention in Stentering stages. The GSM of S/J fabric varies closely in its subsequent stages.

4.1.8 COMPARATIVE VARIATION OF REQUIRED GSM AT ‘AFTER STENTERING’ STAGE
The GSM of the samples for three different fabric (Interlock, 1×1 Rib, S/J) were measured in ‘After Stentering’ Stage & the change in percentage in respect to ‘Required GSM’ was shown on the graph below.

‘Required GSM’ in respect to ‘After Stentering GSM’
Fig 4.8 ‘Required GSM’ in respect to ‘After Stentering GSM’

The figure shows that the Change of GSM in percentage at ‘After Stentering’ process in respect to ‘Required GSM’ is more in S/J Fabric than 1×1 Rib Fabric & Interlock Fabric. It is also observed that change of Interlock & 1×1 Rib Fabric is almost same as they are closely knitted structure.

4.1.9 COMPARATIVE VARIATION OF REQUIRED GSM AT AFTER COMPACTING STAGE
The GSM of the samples for three different fabrics (Interlock, 1×1 Rib, S/J) were measured in ‘After Compacting’ Stage & the change in percentage in respect to ‘Required GSM’ was shown on the graph below.

‘Required GSM’ in respect to ‘After Compacting GSM’
Fig 4.9 ‘Required GSM’ in respect to ‘After Compacting GSM’

The figure shows that the Change of GSM in percentage at After Compacting’ process in respect to ‘Required GSM’ is almost equal in S/J Fabric & 1×1 Rib Fabric. The change is slight less in Interlock Fabric. So more compaction should be given to 1×1 Rib & S/J fabric than Interlock fabric.

4.2 DISCUSSION
The project of our work is to measure the variation in different processing stages of dyeing & Finishing and analyze the results. There are problem in our industries to produce knitted fabrics of required G.S.M. Other specification like fabric width, fabric thickness is generally maintained in industries by previous data sheet. For this reason there are problem if any order comes which didn’t produced in previous.

The standard measurement for weight and quality of fabrics is grams per square meter, usually abbreviated as GSM. This is the accepted standard in the United States as well as in foreign countries. The Grey GSM (Grams per square meter) is a very important parameter for specified a certain quality of knitted fabric. The production of knitted fabric is calculated in weight. The production cost and selling and purchasing representing a certain quality of knitted fabric.

In this study some experimental results shows that, GSM of knitted fabrics increase in Scouring stages. It is because the acceptance of chemical is more in fabric after scouring.

5. CONCLUSION

5.1 CONCLUSION
This study presents an experimental investigation of the variation of GSM in different stages of textile processing specially in dyeing and finishing on Interlock, 1×1 Rib, S/J fabric. It is observed that in the scouring stages contain the most significant effect on GSM of Interlock, 1×1 Rib, S/J fabric. At the same way the fabric construction also influences the GSM of cotton knitted fabric. In most cases, it is clear that GSM increases with the increment of different stages with a linear line with some exceptions. Further study should be done for variation on GSM for cotton knit fabric of different constructions except Interlock, 1×1 Rib, S/J fabric.

5.2 FINDINGS
In our study the following findings were found:

  1. Firstly, all types of fabric are knitted in lower GSM value than the Required.
  2. After Scouring, GSM increased & after Dyeing & Finishing, GSM decreased.
  3. After unloading fabric from dyeing m/c, the required value of GSM is obtained by increasing the GSM through Drying & Compacting process.

6. REFERENCES

  1. Shah, D.L.; “Latest Techniques of Processing Knit Fabrics Containing Elastomeric for Fashion Garments”, Man–Made Textiles in India, vol. 12, 2003, pp. 3–8.
  2. Saufley C.E.; “Continuous Finishing of Circular Knit Fabrics”, AATCC Review, vol. 24, no 3, 1992, pp. 17–19.
  3. Bourah R K.; “Process Control in Circular Knitting Plant”, Textile Committee, vol. 2, 2004, pp. 26–31.
  4. Tendulkar, S.R. and Kulkarni, G.N.; “Improved Methods of Hosiery Processing”, Textile Dyer and Printer, vol. 16, March, 1994, pp. 25–29.
  5. Euscher, G. and Jayachandran, S.; “Knit Goods Processing”, Indian Textile Journal, vol. 4, 1997, pp. 19–21.
  6. Baser, G. and Çeken, F.; 1985, E.U. Müh. Fak. Dergisi, Volume: 3, pp. 2.
  7. De Araujo, M.D. and Smith, G.W.; 1989, Textile Research Journal, 59, pp. 247-256.
  8. Tao, J., Dhingra, R., C., Chan, C., K., Abbas, M.,S.; “Effects of yarn and Fabric construction on spiralitv of Cotton Single Jersey Fabrics”, Textile Research Journal, 67, 57-68. 1997.
  9. Abdel-Megied, Z.M. and bakry Ahmed E.L.; “The effect of Machine Setting On Weft- Knitted Fabric properties”, Journal of Applied Sciences Research, 4(11): 1371-1379, 2008.
  10. Anon.; “Dewatering and Overstretching Machine for Finishing of Knitted fabrics”, Express Textiles, vol. 22, February 2001.
  11. Saravanan, D.N.B., Timble, Gunasekar, E., Kandasamy, V.A.; “Influence of Compacting on Knitted Fabrics”, IE (I) Journal–TX pp, 15. Vol. 88, February 2008.
  12. SPENCER, J, DAVID.; “Knitting Technology”, Second Edition, 1989.

APPENDIX A

A.1 GSM data variation on different knit Fabric structure

A.1.1 Variation for Interlock Fabric in different stages

Fabric type Sample No. Count GSM before dyeing After scouring After dyeing After Stenter After compacting Required GSM
 

Interlock

1.  

34s

170 200 172 180 185 190
2. 190 212 185 205 215 220
3. 204 245 200 212 220 230

Table A.1 GSM variation for Interlock Fabric in different stages

A.1.2 Variation for 1×1 Rib Fabric in different stages

Fabric type Sample No. Count GSM before dyeing After scouring After dyeing After Stenter After compacting Required GSM
 

1×1 Rib

1.  

32s

175 200 170 172 175 180
2. 190 208 182 185 192 200
3. 200 218 190 195 200 210

Table A.2 GSM variation for 1×1 Rib Fabric in different stages

A.1.3 Variation for S/J (100%cotton) Fabric in different stages

Fabric type Sample No. Count GSM before dyeing After scouring After dyeing After Stenter After compacting Required GSM
S/J (100%cotton) 1.  

26s

137 180 150 145 152 160
2. 150 180 165 160 168 170
3. 170 210 179 160 170 180

Table A.3 GSM variation for S/J (100%cotton) Fabric in different stages

APPENDIX B

B.1 GSM data variation on Different stages of processing

B.1.1 Variation for Interlock, 1×1 Rib & S/J(100%cotton) Fabric at ‘Before Dyeing’ stage

Fabric type Interlock 1×1 Rib S/J (100%cotton)
Sample 1 Sample 2 Sample 3 Sample 1 Sample 2 Sample 3 Sample 1 Sample 2 Sample 3
Count 34s 34s 34s 32s 32s 32s 26s 26s 26s
Before dyeing GSM 170 190 204 175 190 200 137 150 170
Required GSM 190 220 230 180 200 210 160 170 180

Table B.1 GSM variation for Interlock, 1×1 Rib & S/J (100%cotton) Fabric at ‘Before Dyeing’ stage

B.1.2 Variation for Interlock, 1×1 Rib & S/J(100%cotton) Fabric at ‘After Scouring’ stage

Fabric type Interlock 1×1 Rib S/J (100%cotton)
Sample 1 Sample 2 Sample 3 Sample 1 Sample 2 Sample 3 Sample 1 Sample 2 Sample 3
Count 34s 34s 34s 32s 32s 32s 26s 26s 26s
After scouring GSM 200 212 245 200 208 218 180 180 170
Required GSM 190 220 230 180 200 210 160 170 180

Table B.2 GSM variation for Interlock, 1×1 Rib & S/J (100%cotton) Fabric at ‘After Scouring’ stage

B.1.3 Variation for Interlock, 1×1 Rib & S/J (100%cotton) Fabric at ‘After Dyeing’ stage

Fabric type Interlock 1×1 Rib S/J (100%cotton)
Sample 1 Sample 2 Sample 3 Sample 1 Sample 2 Sample 3 Sample 1 Sample 2 Sample 3
Count 34s 34s 34s 32s 32s 32s 26s 26s 26s
After dyeing GSM 172 185 200 170 182 190 150 165 179
Required GSM 190 220 230 180 200 210 160 170 180

Table B.3 GSM variation for Interlock, 1×1 Rib & S/J(100%cotton) Fabric at ‘After Dyeing’ stage

B.1.4 Variation for Interlock, 1×1 Rib & S/J (100%cotton) Fabric at ‘After Stentering’ stage

Fabric type Interlock 1×1 Rib S/J (100%cotton)
Sample 1 Sample 2 Sample 3 Sample 1 Sample 2 Sample 3 Sample 1 Sample 2 Sample 3
Count 34s 34s 34s 32s 32s 32s 26s 26s 26s
After Stenter GSM 180 205 212 172 185 195 145 160 160
Required GSM 190 220 230 180 200 210 160 170 180

Table B.4 GSM variation for Interlock, 1×1 Rib & S/J (100%cotton) Fabric at ‘After Stentering’ stage

B.1.5 Variation for Interlock, 1×1 Rib & S/J (100%cotton) Fabric at ‘After Compacting’ stage

Fabric type Interlock 1×1 Rib S/J(100%cotton)
Sample 1 Sample 2 Sample 3 Sample 1 Sample 2 Sample 3 Sample 1 Sample 2 Sample 3
Count 34s 34s 34s 32s 32s 32s 26s 26s 26s
After compacting GSM 185 215 220 175 192 200 152 168 170
Required GSM 190 220 230 180 200 210 160 170 180

Table B.5 GSM variation for Interlock, 1×1 Rib & S/J (100%cotton) Fabric at ‘After Compacting’ stage

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