Friday, June 22, 2012

CLASSIFICATION OF FIBRES


Cotton
Jute
Hemp
Flax / Linen
Bamboo
(Natural)

Wool
Silk

Glass
Asbestos
Metal
Ceramic


Polyester
Polyamide
(Nylon)
Acrylic
Polyolefin
Spandex / Elastane
(Lycra )

CELLULOSE BASED
Viscose Rayon
Cupra Rayon
Acetate Rayon
Bamboo Viscose
Modal
Lyocell (Tencel)
PROTEIN BASED
Protein ( Soya )

Monday, June 18, 2012

Pigment Dyeing in Winch Machine






CATIONIZATION
 


M:L-1:20
 




M/C fill with water
 
 




Scoured fabric Load & set PH at 8.5
 
 




Add For Foam NS/Anti Foam
 
 




Run time 5min
 
 




Temperature raise to 75ºC
 
 




Dosing For Cat NCH at 70% for 50min
 
 




Run time 20min
 
 




Cold rinse 5´min at 40ºC
 
 








                Drain
 



M/C fill & cold rinse 5min at 40ºC
 




                Drain
 




DYEING
 




M/C fill with water
 




Add For Foam NS
 




Temperature raise to 75ºC
 




Color dosing 50min at 70%
 




Run time 20min
 
 

























Drain
 


 














Thursday, June 14, 2012

Problems found in Finishing in Knit Dyeing


There are many many problems,out of them the followings are important-
01. GSM problem (High or Low)
02. Shrinkage (Above limit)
03. Dia(less/More)
04. Spirality(High)
05. Softener Spot
06. Soda Spot
07. Yellow Spot
08. Band Mark or Band Line
09. Crease Mark
10. Neps
11. Hairiness
13. Dia Mark
14. Hole
15. Sinker Mark
16. Uneven or Patchy dyeing
17. Running Shade
18. Roll to roll shade variation
19. Bowing
20. Lycra Missing
21. Fabric Strength fall
22. Shade not matching with standard
23.ETC.
24. And finally not going delivery on-time to cutting for above mentioned reasons. 

Monday, June 11, 2012

Dyeing Procedure

Filling at 50 degree C

Chemical Inject (Detergent+Sequestering+Anti creasing)

Loading Fabric

Caustic Dosing at 50 degree C

Peroxide Dosing at 50 degree C

Raise Temperature (80-95 deg C)

Runtime (45-60 Min)

Drain

Hot wash at 90 degree for 10 minutes

Rinse for 5 minutes

Acid at 60 degree C

Fill

pH Setting for Enzyme at 4.5-5.5 or (6 for dye bath enzyme)

Runtime 55 deg C*60 min

Raise Temperature 70

Runtime 5-10 min

Drain

Rinse for 5 min

Dyebath set for dyeing

pH 6.0-6.5

Salt or Color dosing(color-20-40 min/salt-inject/5 min)

Color or Salt Dosing

Runtime-30 min

Soda dosing(20-40 min)

Raise Temperature at 60-80 degree C

Dyeing----------

Shade Check 10 min----30 min----50 min....................

Shade ok

Bath Drain

Rinse upto color remains

Acid at room temperature

Wash with Wash off---80-90 deg C for 10 min

if shade is ok then

Fixer (if necessary) 40 degree for 20 min

Softener 40 degree C for 20 min

Finishing

Squezzer/Slitting/Hydroextactor

Flat dryer/Stenter

Quality Checking (if OK) (Quality-Dia/Shrinkage/GSM/Spirality/Fabric levelness etc.)

Tube/Open compacting

Quality Checking)

Dispatch to Cutting

GSM

Name of the Experiment: Determination of GSM of woven and knitted fabrics.


Introduction:
The GSM of fabric is one kind of specification of fabric which is very important for a textile engineer for understanding and production of fabric. ‘GSM’ means ‘Gram per square meter’ that is the weight of fabric in gram per one square meter. By this we can compare the fabrics in unit area which is heavier and which is lighter. 


GSM Cutter
Objectives:
  1. To determine the GSM of the given samples of fabric.
  2. To compare the GSM of them.
Theory:
The weight of a fabric can be expressed in two ways, either as the ‘weight per unit area’ or the ‘weight per unit length’; the former is self explanatory but the latter requires a little explanation because the weight of a unit length of fabric will obviously be affected by its width. In woven fabric, the weight per unit length is usually referred to as the ‘weight per running yard’. It is necessary therefore to know the agreed standard width upon which the weight per running yard is based. Usually this width depends upon the width of loom. Before coming the term ‘GSM’ there was another term called ‘lb/100 yards’. This expression is used by British Standard. For measuring this there are a template and a quadrant balance. The template area is 1/100 square yards of which each arm is 1/10 yards in length. For measuring GSM, a GSM cutter is used to cut the fabric and weight is taken in balance. Both of these measurement and method is equally used for both woven and knitted fabrics.

Apparatus:

  1. Template
  2. Quadrant balance
  3. Scissor
  4. GSM cutter
  5. Electric balance.
Sample:
  1. Finished cotton woven fabric
  2. Finished cotton knitted fabric.
Atmosphere:
Temperature – 25oC and relative humidity – 67%
Standard atmosphere: temperature – 20oC and relative humidity - 65%.

M/c specification:
Name: Quadrant balance
Brand: Good brand & Co. Ltd.
Scale: 100 yards for fabric.

Working Procedure:

  1. For measuring with Quadrant balance, at first we should cut the fabric sample according to the template area. By this way we cut 10 woven samples and 10 knitted samples.
  2. Now weigh these samples in pounds by quadrant balance according to 100 yards scale.
  3. By this way we get the weight in pound per 100 square yards fabric.
  4. For Measuring GSM, we should cut the fabric sample by GSM cutter. By this way cut 10 woven samples and 10 knitted samples.
  5. Now weigh these samples by electric balance in grams.
  6. By this way we get the weight in gram per one square meter fabric.
  7. Now find out the average of these found weights.
  8. For woven fabrics find out the weight per running yards assuming the loom width 48 inches.
Data: 

Type
Woven Fabric
Knitted fabric
Sl No.
lb/100 yd2
gm/meter2
lb/100 yd2
gm/meter2
1
20
107.64
38
144
2
19
107.64
37
144
3
19
104.75
35
149.67
4
19
102.86
38
143.81
5
18
102.86
36
148
Average
19.2
106.83
36.8
145.37

Calculation:
For measuring the weight of woven fabric in weight per running yards, form data table we get the weight of 100 yd2 fabric is 19.2 lbs. Now assume the width of loom is 48 inches. Therefore the area of the fabric will be 1.33 yd2. So,

Weight of 100 yd2 woven fabric = 19.2 lbs. 
Weight of 1.33 yd2 woven fabric =  0.255 lbs.

That is weight of fabric per running yard is 0.255lbs or 116 gms.

Result:

  1. The weight of woven fabric is 19.2 lbs/100 yd2 or 106.83 GSM.
  2. The weight of knitted fabric is 36.8 lbs/100 yd2 or 145.37 GSM.
  3. The weight of woven fabric per running yard is 0.255lbs or 116 gms.
Remark:
This is a direct measuring tester. So the result should be accurate. But as the samples are of both cotton fabrics, so there are effects of moisture content on the weight of fabrics. Besides the knitted fabrics are very much extensible and proper relaxed state is quite different during cutting of sample with GSM cutter. Therefore there are variations among their weights. The effects of moisture content can be accounted for either by conditioning the specimen in the standard atmosphere or by taking the specimen to oven dry weight and adding the official regain. 

 

Grey GSM VS Finished GSM of knit fabric

Learn Apparel Merchandising, Learn Fashion design.


After received the yarn we knit the yarn in knitting machine for producing knit fabric. In this stage the fabric remain uncolor formed. We called this as Grey Fabric. Then we dye the grey fabric in dyeing winch (machine) as per our required color.
In this regards the please not that, GSM of the followings Grey fabric are not remain same as our require finished fabric GSM. Normally the GSM of grey fabric remain lower then the finished fabric. After knitting when we dye and washed the fabric then the GSM increase and come to near as our requirement. This increasement of GSM depends on fabric constructions & some knitting variables. Lets see an example
Say,
Fabric Construction: Single Jersey
Yarn Count : 30/s
Require GSM(finished): 145 GSM
Grey GSM : will be what?
As per practical experience we know for Single Jersey fabric, if we knit the fabric with 30/s yarn then the grey GSM  will increase 15% to 20% after dyeing and finishing.
So, if we need 145 GSM S/J fabric with 30/s
Then we should keep the
Grey GSM = 145 – (15 to 20%), supposed it the percentage will be 18 then
Grey GSM = 145 – 18%
Grey GSM = 119 GSM
So, now we know that, if we need 145 gsm single jersey fabric with 30/s yarn, then we should keep the GSM of grey fabric as 119.
Please find below the GSM differents between Grey VS Finished for some more types of fabric.
  
For single jersey fabric:
If the yarn count is 30/s then the grey gsm will be 20% to 15% less from the finished Gsm
If the yarn count is 26/s then the grey gsm will be 22% to 20% less from the finished Gsm
If the yarn count is 24/s then the grey gsm will be 24% to 23% less from the finished Gsm
If the yarn count is 20/s then the grey gsm will be 24% to 21% less from the finished Gsm


G.S.M Calculation
GSM means grams per square meter. In knitting fabric it is the main parameter. It is controlled by loop length. If loop length increases GSM will decrease and vice versa. It is measured by GSM cutter & electric balance. It may also be calculated as below. 


G.S.M calculation

             s x l x tex
GSM = ……………
                100

             s x l x 590
GSM = ……………
                  Ne

Calculate GSM of fabric from the given data:

  • Total Weight of fabric = 15.5 Kgs
  • Length of fabric = 35 meters
  • Width of fabric in open form = 65 inches
Solution:

First we will calculate area of the fabric

Fabric length = 35 meters
Fabric width = 65 inches or 1.65 meters

Fabric area = Length x width
= 35 x 1.65
= 57.75 meters square

Weight of 57.75 Meter square is 15.5 kgs or 15500 grams

So weight of one square meter
= 15500 / 57.075

= 268.39 grams per square meter 


Fabric GSM is 268.39 (ANS)


Yarn Count S/J L/S/J5% L/S/J 8% Pique D/Lacoste Rib 1*1 Rib 2*1 Rib 4*2 L/Rib 1*1 L/Rib 2*2 I/L L/PK5% F/T L/F/T5% Waffle
GSM