LABORATORY CALCULATIONS & PROCEDRES

1
Engr. Abu Sayed, M.Sc in Textile Engineer, Email id- testleader9@gmail.com
DEDICATED TO
MY DEAR SIR MR. SAJESH PERINGETH
Abu Sayed Sajesh sir
ACKNOWLEDGEMENT
At first, I gratefulness goes to Almighty God to give us strength and ability to
understand good or bad. You have made our life more beautiful. May you name be
exalted, honored and glorified.
I am Abu Sayed, not big man but simple man. My home district is Tangail. I am proudful
that my father is a farmer. I have completed the M.Sc in Textile Engineering from
Daffodil Internatioanal University. I am working as laboratory Manager in a reputed
group at Narayanganj.
I want to give my heartiest gratitude to my dear sir Mr. Sajesh (Quality Assurance Manager).
Thanks goes to all Engineers, officers, technicians, employees, staff and all section in- charges
for their cordial behavior help.
SUMMARY
This Manual has arranged on the basis of Textile Dyeing lab procedure, calculations & ETP etc.
Here presenting some Lab & Dyeing calculations in my Practical life. I am not Writer & If I any
mistake, Excuse me. You mind it man is wrong.

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Lab Dip:
Lab Dip Development means the sample which is dyed according to buyer’s requirements
(similar shade and so on). Depending on lab dip development sample dyeing and bulk production
dyeing planning is done. Lab work plays an important role in dyeing process. Bulk dyeing
process completely depends on the lab dip development work. Lab work is completely managed
as the following sequence.
Lab dip is a process by which buyers supplied swatch is matched with the varying dyes
percentage in the laboratory with or without help of “DATA COLOR”.
Lab dip plays an important role in shade matching & and detaching the characteristics of the
dyes and chemicals are to be used in the large scale of production. So this is an important task
before bulk production.
Object of Lab Dip:
The main objectives in lab dip are as follows:
1. To calculate the recipe for sample dyeing.
2. To compare dyed sample with swatch by light Box or Spectrophotometer.
3. To calculate revise recipe for sample dyeing.
4. Finally approved Lab Dip (Grade: A, B, C & D)
Common Stock Solutions:
Red – 0.1%, 0.5%, 1.0%, 2.0% (very common)
Yellow – 0.1%, 0.5%, 1.0%, 2.0% (very common)
Blue – 0.1%, 0.5%, 1.0%, 2.0% (very common).
Preparation:
To prepare 0.1% Stock solution, it is necessary to mix 0.1 g dye and 100 cc water.
To prepare 0.5% Stock solution, 0.5 g dye stuff is mixed with 100 cc water.
To prepare 1.0% & 2.0% Stock solution similar procedure is followed.
To prepare 10% Stock solution of Soda ash, 10 g Soda is mixed with 100 cc water.
Depth of Shade:
0.5% to 5% shade for the goods.
Lab Dip Calculation:
Usually following calculations are followed:
Dye Solution = (Shade % * Sample Weight) / (Stock solution %) (cc).
Salt = (Shade % * Liquor) / 1000 (gram per liter, gpl).
Soda Solution = (Shade % * 100 * Liquor) / (1000 * Stock solution %) (cc).
Sample Calculation for 0.5% Shade:
Sample wt. = 5 mg
Material liquor ratio = 1: 10
Total liquor (5 * 10) = 50 cc
Dye solution required = (5 * 0.5%) / 1% = 2.5 cc
Salt solution required = (50 * 25) / (20 * 10) = 6.25 cc
Soda ash solution required = (50 * 10) / (20 * 10) = 2.5 cc
Water required = {50 – (2.5 + 6.25 + 2.5)} = 38.75 cc

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Working Procedure in Lab Dip:
All ingredients had been taken according to the recipe into the pot of sample dyeing machine. At
a room temp the material had run then after 10 minutes started to rise the temperature at 1°C/
min. to get 60°C temperature. For performing the required dyeing temperature it took 30
minutes. The material had dyed at 60°C for 45 minutes. Then the temperature was reduced at
room temperature within in 10 minutes. The fabric washed in cold water & then the material was
washed in 1 gm/l soap solution (liquor ratio 1:20) at 90°C temperature for 15 minutes. Then after
rapidly cold washing the material was dried & preserved. And then check the shade match with
the required sample by the lighting box. Then send to buyer or merchandiser for approval.
Working Procedure of Sample Dyeing (Knit Dyeing Section):
Normally a textile dyeing mill get offer through merchandiser. Merchandising department of
dyeing mill send the swatch to the central dyeing lab. Then the lab manager analysis the color of
swatch with the help of spectrophotometer. After shade matching three sample are submitted to
the buyer or buyer agents. If sample is approved by the buyer then this sample recipe are sent to
floor for bulk production. The dyeing master dyeing the sample for bulk production. Now I will
give the flowchart of sample dyeing for bulk production.
Sample dyeing machine
(Scouring and Bleaching)
Water load in sample dyeing machine
↓
Fabric load
↓
Temperature raised in 500
C
↓
Scouring chemical added (dosing time 10min)
↓
C
↓
NaOH dosing ( dosing time 5min)
↓
C
↓
Hydrogen Peroxide dosing (dosing time 10min)
↓
Temperature raised in 100-1100
C and running at 30min
↓
Cooling at 800
C
↓
Ringe or normal wash (10min)
↓
Drain out
↓
New water load

4
↓
C
↓
Add acid + OEM ( for destroying Hydrogen Peroxide power)
↓
pH check and obtain 4.5 by adding acetic acid
↓
Enzyme is added and run time 60 min
↓
Sample check if approved by incharge
↓
Ringe (run time 15min)
↓
Drain out
(Dyeing)
New water load
↓
pH check and obtain 5.6 by adding acetic acid
↓
Temperature raised at 50-550
C
↓
Dyeing auxiliaries added (leveling agent, anti creasing agent, sequestering agent etc)
↓
Salt added and running at 10min
↓
Color is added and dosing time 30 min ( Reactive dye, Disperse dye, Acid dye etc)
↓
Running time 25 min
↓
Temperature raised at 600C
↓
Soda ash (dosing time 35 min)
↓
Sample cutting for checking after 10 min later
↓
If approve then ringe at 20 min
↓
New water load
↓
Add acetic acid for neutralization at 400
C and run at 10min
↓
Ringe at 5 min
↓
Drain out

5
↓
New water load
↓
Temperature raised at 90-950
C and 10 min running
↓
Cooling at 800
C
↓
Ringe ( for cut sample)
↓
Shade checking if approve by incharge then
↓
Ringe and running at 15 min
↓
Drain out
↓
New water load
↓
Temperature raised at 300
C
↓
Fixing agent added ( GG-100, ECO, CR) and dosing time 10min
↓
Ringe ( 10min)
↓
Drain out
↓
New water load
↓
Temperature raised at 400
C
↓
Softener added and run time 30 min
↓
Shade matching if approve then
↓
Fabric unload.

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Cotton fabric dyeing by Reactive dyes
Sample weight = 5 gm.
M: L = 1: 10
Recipe:
Reactive dyes = 0.8 %
Salt = 30 g/l
Soda = 10 g/l
Calculations:
We know, Dyes = F. weight in gm x shade %
Stock solution %
Water = 50 ml.
Suppose, Stock solution = 1 %.
Reactive dyes = 5 gm x 0.8 % = 4 ml.
1 %
Reactive dyes = 5 gm x 1.0 % = 5 ml.
1 %
Reactive dyes = 5 gm x 0.05 % = 0.25 ml.
1 %
Salt = 30 g/l = 30 x 50 / 1000 = 1.5 gm.
Soda = 10 g/l = 10 x 50 / 1000 = 0.5 gm.
Total volume = 50 ml
Required water = 50 – (4+5 + 0.25) ml = 40.75 ml.
In dye pot, 5 gm sample + 4 ml +5 ml + 0.25 ml + 1.5 gm + 0.5 gm + 40.75 ml.
Time & Temperature = 60 min x 600
C.
FABRIC DYEING
Fabric dyeing is the method after weaving, knitting or non-woven to make fabrics. This is very
popular method of dyeing as the dyed fabrics will be processed further to garment industries very
easily. Dyeing forms of the fabric dyeing can be used in 2 ways.
1. Open width form using the fabrics to spread without any creases and dye them.
2. Rope form using the fabrics with the form like a rope.
Dyeing work flow chart:
Scouring & bleaching
↓
Per oxide hot with a/acid
↓
Enzymes wash with a/acid
↓
Leveling with sequestering
↓

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Dyeing dosing
↓
Salt dosing
↓
Soda dosing
↓
Sample
↓
Drain
↓
Washing off
↓
A/acid
↓
Softener
↓
Unload
Working Procedure:
Firstly the detergent, Anti-creasing agent, Anti-foaming agent and Stabilizer are mixed in mixing
tank, then load to machine at 50°c
↓
The temperature is risen to 60°c. Now the Caustic Soda is given to bath
↓
The Hydrogen Peroxide is given at 70°c
↓
Raise the temperature at 98°c and run for 60 minutes. Here the Ph = 11-12
↓
Rinse the fabric
↓
Hot wash is done at 80°c × 10 → Drain → Normal wash → Drain
↓
Peroxide is applied at 60°c and run for 15 minutes → Hot wash
↓
Add Acetic Acid at same temperature and run 10 minutes
↓
pH checked (pH=6.5) → Normal wash
↓
Now Acetic Acid applied at 55°c for pH control (pH= 4.50) and then Enzyme is given to bath at
same temperature with 60 minute
↓
Raise the temperature (Grade rate → 2 C/min) at 80°c and run 6 minute
↓
Cold wash is done 2 times and the drained out.

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Procedure for Lab dips by the Different Dyestuff in the Laboratory:
Procedure for100 % Cotton Fabric:
1. Calculate the recipe.
2. Weight the fabric.
3. Take the beaker keep the fabric in to the beaker.
4. Then the dyes, chemicals & required amount of water take in to the beaker by the digital
pipeting.
5. Then weight the salt by the electric balance and add in to the beaker.
6. Then the beaker set in to the lab dyeing machine for dyeing.
7. Start the program for dyeing the whole dyeing time 60 min at 60 °C temperature. ( the dyeing
time and temperature depends on which classes of dyes are used for dyeing .)
8. After 30 min add the then add the soda ash . by pipeting .
9. Again run the program next 30 min at the same temperature .
10. Finished the dyeing time then the sample taken from the beaker first hot wash & then cold
wash.
11. Then acid wash as for neutralization.
12. Then soaping required soap solution 10 min at 90° C temperature.
13. After the fabric again cold.
14. Then dry the lab dip and compare with the standard.
Turquoise Color:
Turquoise is the color of the gem turquoise. It is a slightly greenish shade of cyan. Turquoise is
sometimes described as a mixture of pale blue and green. The name comes from the French for
Turkish.
Turquoise Color
Types of Turquoise Color: There are six type of Turquoise Color. They are given below:
1. Pale Turquoise (web color) (Hex: #AFEEEE) (RGB: 175, 238, 238)
2. Turquoise Blue (Hex: #00FFEF) (RGB: 0, 255, 239)
3. Bright Turquoise (Hex: #08E8DE) (RGB: 8, 232, 222)
4. TURQUOISE (web color) (Hex: #40E0D0) (RGB: 64, 224, 208)
5. Medium Turquoise (web color) (Hex: #48D1CC) (RGB: 72, 209, 204)
6. Deep Turquoise (web color Dark Turquoise) (Hex: #00CED1) (RGB: 0, 206, 209)

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Process Flow Chart for 100% Cotton Knit Fabric (Turquoise Color):
Turquoise is very sensitive color. Its wash fastness is not good. Dyeing process of turquoise
color is slightly difference from other color process.
Process Sequence of Turquoise Color:
Fabric loaded
↓
Treating with anti-creasing agent (Room temperature)
↓
Adding detergent
↓
Adding Antifoaming agent
↓
Caustic dosing (dosing 6min)
↓
Peroxide dosing (60˚c; 5min)
↓
Run time 1 hour 95˚c
↓
Sample check
↓
If ok
↓
Drain out
↓
Normal hot (70˚c, 10min)
↓
Drain
↓
Adding Peroxide Killer
↓
Run time 55˚c, 10min
↓
Adding Acetic Acid
↓
Run time 10min 55˚c (ph-4.5)
↓
Adding enzyme
↓
Run time 1hour, 55˚c
↓
Enzyme hot- 70˚c, 10min

10
↓
Drain
↓
Filling in the tank (run time 5min)
↓
Rinsing -4min
↓
Drain
↓
Filling in the tank
↓
Adding Leveling, Antifoaming & Anti-creasing agent (R.T.)
↓
10min run time (R.T.)
↓
10min run time (60˚c)
↓
Color dosing-30min
↓
10min run
↓
½ Salt dosing-5min
↓
½ Salt dosing -5min
↓
Runtime -25min (60˚c)
↓
Sample check
↓
Soda dosing (2 g/l; 20min)
↓
Remaining Soda dosing (30min)
↓
20 min run
↓
Temp rise 80˚c
↓
Run time-1 hour
↓
Rinsing-5min
↓
Drain
↓

11
Filling in the tank
↓
Run time (RT)
↓
Drain
↓
Filling in the tank
↓
Normal hot (60˚c,10min)
↓
Sample check
↓
Drain
↓
Adding Acetic Acid (room temp, run time-30min)
↓
Sample check
↓
Drain
↓
Filling in the tank
↓
Adding soaping agent (90˚c, run-10 min)
↓
Drain
↓
Sample check
↓
Filling in the tank
↓
Rinsing (5min room tem)
↓
Drain
↓
Filling in the tank
↓
Run time (5min, room tem)
↓
Drain
↓
Filling in the tank
↓
Dosing-fixing agent (15min)

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↓
↓
Sample check
↓
Drain
↓
Filling in the tank
↓
Dosing softener (5min)
↓
↓
Sample check
↓
Unload.
Package Dyeing (HT HP) - Cheese Yarn Dyeing-II
Reactive Dyeing of cotton yarn in cheese form:
Whether it is Vinylsulphone or Bifunctional dyestuff, you may follow the following dyeing cycle
for yarn dyeing:
The Chemical table shown below contains a Code No. that has to be included time to time when
the dyeing process is going on.
Code No Name of Chemical Grams/liter
1
Acetic Acid 0.5
Sequestering Agent 0.5
2
Acetic Acid 0.5
Vacuum Salt or Glauber's Salt As Recommended
3 Dyestuff O.W.F.
4 Soda Ash As Recommended
5 Acetic Acid 0.5
6
Sequestering Agent 0.5
Anionic Soap 0.5
7 Acetic Acid 0.5
8 Dye fixing Agent Not Necessary
9 Softener 1.0

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Processing Cycle for Yarn Dyeing:
 Set the dye bath with soft water at ambient temperature and as per MLR
 Enter the RFD (Ready For Dyeing) yarn in to the processing vessel.
 Add Chemical [Code-1]. Circulate for 3 minutes (In -> Out) and hold for 10 minutes.
Drain.
 Check pH. It should be 6 - 7. Check for channeling.
 Fill cold water, add chemicals [Code-2], Circulate for 5 minutes (In -> Out) and hold for
10 minutes.
 Raise temperature to 40°C and hold for 5 minutes.
 Add dissolved dyestuff [Code-3] in 2 to 3 portions with Out -> In circulation at 40°C.
 Raise temperature to 60°C @ 1.5°C/minute and hold for 15 minutes.
 Add Chemicals [Code-4] in two parts with In->Out circulation and run for 45 minutes.
 Check the sample and drain the dye bath.
 Rinse at room temperature for 5 minutes and drain.
 Give overflow rinse as per the dept of shade - 3 to 5 minutes.
 Fill fresh water, add chemicals [Code-5] and hold for 5 minutes. Drain.
 Fill hot water (60°C), add chemicals [Code-6] and circulate for 3 minutes.
 Raise the temperature to 95°C and run for 15 minutes. Drain.
 Rinse at 70°C for 10 minutes followed by 5 minutes overflow wash. Drain.
 Fill fresh cold water, add chemicals [Code-7] & [Code-8] and circulate for 3 minutes,
hold for 15 minutes and then drain.
 Fill Cold water, add chemicals [Code-9], circulate for 3 minutes and hold for 10 minutes.
Drain.
 Unload the batch.
Notes on Dyeing:
 For Shades above 7%, two soaping operations are necessary.
 Dye fixing is optional but not a substitute for thorough washing.
 Pressure difference during In->Out and Out ->In operations has to maintain a constant.
Package Dyeing Of Unmercerised Cotton Yarn With High Exhaust Reactive Dyes

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· Start Dyeing @50°C; ensure the starting bath pH be 6; adjust with Acetic Acid if necessary.
· Add salt (vacuum or Glauber’s salt) and hold for 15 minutes.
· Add ½ the volume of dissolved and filtered dyestuff and hold 10 minutes.
· Add ½ the volume of dissolved and filtered dyestuff and hold 10 minutes.
· Raise the temperature @2°C/minute to 80°C and hold for 20 minutes.
· Add ½ alkali (Soda ash) and hold 25 minutes.
· Add ½ alkali (Soda ash) and hold for 30 minutes.
· Check sample.
· Drain.
· Cold wash (10 + 10 minutes).
· Neutralize @ 40°C with adequate qty of Acetic acid.
· Cold wash – 10 minutes.
· Hot Wash @ 70°C (2°C/minute) – 10 minutes.
· Soap @ 95°C – 15 minutes (1st
soap).
· Soap @ 95°C – 15 minutes (2nd
soap)
· Soap @ 95°C – 15 minutes (3rd
soap)
· Hot Wash
· Sample check for shade and wash fastness
· Cold wash (10 + 10) minutes
· Acid wash with 1 gpl of acetic acid
· In the same acid bath – cationic softener treatment – 20 minutes
· Check pH – 6
· Unload.
Lycra Yarn – Pretreatment in Package dyeing machine:
Machine Circulation Cycle Settings:
Cheese winding: on plastic cones or cheeses.
Cheese Weight: Not more than 500 grams/cheese
 DEMINERALIZATION:
o Recipe:
 Kierlon Jet B Conc = 0.05%
 Lufibrol MFD = 0.05%
 @ 50°C for 2 cycles
 This is done to remove the unwanted mineral contents from the
fiber.
 Hot Wash = 1 cycle @ 50°C
 Cold Wash = 1 cycle

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 BLEACHING:
o Recipe:
 Soda Ash = 2.0%
 Stabilizer = 0.5%
 Lissopol D paste = 0.5%
 Hydrogen Peroxide(50%) = 2.0%
 @ 65° to 70°C for 45 to 60 minutes.
 Set the bath with chemicals other than H2O2.
 Raise temperature @ 1.5°C/minute
 Hot Wash = 1 cycle @ 50°C
 Peroxide Killer Treatment:
o Recipe:
 Organic Peroxide killer = 0.25%
 Acetic acid = 1.5 g/l
 @ 50°C for 1 cycle
 Drain, Cold wash
 Start Dyeing.
Note:
1. Bleaching temperature should not go beyond 65 to 70°C
2. Cheese weight = 500 grams and less is safer.
3. If you want to use regular cheese weights of 800 to 1000 grams, then the cheeses have to be
conditioned in the autoclave with moist steam at 100°C for 30 minutes, repeatedly, so that a
stable shrinkage percentage of yarn is reached. The linear shrinkage % should be 20 to 25%.
Sample dyeing process for cotton Recipe for cotton fabric
Recipe for Machine Wash Pretreatment
Wetting agent (NOF) – 0.5g/L
Sequestering agent (2146 – 1g/L
Anticreasing agent (JN) – 1g/L
Stabilizer (SIFA) – 0.7g/L
Caustic – 2g/L
H2O2 – 4g/L
Detergent (Sol ax) - 0.5 gm/L
Caustic -1 gm/L
Hydrous - 2 gm/L
Neutralization
Acetic Acid – 0.5g/L
Fabric weight Enzyme treatment
Enzyme UL – 1g/L
Fabric cold wash Dyeing
A/Acid – 0.5g/L
Leveling agent – 1g/L
Ant creasing agent – 1g/L
Dyes – X %
Salt – X g/l [salt & soda depend on liquor ratio

16
but general formula is 6:1 salt: soda, if used
power soda then 3:1]
Soda – X g/L
Recipe calculation After Treatment
Fixing agent (Neofix ECO/CIBA fix FRD) -
0.5 g/l
Soaping agent(Lipotol PS-60) - 0.8 g/l
Acetic acid - 1 g/l
Dye + Salt + Water and other chemicals Softening
Acetic acid - 0.2 g/l
Softener (Perrostol CWS) - 1 g/l.
Are taken by pipette in the pot, Then wash
fabric keep in the pot
Set. Time and temp. (60-80˚c x 60)
Fabric unload
Cold wash 2 times
Hot wash with Rsk
Dyer
Shade matching.
Sequence of cotton fabric dyeing Sequence of white fabric dyeing for cotton
Fabric loading
Required amount of water was taken (1:10)
Required amount of water was taken into the
M/C
Scouring
[NOF-0.5g/l, 2146-0.5g/l, JN-0.5g/l,
SIFA0.7g/l, NaOH: 3-4g/l, H2O2 4-8g/l 110°c
x 60 ́].
Fabric loading
Hot wash [NOF, Soda 90°c x 20, 1:10]
Acid wash /chemical remove
[A/Acid-0.5g/l, H2O2-0.5g/l, 60°c x 10 ́].
Scouring [NOF, 2146, JN, SIFA, H2O2 110°c
x 60 ́]
Enzyme
[Enzyme: 0.5g/l; UL/Biosoft 2xl. 50°c x 60 ́
PH 4.5].
Wash
Leveling
[LRDS-0.5-1g/l, JN -0.5g/l10 ́ PH 6.5-7].
Acid wash /chemical remove [A/Acid 60°c x
10 ́]
Salt (Glaubar salt– 60g/l) Enzyme [Enzyme UL 50°c x 45 ́ PH-4.5]
Color [60°-90°c x 60 ́] A/Acid [PH - 6 - 6.5]
Soda (power soda – 15g/l) Syno white 4BK [60°-80°c x 20 ́]
RSK hot [60°c x 60 ́] Washing
A/Acid (neutralization) A/Acid
Fixing [Dyaploe-Dco 30°c x 10 ́ PH 5.5] Softener [Hcs]
Softener [HCS 40°c x 20 ́] Washing
Unload the dyed fabric

17
Calculation for Lab Deep:
Recipe Calculation Formula:
Dye = (Shade % * Weight of the fabric in gm) / Stock solution %.
Or,
Required solution = WP / C
Where,
W = weight of fabric, yarn, or fiber
P = shade percentage
C = concentration of stock solution
CC = cubic centimeter.
For auxiliaries (chemicals) the formula is as below:
Required amount of solution (mls) = (g/l required * wt of substrate * LR) / (10 * concentration
(%) of stock soln)
For addition of auxiliaries in solids form such as salt the formula is:
Salt in g/l = (Required amount (%) * Sample weight * LR) / 1000
Conversion formula from percentage to g/l is as below:
g/l = required amount (%) * 10.
Calculation of Dyeing Recipe
If alkali conc. Is given in be. Then the formula to calculate this in g/l is as follows:
(%) of stock soln)
Or,
= (Required amount (%)* wt of substrate * LR) / (Concentration (%) of stock soln)
Or,
Required alkali soln in c.c. = ( g/l required * wt of substrate * LR) / (10* conversion value from
Be. to g/l of alkali )
Or,
Required alkali soln in c.c. = (Required amount (%) * wt of substrate * LR) / conversion value
from Be. to g/l of alkali
Example: Suppose a lab deep of a fabric sample (1*1 ribs) has to be formed with following
dyes & chemicals:
Dyes:
1. Rema Blue RR = 1.122%
2. React Red KHW = 2.014%
3. React Yellow KHW = 1.486%
Salt = 70%
Soda Ash (conc.20%) = 5 g/l
Caustic Soda (38 Be) = 1.32%
L: R = 1:8
Sample Wt. = 5 gm

18
% Stock Soln = 1
Therefore, recipe calculation for dyes and auxiliaries in g/l will be as follows:
For dyes:
We know,
Dye = (Shade % * Weight of the fabric in gm)/ (Stock solution %)
For,
1. Rema Blue RR = (1.122*5)/1=5.61 g/l
2. React Red KHW = (2.014*5)/1= 10.07 g/l
3. React Yellow KHW = (1.486*5)/1= 7.43 g/l.
For auxiliaries:
We know,
Salt in g/l = (Required amount (%) * Sample weight * LR) / 1000
Required Salt = (70*5*8)/1000 = 2.8 gm.
For Soda ash (conc.20%):
We know,
(%) of stock soln)
Required amount of soda ash in C.C. = (5*5*8)/(10*20) = 1.0
For Caustic soda (38 Be.):
We know,
Required alkali soln in c.c. = (Required amount (%) * wt of substrate * LR) /conversion value
from Be. to g/l of alkali
Required caustic soda = (1.32*5*8)/441 = 0.12 c.c.
[Since 38 °Be.NaOH= 441 gm NaOH 100% per 1lit NaOH soln]
Extra Water required:
= M:L – (required water to make soln of dyes & auxiliaries) = (5*8) – [(5.61+10.07+7.43) +
(1.0+0.12) ]
= 40 – 24.112
= 15.77 (Salt is added in solid form)
Equipments of Recipe Section:
Microprocessor pH Meter (Hanna Instrument)
Digital pipette
Digital Weighting Meter with Glass Box (Explorer, USA)
There are different matching systems followed in Labs. They are:
Tube light matching.
Sun light matching.
Ultra Violet matching.
Sodium light matching (show room).

19
Process Sequence of Lab Dip:
Lab dip plays an important role in dyeing process. Bulk dyeing process completely depends on
the lab dip development work. Lab dip is completely managed as the following sequence.
Lab Dip Requisition from buyer
↓
Entry in the computer
↓
First recipe is given by swatch/pantone number
↓
First correction
↓
Second correction
↓
Grading of sample (A, B, C, D)
↓
Yarn and knit sample send to buyer
↓
Approved by buyer
↓
Order for bulk production
↓
Production card with approved sample and recipe send to production section.
Process Flow Chart/Sequence of Dyeing Lab
At first dyeing is performed in dyeing laboratory and then starting for bulk production. A lots of
work is done in the dyeing laboratory. In the dyeing lab, lab dip or sample is developed by the
dyeing master. Lab dip plays an important role in shade matching & this is an important task
before bulk production.
Process Sequence of Dyeing Lab:
Sample/Swatch/Panton no. / TCX no. / TPX no. from the buyer
↓
Determination of sample’s possible color combination by the help of Spectrophotometer or
manual
↓
Dispersion by autodoser
↓
Trial dyeing of first recipe
↓
Unload
↓
Normal wash
↓
Hot wash with detergent

20
↓
Oven drying
↓
Ironing
↓
Shade matching in light box ( If Ok then send to buyer for approval)
↓
If not ok
↓
First correction takes from Spectrophotometer or manually
↓
Dispersion by autodoser
↓
↓
Unload
↓
Normal wash
↓
↓
Oven drying
↓
Ironing
↓
Shade matching in light box ( If Ok then send to buyer for approval)
↓
If not ok
↓
Second correction takes from Spectrophotometer or manually
↓
Dispersion by auto doser
↓
↓
Unload
↓
Normal wash
↓
↓
Oven drying
↓
Ironing
↓
Shade matching in light box

21
↓
If ok
↓
Send for buyer’s approval
↓
Bulk production by considering the buyer’s approved sample as standard
Note: This procedure is applicable for yarn or fabric dyeing.
Reactive Dyes - Shade Card 1
Reactive Dyes are used for all cellulosic Fibres, Silk & Viscose Rayon. These colours react with
cellulose in presence of alkali and also form chemical linkage resulting excellent fastness.
Reactive HE' Dyes are reactive dyes containing Bismonochlorotriazinyl group as reactive redical
and high fixation on dyeing fabric blends or, Terycot.These colours are suitable for exhaust
dyeing (801C) of medium and heavy depths.
Salt and Alkali Requirements:
Depth of Shade Salt gm per lit Soda Ash gm per
(O.W.F.) (Na2 .SO4) (Na2CO3)
0 - 0.5% 30 10
0.5 - 1.0% 45 15
1 - 2% 60 15
2 - 4% 70 20
Above 4% 90 20
Dyeing at 800C for 1 hour of the final alkali addition.
Reactive VS' Dyes are reactive dyes containing Vinyl Sulfone groups as reactive radical Suitable
for exhaust dyeing (60°C) , continuous dyeing and printing.
Dyeing at 60°C
Material to Liquor Ratio 1:2 to 1:3 1:4 to 1:6
Glauber's Salt gms/lit 50 50
30% NaOH Soln. ml/lit 3-6 2-3
Soda Ash gms/lit 5 5
Trisodium Phosphate gms/lit 30 20-25
Dyeing at 600
C for 60 minutes final alkali addition.
After-treatment
Rinse in cold water, Hot rinse, soap at boil with 2 gm/l neutral detergent for 15 minutes, Hot
rinse, Cold rinse & Dry.

22
NOTES:
 For T. Blue G. dyeing use 50 gms/lit Glauber's Salt for exhaustion and 15 to 20 gms/lit
Soda Ash alongwith 3-5 gms/ lit NaOH (72°Tw) in last twc ends at 800C 'or fixation
 For Reactive Yellow FG, Red C2G & Red 5B, 80 gms/lit Glaubers Salt gives better
colour yield
 In case or Reactive Brill. Blue R only 1 quarter of required Salt is added over first and
second turn. The remaining Salt is added only after the addition of Alkali.
REACTIVE DYES-TANACTIVE HE BRAND DYES
DYEING PROCEDURE-DYEING METHODS -
Winch, jet, package & beam dyeing machines.
These dyes are specially designed for exhaust dyeing methods. The dyeing method selection
depends upon the type of substrate to be dyed and the machinery to be used for dyeing.
Depth of Shade Salt
Unmercerised
cotton(gm/l)
Mercerized cotton or
Viscose Rayon
Soda Ash
(gms/l)
Fixation time
(min.)
Upto 0.10% 10 5 10 30
0.11-0.30% 20 10 10 30
0.31-0.50% 30 20 10 45
0.51-1.00% 45 30 15 45
1.01-2.00% 60 40 15 45
2.01-4.00% 70 55 20 60
Above 4.00% 90 65 20 60
Method No. 1: Salt addition in portions (suitable for mercerized yarn)
This process is recommended for non-circulating liquor machinery and it is suitable for all
depths of shade.

23
Method No. 2: Salt addition at start (Suitable for unmercerised yarn)
This method is recommended for machines with liquor circulation and it is suitable for medium
to heavy depth of shades.
Method No. 3: Both salt & alkali addition at start
The method is recommended for machines with liquor circulation, primarily for the dyeing of
medium - heavy binary combinations. It is suitable for unmercerised cotton.
Note 1: A mixture of soda ash and caustic soda is recommended alkali for this method.
Depth of Shade Soda ash gms/l Caustic Soda 100% gms/l
Upto 1.0% 5 0.2
1.01 to above 5 0.5
Method No. 4: (Dyeing Pale Shade) (Garment dyeing)
The method is recommended for machines with microprocessor controlled addition system for
dyeing pale shades (less than 0.5% depth) and for all shades on mercerized cotton & viscose
packages

24
Method No. 5: Isothermal Method (Dyeing heavy shades garment)
The method is recommended for machines with microprocessor controlled addition systems for
medium to heavy depths (>than 0.5% depth) on unmercerised cotton.
Dyeing method for Jigger machines-
Due to high temperature dyeing the problems of off-shade selvedges of too pale selvedges are
often encountered in dyeing with these machines. The following precautions hence should be
taken to avoid such problems.
1. To use closed type jiggers so that a uniform temperature is possible across the width of
fabric.
2. Batch the fabric evenly.
3. Maintain the dye bath at minimum of 85-90o
C during salt stage.
4. Adjust the dye bath temperature 85-90o
C to ensure that fabric is maintained at minimum
80o
C during alkali addition stage.
Procedure -
Set the dye bath at 90o
C with resist salt 2 gms/l. Now add 1/2 amt. of dye and run one end. Then
add remaining 1/2 amt. & run another one end. Add 1/2 amt. of salt & run one end. Add
remaining 1/2 amt. Of salt and run another end. Maintain 80o
C temperature continue to run for 2
ends. Now add 1/2 amt. of soda ash & run for one end. Then add remaining 1/2 amt. Soda ash &
run for another one end. Then add remaining 1/2 amt. soda ash & run for another one end. Then
run for 4 ends or more if required & wash. (1 end =10 minutes)
Dyeing method for cotton / polyester blend-
The one bath two stage dyeing method for polyester / cotton blend is applicable on jet, beam or
package dyeing machines.
2 gm/l Buffer pH 5 (5.5) X% GAAYACTIVE 'HE' dye
1 gm/l Anionic dispersant 50 gms/l Salt
X% Disperse Dye 15 gms/l T.S.P. Soda ash

25
Salt and alkali requirements-
Depth of Shade % on total weight of goods Salt (gms/l) Soda Ash (gms/l)
Upto 0.2% 15 10
0.21-0.4% 20 15
0.41-0.80% 30 15
0.81-1.6% 50 20
Aabove 1.6% 70 20
Washing - off procedure-
In order to obtain maximum wet-fastness properties, brightness and purity of shades with
consistent dyeing results, it is essential to give a through 'Soaping' to clear-off unreached
hydrolyzed dye form the dyed fabric.
The dyed fabric is rinsed repeatedly in cold water to remove most of the alkali, salt and unfixed
dye present and rinse again in warm water not higher than 60o
C. then run in a bath containing:
Anionic detergent - 1-2 gms/liter for 15 minutes at the boil. Then rinse in warm water (up to
60o
C) and finally in cold water. The most satisfactory results in washing-off, particularly for
piece goods, are obtained by employing an Open soaper or perforated beam-washing machine. If
such equipments are not available, conventional ones like jig or winch may be used. For yarn in
the hank form open-vat is employed and for yarn in packaged form the package-dyeing machine
itself used.
About Blend Dyeing:
Blends are any textile material from fibre through yarn to fabric which are deliberate
combinations of chemically or physically different fibrous polymer.cotton and Polyester blend is
an example of chemically different blend and Cotton and Viscose is physically different blend
because both are cellulosic.
Object of Blending:
1. Dilution of an expensive, lusterious fibre by blending with cheaper substitute.
2. To incorporate of more durable component to extendthe useful life.e.g. Core spun yarn.
3. A compromise to take advantage of disirable performance characteristics, contribute by
both fibre component.e.g. P/C blends to get comfort of cotton, strength and crease
recovery of polyester.
4. The development of novel fabric design for garments incorporating multicolour
effect.e.g. Polyester part is dyed and cotton part undyed.

26
5. The presence of attractive appearance using byy combination of yarn of different luster,
crimp is possible by blending.
6. Colourant modification is possible by blending.
7. Finishing process modification.
8. Improved moisture absorption.
9. Reduce anstistatic characteristics pilling.
Process Sequence of P/C Blend Dyeing:
Desizing
↓
Scouring
↓
Drying
↓
Heat setting
↓
Mercerization
↓
Drying
↓
PET dye
↓
Reduction clearing
↓
Drying
↓
Singing
↓
Cotton dye
↓
Washing
↓
Soaping
↓
Washing
↓
Drying

27
Dyeing P/C Blend with Disperse and Vat Dye:
Recipe:
Disperse dye ----------------------------------------X%
Vat dye-------------------------------------------------Y%
Dispersing agent------------------------------------o.5-1%
Wetting agent-----------------------------------------0.5-1%
PH-------------------------------------------------4-5 with acetic acid(30%)
Procedure:
Prepar the bath with dispersing agent,wetting agent and acetic acid.Treatment for 10-15 minute
at 50-60 degree C.Then add disperse and vat dye in the bath.Dyeing for 10-15 minute.Raise
temp. up to 130 degree C in 60-90 minute.After PET part dyeing cool to 80 degree for proper
levelling then add caustic and hydrose and dyeing 15 minute.Cooling to 60 degree c and dyeing
for 30 minute for better exhaustion.Rinse with cold water and oxidation with hydrogen per oxide
for 15 minute at 50 degree C.Then rinseing with cold water and soaping 95 degree c for 25
minute using 2g/l lissapol.Hot and cold rinse and then final wash off.
Dyeing P/C blend with Disperse and Reactive Dye (Thermosol Process):
Recipe:
Disperse dye -----------------------------------X%
Reactive dye ----------------------------------Y%
Soda ash-----------------------------------------5-20g/l
Migration inhibitor ----------------------------10-20g/l
Wetting agent----------------------------------1-2g/l
Dyeing Procedure:
Padding:
Padding with disperse and reactive dye at 20-30 degree C. Liquor pick up 60-80%.
Predrying:
Partial drying is done to avoid migration of dyes.Here keep m.c 25%.
Drying:
Complete and even dyeing at 110-150 degree C.
Thermofixation:
It's done at 180-220 degree C about 30-45 sec. to fixation dye.Polyester dyeing complete here
Alkali Padding:
Padding at 20-30 degree C.Pick up 50-60%.Caustic and salt used for Procion mx and Procion H.
Steaming:
Steaming is done 103-105 degree C about 30 sec. for procion mx and 45-75 sec.for procion H.
Wash off:
A typical 8 box wash off is given by Cold,hot water and detergent.
Box-1:-------------------------------------water 60 degree C.
Box -2&3:-------------------------------------Detergent 5 gm/l at boil
Box-4&5:---------------------------------------water at the boil
Box-7;-------------------------------------------water 60 degree C.
Box-8:-------------------------------------------Cold water.

28
Classification of the methods for dyeing of P/C blend:
Exhaust dyeing method or batch dyeing method-
This is again classified in the following three groups-
1. Two bath dyeing
2. One bath one step dyeing
3. One bath two step dyeing method
Thermosol Dyeing method -
It is again classified in to two groups-
1. Continuous dyeing-
2. Pad batch process (semi-continuous)
Note-In continuous dyeing process may be single bath or double bath.
EXHAUST DYEING:
Two bath dyeing
1. This is the process in which we have to dyed first polyester part in the HTHP beam dyeing
machine or HTHP jet dyeing machine and the cotton part is dyed in the jigger machine.
2. Batch process
3. Machine used for dyeing of polyester part-
 HTHP Beam dyeing machine( First commercialized HTHP machine)
 HTHP jet dyeing machine
4. Machine used for dyeing of cotton part-
5. Jigger dyeing machine used

29
PROCESS ROUTE P/C BLEND DYEING:
MACHINE FOR POLYESTER DYEING:
HTHP beam dyeing machine-
No need to explain the whole process of dyeing in beam dyeing machine. Only some important
points we will discuss about it-
Advantages & features:
1. Loading and unloading of the fabric is easy and time of dyeing is short.
2. Dyeing in open width form.
3. Most suitable for those fabrics that might crease, extend or abrade when dyed in
machines where the fabric is in motion.
4. Not appropriate for compact fabrics
5. De-aeration is essential to avoid paler dyed spots.
6. A wetting agent helps to eliminate air bubbles within the fabric roll.
Recipe used HTHP dyeing:
 Disperse dye- X%(depends upon the shade)
 Dispersing agent-1g/l
 Sequestering agent-1-2g/l(If required)
 Defoamers -.5 to 1g/l
 Levelling agent-.5 to 1 g/l
 Wetting agent- .5g/l
 Acetic acid-enough to get ph=5-6

30
Flow of the liquor usually in the in-to-out direction, but it can be reversed. Out-to-in flow can
compress the material causing flattening and glazing, particularly on the inner layers.
 Material stationary and liquor is moving.
 Batching is very important; during batching tension should be uniform and optimum.
 M:Lratio is 1:10
 Both cloth and yarn can be dyed on this machine.
Major Chemicals Used in Textile Wet Processing
Introduction:
Chemical analysis always involves the use of different chemicals. In order to assure accurate
analysis results, the chemicals used need to be standardised, the procedures must be followed
exactly and the data obtained have to be analysed statistically. If an instrument is used, it should
be maintained and calibrated properly.
In a chemical analysis, especially involving quantitative analysis, the amount of chemical used is
critical and can be determined by the measurement of concentration if it is a solution, or by
weight, if it is a solid. Sometimes, the concentration of a solution can be easily determined by
using another known solution through titration. For acids and bases, if the concentration is
sufficiently low, the pH concept is generally used to represent the concentration of the acid or
base in the aqueous solution. For the analysis of common chemicals, such as caustic soda, acetic
acid, soda ash, sodium dithionite, hydrogen peroxide, and so on, titrimetric analysis and
gravimetric analysis are widely used. For the analysis of surfactants and other chemicals,
qualitative spot tests and specialised instruments should be utilized.
Before the analysis of chemicals in textile wet processing we should to know about
concentration, titration, weighing, pH etc. Now a short identity of these is given below.
Concentration:
The concentration of a solute is usually expressed as the amount of a solute in a unit volume of a
solution. The amount of a solute can be in grams (g), kilograms (kg), moles (mol), or normals
(n). The unit volume of a solution is always in litres (l).
Titration:
Titration is a method by which the concentration of an unknown solution can be determined
using a standardised solution with a known concentration through a stoichiometric reaction. The
end point of the chemical reaction is indicated by the colour change of an indicator or an
instrumental reading. The standard solution of a known reagent is the titrant and the unknown
solution is the titrand.
Weighing:
Weighing is an important operation in gravimetric analysis. Usually it involves the use of an

31
electronic balance with a minimum readability of 0.1 mg. In order to ensure reproducible results,
sample handling is very critical especially when hygroscopic materials are weighed.
pH:
pH is a scale between 0 and 14 used to express the concentration of hydronium (H3O+, or H+)
ions in a solution. It is defined by Equation.
pH = – log [H+]
Major Chemicals Used in Wet Processing:
Acids, bases, salts, surfactants, oxidising agents and reducing agents are the major chemicals
those are widely used in wet processing industry.
Acid:
An acid (from the Latin acidus/acēre meaning sour) is a substance which reacts with a base.
Commonly, acids can be identified as tasting sour, reacting with metals such as calcium, and
reacting with bases such as sodium carbonate. Aqueous acids have a pH under 7, with acidity
increasing the lower the pH. Chemicals or substances having the property of an acid are said to
be acidic.The following standard solutions are used in the acid analysis. They are usually
prepared in advance and consumed within a certain period of time.
1. H2SO4, 0.1 N, 0.25N, 0.5 N and 1 N;
2. HCl, 0.1N, 0.25 N, 0.5 N and 1 N;
3. HNO3, 0.1 N;
There are two types of acid
1. Inorganic acid
2. Organic acid
Inorganic Acid:
Inorganic acid are Sulphuric acid (H2SO4), Hydrochloric acid (HCl), Nitric acid (HNO3),
Phosphoric acid (H3PO4), etc.
Sulphuric Acid (H2SO4):
The concentration of sulphuric acid (H2SO4) can be determined by using Baume’s (ºBé)
hydrometer. The titration of sulphuric acid is carried out using sodium hydroxide in the presence
of phenolphthalein as an indicator. The end point is reached when a faint pink color is persistent.
HCl
The concentration of hydrochloric acid (HCl) can be determined using a hydrometer, in a very
similar manner to the determination of sulphuric acid concentration. Hydrochloric acid is a
volatile acid at high concentration.

32
HNO3
The concentration of nitric acid (HNO3) can be determined using a hydrometer. If titration is
used to determine the concentration, phenolphthalein is the indicator.
H3PO4
The concentration of phosphoric acid (H3PO4) can be determined in a similar manner to that
discussed for H2SO4, HCl and HNO3.
Organic Acids:
Organic acids are HCOOH (formic acid), Acetic acid etc.
HCOOH
HCOOH (formic acid) is the simplest organic acid in terms of its organic structure. Concentrated
HCOOH is usually 88% in strength. Since formic acid is a volatile acid, precautions should be
taken to prevent loss of strength in the sample preparation stage. The concentration of formic
acid can be determined by acid– base titration as well as by redox titration owing to the reduction
power of formic acid.
CH3COOH
Acetic acid is a weak acid. It is available at different concentrations. Highly concentrated acetic
acid at 98% and above is called glacial acetic acid because its freezing point range is between
13.3 ºC (98%) and 16.7 ºC (100%). Glacial acetic acid is flammable. The concentration of acetic
acid can easily be determined using acid–base titration with phenolphthalein as an indicator. The
water used should be free from CO2, prepared by boiling before use.
Base:
A base in chemistry is a substance that can accept hydrogen cations (protons) or more generally,
donate a pair of valence electrons. A soluble base is referred to as an alkali if it contains and
releases hydroxide ions (OH−) quantitatively.Bases are two types
1. Inorganic and
2. Organic bases
Inorganic Bases:
Inorganic bases are Sodium hydroxide (NaOH), Sodium carbonate (Na2CO3), Ammonium
hydroxide (NH4OH) etc.
NaOH
Sodium hydroxide (NaOH) is also called caustic soda. It is available in solution at different
concentrations or in solid form. Commercial NaOH often contains a little sodium carbonate
(Na2CO3) as a by-product of the manufacturing process. This small amount of Na2CO3 will
usually not influence its use in textile wet processes.

33
Owing to its strong alkalinity, NaOH can react with CO2 in air easily. It can also absorb water
very quickly.
Na2CO3
Sodium carbonate (Na2CO3) is also called soda ash. In textile wet processes, it is often available
in anhydrous form. Its purity can be > 99% Na2CO3 (58% Na2O).
If the concentration of a Na2CO3 solution needs to be determined, a titrimetric method identical
to the ones listed for NaOH in this section can be used. If the existence of bicarbonate is a
concern (very rarely in textile wet processes) the following method can be used to determine the
content of bicarbonate in sodium carbonate.
NH4OH
Ammonium hydroxide (NH4OH) is a water solution of ammonia gas (NH3). It can also be called
aqua ammonia or ammonia water. The concentration determination can be done using either a
hydrometer or an acid–base titration. Since ammonia is volatile, the concentration determination
should be done with care to avoid any loss of strength. If a hydrometer is used, the sample and
the hydrometer should be cooled to 5–10 ºC. Table 4.75 lists the relationship between the
concentration (% w/w) and ºBé of NH4OH at 10 ºC. Acid–base titration can also be used to
determine the concentration of NH4OH.
Organic Bases:
Organic bases are Triethanolamine, N (CH2CH2OH) 3, Ethylenediamine (H2NCH2)2 etc.
Triethanolamine
Triethanolamine, N (CH2CH2OH) 3, is a strong organic base miscible with water, methanol and
acetone. The pH of its 0.1N aqueous solution is 10.5. Analytical grade N(CH2CH2OH)3 is a
highly hygroscopic and viscous liquid with a pale yellow or no colour. Its melting point is
between 18 and 21 ºC. Its density is about 1.12.
Ethylenediamine
Ethylenediamine, (H2NCH2)2, is a strong organic base miscible with water and alcohol. It is a
colourless and viscous liquid with a density of 0.898 and a melting point of 8 ºC. The pH of a
25% aqueous solution is 11.5. Like triethanolamine, it is an aliphatic amine soluble in water and,
therefore, can be determined by the acid–base titration with methyl orange as an indicator.
Salts
Salts are the products of the acid-base neutralisation reaction. The salts used most in textile wet
processes are common salt (NaCl, sodium chloride) and Glauber’s salt (Na2SO4, sodium

34
sulphate). The content analysis of salts is usually conducted by using a precipitation titration
method which may be followed by filtering and weighing procedures to obtain the final results.
Sodium chloride
Industrial grade NaCl has a content of 92–98%. The precipitation titration can be conducted
using 0.1 N AgNO3 as the titrant and 5% K2CrO4 as the indicator (the Mohr method). The
sample chloride solution should be buffered with calcium carbonate to a pH between 6.3 and 7.2
in order to avoid any interference from other ions present in the solution.
Sodium sulphate
Na2SO4 is available in two types, anhydrate and decahydrate. Its content analysis can be
conducted based on the precipitation method using barium chloride (BaCl2).
An excess amount of barium chloride is added into the sample solution which has been filtered
beforehand to form BaSO4 precipitate as indicated by the following reaction:
Na2SO4 + BaCl2 →2NaCl + BaSO4↓
Surfactants
Surfactants are widely used in textile wet processes for the purpose of wetting, dispersing,
emulsifying and cleaning. The molecular structures of surfactants have a distinctive hydrophilic
moiety and a distinctive hydrophobic moiety. When they are used at a sufficient concentration,
the surface/interface tension of the solution is lowered and micelles are formed, which give the
solution extra properties.
According to their ionic properties in aqueous solution, traditional surfactants can be divided into
four categories: anionic, cationic, amphoteric and non-ionic.
Surfactants are four types
1. Anionic surfactants ,
2. Cationic surfactants,
3. Non-ionic surfactants and
4. Amphoteric surfactants
Amphoteric surfactants:
Amphoteric surfactants contain both anions and cations. They should show positive results when
tested using either the basic methylene blue test for anionic surfactants or the alternative
bromophenol blue test for cationic surfactants.
A saturated bromine aqueous solution can also be used to determine the type of amphoteric
surfactant. Add 5 ml of 1% sample solution to 1.5 ml saturated bromine aqueous solution.

35
Observe the colour of the precipitate. Heat the mixture and observe the change in the precipitate.
If the precipitate is a yellow to yellow-orange colour and is dissolved to form a yellow solution
after heating, the sample is an imidazoline or alanine type of amphoteric surfactant. If the
precipitate is a white to yellow colour and insoluble after heating, the sample is the other type
of amphoteric surfactant.
Oxidising agents and reducing agents
Oxidising agents are mainly used for bleaching and reducing agents are mainly used for vat
dyeing in textile wet processes. These agents are often strong chemicals and need to be handled
with care. The assay of these agents is almost always based on the redox titration. In a redox
reaction, an oxidising agent (oxidant) is reduced (it gains electrons) and a reducing agent
(reductant) isoxidised (it loses electrons). The redox reaction can be written as two half
reactions shown below:
Oxidation reaction: reducing agent → oxidized form + n e–
Reduction reaction: oxidising agent + n e– → reduced form
The net reaction is: reducing agent + oxidising agent → oxidised form + reduced form
Oxidising Agents:
Hydrogen peroxide
Hydrogen peroxide (H2O2) can be titrated with potassium permanganate (KMnO4) in an acid
medium. H2O2 is the reducing agent and KMnO4 is the oxidising agent.
Sodium Hypochlorite
In hypochlorite bleaching of textiles, active chlorine is the species measured for the control of
the bleaching process. Iodometry is the method used to determine the content of active chlorine.
Sodium perborate
Either sodium permanganate or potassium iodide can be used to titrate the sodium perborate
(NaBO3•4H2O). Dissolve 0.2 g of sample in 200 ml distilled water, add 40 ml 6 N H2SO4, and
titrate with 0.1 N sodium permanganate until a pink colour appears.
Reducing Agents:
Sodium hydrosulphite (Na2S2O4)
It is the Dilute of 10 ml 40% formaldehyde with 50 ml distilled water.
Glucose
Glucose (C6H12O6) can be used as a reducing agent in vat and sulphur dye applications. It can

36
be analysed by iodometry. Accurately prepare a 0.5% glucose solution.
Sodium thiosulphate
Sodium thiosulphate (Na2S2O3•5H2O) can be titrated easily by iodometry. Accurately weigh a
5 g sample and dissolve it in 500 ml distilled water to make a 1% sample solution.
Miscellaneous Chemicals
Ethanol
The specific gravity of ethanol (C2H5OH) is directly related to its content. Table 4.7 lists the
relationship between the volume% (weight %) and the specific gravity of ethanol at 15 ºC.
Ethylene glycol and glycerol
ASTM method D161518 may be used to estimate the concentration of ethylene glycol and
glycerol in an aqueous medium.
Others
Urea
Urea is tested for the content of nitrogen using H2SO4 and formaldehyde. The indicator used is a
mixed indicator containing 0.5 g phenolphthalein and 0.5 g thymol phthalein dissolved in 100 ml
ethanol. A 25% formaldehyde solution used should be neutralised before use. The procedures of
the method are briefly described below.
1. Dissolve 1 g fully dried sample in a small amount of water; add 3 ml concentrated
H2SO4; mix well and heat on a hot plate.
2. Heat until the release of CO2 (bubbling) has stopped and dense white smoke (SO3) is
emitted; leave to cool down.
3. Add 50 ml distilled water and 2 drops of methyl red indicator.
4. Neutralise the acidity of the solution with 6 N NaOH added dropwise until the red colour
changes to a pink colour; add 0.5 N NaOH slowly to change the solution colour to a faint
pink.
5. Add 40 ml 25% neutralised formaldehyde solution and 5 drops of the mixed indicator;
stand for a few minutes.
Fluorescent whitening agents
Fluorescent whitening agents (FWA) are a special type of chemical that can significantly
increase the apparent whiteness of treated fabrics. They absorb UV radiation and re-emit the
absorbed energy in the blue visible light range which makes the treated fabrics appear whiter.
The easiest test for the effect of FWAs is simply a visual examination of the whiteness of treated
fabrics. Manufacturer’s recommendations should be followed in order to achieve the best
whitening effect.
Ethylenediamine tetraacetate (EDTA)
Ethylenediamine tetraacetate (EDTA) can form a few different water soluble salts with calcium,
potassium and sodium, for example, calcium disodium, trisodium and tetrasodium salts. EDTA
tetrasodium salt is used most widely in many industrial applications as a powerful chelating

37
agent. Its 1% solution has a pH of 11.3. It can chelate with many divalent and trivalent metal
ions to form watersoluble metal complexes.
HTHP BEAM DYEING MACHINE:
Sectional diagram of a high-temperature beam dyeing machine
Disadvantages of beam dyeing machine:
 —Fabric of different width can not be dyed together on a single beam.
 —The dyed fabric may be display moiré effect if it is tightly due to shrinkage.
 —Uneven dyeing may occur if the beam is fully loaded, as the dye liquor has penetrate
several layers of fabric.
JET DYEING MACHINE:

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HTHP jet dyeing machine:
The jet dyeing machine is an extension of the HPHT winch dyeing machine. Jet dyeing machine
developed by BURLINGTON Industries and first machine developed in 1963 by Gaston country
Machine co. of U.S.A
Features:
 Both material and liquor is moving.
 Dyeing in rope form.
 Fabric speed usually 200-250mt/min
 The jet dyeing can usually operated up to 1400c under high pressure and having capacity
capable of dyeing 100 to 150 kg of fabric at a time
Chemicals added
 Acids
 Buffers
 Sequestering agent
 Anticrease agent
 Defoamers
 Levelling agent
DEVELOPMENT IN JET DYEING MACHINE:
 Soft flow jet- slow motion of fabric. Suitable for knitted fabric
 Super jet dyeing machine- M:L is 1:1
 Aerodynamic jet dyeing machine
 Jet created by mixture of air + water
 M:L is 1:1 , drain out at a 130c
 Multi-nozzle sot flow jet dyeing machine
Advantages of jet dyeing machine:
1. Fabric of two different width can be dyed at a time so that two lots can be combined
together for dyeing.
2. No special batching device is required for winding the fabric as in beam dyeing.
3. There is no flattening effect or uneven dyeing on the fabric as in beam dyeing

39
Disadvantages:
1. There is possibility of entanglement of light-weight fabric during dyeing.
2. Loose fibres removed from the fabric may get redeposited on the fabric surface as well as
on the interior of the jet dyeing vessel, this problem does not arise in beam dyeing.
3. Yarn can not be dyed in a jet dyeing machine whereas it can be dyed in a beam dyeing
machine.
PROBLEMS-
1. Foaming problem
2. Oligomers problem
3. Rope marks
Machine used for cotton dyeing:
Jigger dyeing machine
 Open jigger or closed jigger dyeing machine-
 Closed jigger specially for vat dyeing.
 Liquor is stationary and fabric is moving.
 500 t0 1000 meter of fabric is processed in one time.
 M:L ratio in jigger dyeing machine is about 1:5.
 Usually take 10 min. for each passage
One bath two step dyeing-
One-bath dyeing processes, using both the dyes such as following in the same dye bath.
1. Disperse and vat dyes.
2. Disperse and reactive dyes.
3. Disperse and direct dyes.
Dyeing machine:
Name of the m/c: Dyeing machine
Brand Name: Dilmenlar
Manufacturing Company: Turkey
Year of Manufacturing: 2004
Machine capacity: 150 kg
No. of nozzle: 02
Maximum Temperature: 135°c
Motor: 01
Winch Motor: 01
Pump Motor: 01
Jigger dyeing machine is the most commonly used for dyeing all kinds of cotton fabric. There
are mainly two types of jigger dyeing machine. One is open jigger dyeing machine and other is
closed jigger dyeing machine.
The open jigger dyeing machine is shown in the figure. This machine consists of V shaped
stainless steel vessel. Two rollers are fitted above the vessel called as cloth rollers. These rollers
are rotated by power. Out of these two rollers one roller is driven by a motor which is called take

40
up roller and the other roller from which the cloth is delivered is called let off roller. When all
the cloth is passed from the let off roller to the take up roller, it is called as one end or one turn.
The number of ends or turns depends upon the type of the fabric and also the percentage of the
shade.
Initially, a large length of (50 kg) cloth is wound on the let off roller and take up roller is then
driven by the power. After one end is taken, the take up becomes let off roller. These backward
and forward movements of cloth through the dye liquor absorb more and more dye.
The capacity of the jigger is 100 to 150 gallons. In the modern jigger, automatic devices are
fitted along with the timing switch by using reversing will take place automatically.
When dyeing all the dye liquor should not be added at one time. The dye liquor should be added
in batch wise, in order to get even shade on the cloth. In the present scenario, closed types of
jiggers are used. The main advantage is to prevent heat loss and chemical loses by evaporation.
This type of jigger is very important for dyeing vat, Sulphur etc.
Advantages of Jigger Dyeing Machine
1. The cloth can be dyed in open width form of full width form.
2. Chemical and heat loses are less when compared to winch dyeing machine
3. The material to liquor ratio is 1:3 (or) 1:4 which saves considerable amount of chemical cost
and steam cost.
Disadvantages of Jigger Dyeing Machine
It exerts lot of tension in the warp direction and because of this normally woolen, knitted fabric,
silk etc are not dyed in jigger dyeing machine.
Modern Machinery Used in Dyeing Process:
Modern dyeing machines are made from stainless steels. Steels containing up to 4%
molybdenum are favored to withstand the acid conditions that are common. A dyeing machine
consists essentially of a vessel to contain the dye liquor, provided with equipment for heating,
cooling and circulating the liquor into and around the goods to be dyed or moving the goods
through the dye liquor. The kind of machine employed depends on the nature of the goods to be
dyed. Labor and energy costs are high in relation to total dyeing costs: the dyers aim is to shorten
dyeing times to save steam and electrical power and to avoid spoilage of goods.
Modern dyeing machine

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The conical-pan loose-stock machine is a widely used machine. Fibers are held in an inner
truncated conical vessel while the hot dye liquor is mechanically pumped through. The fiber
mass tends to become compressed in the upper narrow half of the cone, assisting efficient
circulation. Leveling problems are less important as uniformity may be achieved by blending the
dyed fibers prior to spinning.
The Hussong machine is the traditional apparatus. It has a long, square-ended tank as a dye bath
into which a framework of poles carrying hanks can be lowered. The dye liquor is circulated by
an impeller and moves through a perforated false bottom that also houses the open steam pipe for
heating. In modern machines, circulation is improved at the points of contact between hank and
pole. This leads to better leveling and elimination of irregularities caused by uneven cooling. In
package-dyeing machines dye color may be pumped in rather two directions:
1. Through the perforated central spindle and outward through the package or
2. By the reverse path into the outer layers of the package and out of the spindle. In either
case levelness is important.
Some package-dyeing machines are capable of working under pressure at temperatures up to
130C.
The winch is the oldest piece of dyeing machine and takes its name from the slated roller that
moves an endless rope of cloth or endless belt of cloth at full width through the dye liquor.
Pressurized-winch machines have been developed in the U.S.
In an entirely new concept; the Gaston County jet machine circulates fabric in rope form through
a pipe by means of a high-pressure jet of dye color. The jet machine is increasingly important in
high-temperature dyeing of synthetic fibers, especially polyester fabrics. Another machine is the
jig. It has a V-shaped trough holding the dye color and guide rollers to carry the cloth at full
width between two external, powered rollers, the cloth is wound onto each roller alternately, that
is, the cloth is first moved forward, then backward through the dye color until dyeing is
complete. Modern machines, automatically controlled and programmed, can be built to work
under pressure.
It was found that in using Winch machines, there were some inherent problems. So the Jet
dyeing machines when they came up in the 1970’s were specifically designed to overcome those
shortcomings.
In the Jet dyeing machine the reel is completely eliminated. A closed tubular system exists where
the fabric is placed. For transporting the fabric through the tube a jet of dye liquor is supplied
through a venturi. The Jet creates turbulence. This helps in dye penetration along with preventing
the fabric from touching the walls of the tube. As the fabric is often exposed to comparatively
higher concentrations of liquor within the transport tube, so little dye bath is needed in the
bottom of the vessel. This is just enough for the smooth movement from rear to front. Aqueous
jet dyeing machines generally employs a driven winch reel along with a jet nozzle.
The following diagram explains the functioning of a Jet dyeing machine:

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Types of Jet Dyeing Machine:
In deciding the type of dyeing machine the following features are generally taken into
consideration for differentiating. They are the following. Shape of the area where the fabric is
stored i.e. long shaped machine or J-box compact machine. Type of the nozzle along with its
specific positioning i.e. above or below the bath level. Depending more or less in these criteria
for differentiation following types of Jet Machines can be said to be as developments of the
conventional jet dyeing machine.
1. Overflow Dyeing Machine
2. Soft-flow Dyeing Machine
3. Airflow Dyeing Machine
Advantages of Jet Dyeing Machine:
The Jet Dyeing Machine offers the following striking advantages that make them suitable for
fabrics like polyesters.
1. Low consumption of water
2. Short dyeing time
3. Can be easily operated at high temperatures and pressure
4. Comparatively low liquor ratios, typically ranges between 1:4 and 1:20
5. Fabrics are handled carefully and gently
Soft Flow Dyeing Machine:
In the soft flow dyeing machine water is used for keeping the fabric in circulation. The
conceptional difference of this equipment from a conventional jets that operates with a hydraulic
system is that the fabric rope is kept circulating during the whole processing cycle (right from
loading to unloading). There is no stopping of liquor or fabric circulation for usual drain and fill
steps. The principle working behind the technique is very unique. There is a system for fresh
water to enter the vessel via a heat exchanger to a special interchange zone. At the same time the
contaminated liquor is allowed channel out through a drain without any sort of contact with the
fabric or for that matter the new bath in the machine.
Key Features of Soft flow Dyeing Machine:
 Significant savings in processing time.
 Savings in water that is around 50%.
 Excellent separation of different streams results in optimum heat recovery and a distinct
possibility of further use or a dedicated treatment.

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Principle of Soft Flow Dyeing Machine:
Textile material can be dyed using batch, continuous or semi continuous process.
Batch processes are the most common method used to dye textile materials. There are three
general types of batch dyeing machines:
1. In which fabric is circulated
2. In which dye bath is circulated
3. In which both the bath and material is circulated.
Jet dyeing machine is the best example of a machine that circulated both the fabric and the
dyebath. Jet dyeing is used for knitted fabrics. For Terry-towels soft flow dyeing is use.
In jet dyeing machine the fabric is transported by a high speed jet of dye liquid.
As seen in the figure, this pressure is created by venturi. A powerful pump circulates the dyed
bath through a heat exchanger and the cloth chamber. Cloth guide tube helps in circulation of
fabric.
Types of Soft Flow Dyeing Machine:
A few of the commercially popular brands along with their particular technical specifications are
discussed here. The categories are not exhaustive as such.
Multi Nozzle Soft Flow Dyeing Machine:
Technical Features:
1. Very low Liquor ratio - around 1:1 (Wet Fabric)
2. Can reach high temp. up to 140°C
3. Easily dye 30 to 450 g/mt.sq. of fabrics (woven & knitted fabrics)
4. Number of very soft-flow nozzles
5. No pilling effect
6. Wide capacity

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Multi Nozzle Soft flow Dyeing Machine
High Temperature High Pressure Soft Flow Dyeing Machine:
Technical Features:
1. Compact body made of stainless steel.
2. High efficiency heat exchanger for quick heating/cooling.
3. Compact body made of stainless steel.
4. Heating rate - around 4°C/Min upto 900°C - around 3°C/Min upto 135°C At steam
pressure of 6 Bar.
5. Cooling Rate- around 4°C/ Min At water pressure of 4 Bar and 15°C.
6. Maximum working temp is 135°C.
7. Maximum working pressure of 3.2 Bar.
8. Control manual as well as automatic.
9. Heavy duty stainless steel pump.
Soft Flow Dyeing Machine
1. The vigorous agitation of fabric and dye formulation in the cloth increases the dyeing rate and
uniformity. It minimizes creasing as the fabric is not held in any one configuration for very long.
The lower liquor ration allows shorter dye cycles and saves chemicals and energy.
2. In soft flow dyeing machines the fabric is transported by a stream of dye liquor. However, the
transport is assisted by a driven lifter reel.
3. These machines use a jet having lower velocity that that used on conventional jet dyeing
machines.
4. The soft flow machines are gentler on the fabric than conventional jet machines.

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Winch dyeing machine
A dyeing machine consisting essentially of a dye vessel fitted with a driven winch ( usually
above the liquor level) which rotates and draws a length of fabric, normally joined end to end,
through the liquor.
Winch dyeing machine
Winch dyeing machine is a rather old dyeing machine for fabrics in rope form with stationary
liquor and moving material. The machine operates at a maximum temperature of 95-98°C. The
liquor ratio is generally quite high (1:20-1:40). Winch dyeing machines are a low cost design that
is simple to operate and maintain, yet versatile in application proving invaluable for preparation,
washing or after treatments as well as the dyeing stage itself. In all winch dyeing machines a
series of fabric ropes of equal length are immersed in the dye bath but part of each rope is taken
over two reels or the winch itself. The rope of fabric is circulated through the dye bath being
hauled up and over the winch throughout the course of the dyeing operation. Dyestuff and
auxiliaries may be dosed manually or automatically in accordance with the recipe method.
A winch dyeing machine
Description and Dyeing Method on Winch Dyeing Machine
The basic principle of all winch dyeing machines is to have a number of loops or ropes of the
fabric in the dye bath, these ropes are of equal length , which are mostly immersed in the liquor
in the bath. The upper part of each rope runs over two reels which are mounted over dyebath. At
the front of the machine, above the top of the dye liquor , is a smaller reel, which is called jockey
or fly roller.
The fly roller remains free wheeling along with fabric rope. At the back of winch tank is the
winch wheel, which pulls the fabric rope from the dye bath over the jockey reel for dropping in
the dye bath for immersion. From the dropped location, the fabric rope travels back. To be lifted
and fed to winch wheel.

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The dyeing process on winch dyeing machines is based on higher M:L as compared with other
dyeing machines. The process is conducted with very little tension. The total dyeing time is
lengthier as compared to other machines.
Advantages of Winch Dyeing Machine
1. Construction and operation of winch are very simple.
2. The winch dyeing machines are suitable for types of wet processing operations from desizing
to softening.
3. The winch dyeing machine is suitable for practically all types of fabrics, which can withstand
creasing in rope form processing.
4. Thr tension exerted on winch is less than jigger dyeing machine,the material thus dyed is with
fuller hand.
5. The appearance of the dyed goods is clean and smooth on winch dyeing machines.
Limitations of Winch Dyeing Machine
1. Batch dyeing operations needs trimming, sewing, opening out the rope , loading and unloading
for individual lots separately.
2. Since several lengths of fabric are run over the winch reel into the liquor and sewn end to
end,Continuous length processing is not possible in a single batch.
3. Fabric is processed in rope form which may lead to crease marks, particularly in heavy ,
woven , thin and light synthetics.
4. Most of the machine works under atmospheric conditions
Jet Dyeing Machine
This is the most modern machine used for the dyeing of polyester using disperse dyes. In this
machine the cloth is dyed in rope form which is the main disadvantage of the machine.
In this machine, the dye tank contains disperse dye, dispersing agent, leveling agent and acetic
acid. The solution is filled up in the dye tank and it reaches the heat exchanger where the
solution will be heated which then passed on to the centrifugal pump and then to the filter
chamber.
Jet Dyeing Machine
The solution will be filtered and reaches the tubular chamber. Here the material to be dyed will
be loaded and the winch is rotated, so that the material is also rotated. Again the dye liquor

47
reaches the heat exchanger and the operation is repeated for 20 to 30 minutes at 135o C. Then
the dye bath is cooled down, after the material is taken out.
Metering wheel is also fixed on winch by external electronic unit. Its purpose is to record the
speed of the fabric. The thermometer, pressure gauge is also fixed in the side of the machine to
note the temperature and pressure under working. A simple device is also fixed to note the shade
under working.
Advantages Jet Dyeing Machine
 Dyeing time is short compared to beam dyeing.
 Material to liquor ratio is 1:5 (or) 1:6
 Production is high compared to beam dyeing machine.
Disadvantages Jet Dyeing Machine
 Cloth is dyed in rope form
 Risk of entanglement
 Chance for crease formation.
Package dyeing machines
Package dyeing machines are the most widely used now a days for dyeing of almost all type of
yarns ,due to economical ,automatic and accurate dyeing results. The term package dyeing
usually denotes for dyeing of any type yarn wound on the compressible dye springs/perforated
solid dyeing tubes or cones. Yarn dyeing in package form is done at high temperature and under
high pressure ,with the packages mounted on hollow spindles .These spindles are fixed on the
dyeing carriers ,which is inserted into the dyeing vessel after closing the lid of the machine ,the
dyeing liquor is forced through the packages in two way pattern (inside to out and outside to in)
and goes on circulating throughout the vessel and yarn. Heat is applied to the dye liquor to
achieve the dyeing temperature, time –temperature and flow reversal are controlled through a
programmer.
Package Dyeing Machine
A series of technical developments in the recent years has resulted into package dyeing being
developed into a highly sophisticated as well as an economic process. Latest design Package
Dyeing machines are amenable to accurate control and automation. These features would likely

48
to lead to increases in the application of package dyeing.
The term package dyeing usually denotes for dyeing of yarn that has been wound on perforated
cores. This helps in forcing the dye liquor through the package. With the start of dyeing cycle,
the dye liquor goes on circulating throughout the vessel and tank. This happens till all the dye is
used up or fully exhausted. The dye flows through to the yarn package with the help of the
deliberate perforations in the tube package. Once full exhaustion is brought about, the carrier of
coloured yarn is consequently removed from the vessel. A large centrifuge removes excess water
from the packages. Finally the yarn is dried using an infra red drying oven. The image shows the
process working of a Package dyeing machine.
Working Process of Package Dyeing Machines
The material to be dyed is wound on the dye springs, perforated plastic cheeses or steel cones
and loaded in the carrier spindles ,which are compressed and bolted at the top to make a uniform
and homogeneous dyeing coloumn. The liquor containing dyes chemical and auxilliaries is
forced through with the help of pump, and circulated through the material from inside –out and is
reversed periodically so that each and every part of the material get the same and uniform
treatment. The dyeing cycle is controlled through a micro computer and different chemicals may
be added through the injector pump or color kitchen at any stage of dyeing.
In case of fully flooded machines ,the liquor expands with the rise in temperature (approximately
5% volume increases from 30-130 degree centigrade temperature) is taken back in the expansion
tank through a back cooler. This extra water is then again injected to the dyeing vessel through
an injector pump. Expanded volume of the dye liquor is thus remains in continuous circulation in
the system.
Any type of addition can be done to the machine through the injector pump, the quantity and
time of injection can be controlled through the programmer.
In case of air pad machines ,the air above the liquor acts as a cushion ,which is compressed with
the increase in liquor volume, the pressure is controlled by pre set pressure control valve .In air
pad machines have an advantage ,that entire dye liquor participate in dyeing and dye exhaustion
is perfect. In case some addition has to be done in air pad machines , if the machine temperature
is less than 80 degrees ,the liquor is taken back by back transfer valve to addition tank ,and
injected back to machine vessel. If the machine temperature is above 80 Degree then cooling has
to be done to bring down the machine temperature.
Air pad technology is possible in all types of machines such as vertical kier, horizontal kier and
tubular dyeing machines. The material after dyeing is washed and finished properly in the same
machine and taken out hydro extracted or pressure extracted in the same machine and dried
subsequently.
Advantages of Package Dyeing machine
Package dyeing methodologies have been subjected to intensive research and development. As a
result package dyeing machine has evolved into a very sophisticated apparatus. It offers a
number of advantages.

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Package Dyeing Machine
 Considerable reduction in yarn handling.
 Compatible to automatic control, in the process leading to reproducible dyeing‟s.
 Open to large batches.
 High temperature dyeing a possibility.
 Low liquor ratios, giving savings in water, effluent and energy.
 Uniform and High rates of liquor circulation, that leads to level application of
dyes. Machinery totally enclosed resulting in good working conditions at the dye-house.
Types of Package Dyeing Machines
Different type of Package Dyeing Machines are
1.Vertical Kier Dyeing Machines
2.Horizontal Kier Dyeing Machines
3.Tubular Dyeing Machines
Vertical Kier Dyeing Machines
These machines have a vertical cylindrical dyeing kier, in which material loaded into carriers
with vertical perforated spindles, is dyed .The machine could be fully flooded or air pad type
.These are high pressure machines and suitable up to 1350C temperature dyeing.
Horizontal HTHP Dyeing Machines
These machines are similar to vertical type machines in which the cylindrical dyeing kier is in
horizontal position. The dyeing carriers with vertical spindles are used in these machines, which
are inserted into the machine via trolleys. These machines are erected at the ground level and
hence do not needs an overhead hoist as well as platform, thus making the dye house design and
layout is simple.
Tubular HTHP Dyeing Machines
These machines may be of vertical or horizontal type, and have one or many tubes acting as
small dyeing vessels, each with a single individual spindle. The spindle is taken out of the tube,
loaded and then inserted back into it. These machines can be operated either fully loaded tubes or
to partial loads by using dummies. Since all individual tubes in a machine are connected and
serviced by a main pump, therefore it is also possible to operate as many tubes as required and
disconnecting others.
These machines can be erected at ground level and hence do not need a platform or hoist. These
machines are most flexible as for as the capacity variation is concerned ,without altering the
material to liquor ratio.

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Hydro Extractor:
Hydro-Extractors are also called Centrifuges. Centrifuges are used for water extraction
(dewatering, pre-drying) of textile materials. Values of approx. 15% for residual moisture
content can be achieved depending on the type of textile fiber. Centrifuges with perforated drums
or baskets (Ø up to approx. 2000 mm) which oscillate vertically in ball-and-socket joints
suspended on three points are produced in various designs as pendulating, suspension, cage and
vertical centrifuges, also with so called gliding support bearings as gliding support centrifuges or
in horizontal resp. vertical arrangements as open-width, horizontal and warp-beam centrifuges,
etc. Most centrifuges have electric drives for speeds of approx. 750–1200 rpm and are generally
provided with automatic control over various ranges. For safety reasons, an interlocking lid is
essential on a centrifuge so that the motor cannot be started until the lid is locked, nor the lid
raised until the basket is stationary again after the machine has been stopped.
Hydro Extractor
When used for dewatering loose stock, the cake of loose fibers is transferred from the dyeing
machine to the centrifuge and hydro-extracted before it is run into the fiber opener as a
preliminary stage of drying in a perforated drum drier. If an immersion centrifuge is used,
impregnation of the loose fibers with a spinning lubricant is also possible. In this case, the
material is loaded into the centrifuge, liquor is then pumped in (until it covers the material), and
the goods are finally hydro-extracted. The advantage of such a procedure lies in the fact that a
separate treatment of the textile material in an impregnation vat and the reloading of wet goods
into the centrifuge are eliminated . Impregnation of textile material in the impregnation basket of
a centrifuge is generally quicker and more effective for all processes than in a vat. The
centrifugal force which drives the liquor through the goods during centrifuging accelerates
penetration. It is possible to carry out several processes one after the other in an immersion
centrifuge. In this case, however, separate drain channels and liquor tanks must be provided. The
basket of an immersion centrifuge has an outer casing without perforations which surrounds the
cylindrical basket of a normal centrifuge (extended conically at the top). By this means, it is
possible to fill it with liquor to the level of the upper rim. Only when the basket is set in motion

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does the liquor, which is driven outwards by centrifugal force, rise up the basket casing and run
over the upper rim. Loose fiber material (loose stock) can also be centrifuged continuously. For
the dewatering of yarn packages, other possible options besides the asymmetrical dewatering of
columns of yarn packages in suitably shaped compartments of the centrifuge include
symmetrical dewatering by the rotation of individual packages or columns of yarn packages
which involves less risk of package deformation.
Technical Data:
1. Working width 1300mm
2. Machine speed 5~30M/min
3. Machine for the hydro extractor, softener, air ballooning type of cotton knitted
tubular fabrics without tension, with fabrics entwisting, air balloon, control of the
squeezing pressure and control of the final width of the fabric.
4. Automatic control of the feeding without tension, no edge mark, final folding without
stretching. Versions with simple or double squeezing and imbuing with softeners.
Advantages of Hydro Extractor:
 No deformation of the packages.
 Excellent rewinding properties. Rewinding can even be eliminated in a lot of cases.
 Low residual moisture.
 Even humidity distribution through the package.
 Low energy consumption.
 Dyeing tubes last longer.
 Processes many different size packages.
 Operator of centrifuge can also load dryer.
 Maintenance-free brakes.
 Closed system for effluent.
 Low compressed air consumption.
 Significant energy savings.
HTHP Beaker Dyeing Machine
HTHP Beaker Dyeing Machine is ideally suitable for sample dyeing of fabric and yarn at high
temperature and pressure. This machine is a versatile, compact and maintenance free apparatus
suitable for both Polyester and cotton sample dyeing. In fact it is suitable for dyeing of any fiber
in form. The apparatus is of immense use for dyeing and processing units research/testing
labs, textile engineering institutes and dyes manufacturers.

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Beaker Dyeing Machine
Features of HTHP Beaker Dyeing Machine:
1. The machine comprises of tank, beaker and gear box
2. The beakers are capable of withstanding pressure upto 6.0 Kg/cm square.
3. The machine is complete in stainless steel
4. Ensures a sound free and smooth working.
5. Microprocessor based programmer is provided which ensures temperature control.
6. Promises long life and leak proof service even after many years of use.
Specifications of HTHP Beaker Dyeing Machine:
 Standard Model : 12x250 ml., 12x100 ml., 6x500 ml., 12x500 ml.
 Electric Supply : Single phase 220 Volts, AC Supply
 Heater Supply : 3000 watt Single Phase
 Overall dimensions of the Unit : 700 ±05mm (L) x 470±05mm (H) x 370±05mm (W)
 Capacity of Beaker: 250 ml Beaker X 12 Pcs.
 Carriage Rotation: At 22 rpm. (±2 rpm)
 Maximum operating Temperature: 135°C.
 No. of Heater : 3 x 1500 W
 Maximum rate of heating: 1.50C
 Maximum rate of cooling 1.50C ( Water temperature max 250C )
 Net Weight of the Unit: 35 Kg.
 Net Weight of the Beaker (250ml): 10.980 Kg.
 Motor : Reversible Synchronous Geared Motor
 Medium used for Heating : Glycerine
 Beakers : 12x250 ml., SS-316 grade
Working Principle of HTHP Beaker Dyeing Machine:
1. First of prepare for dyeing piece by taking the sample fabric as per leakier ratio as
suggested by your quality consultant.
2. Sample moves up & down with auto forward and reverse direction through process
controller.
3. The machine must be cleaned at the regular intervals by changing water inside the
chamber.

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4. All bearings should be lubricated every three months.
5. Single phase motor contacts and Power contacts should be inspected every three months
Skein Dyeing Machine
This is the most suitable machine for dyeing delicate yarns (Silk, Bemberg, etc.) since it
prevents the material being too tightly packed; in fact other skein dyeing systems frequently
produce an excessive packing of the dyed material. The machine is equipped with horizontal
arms perforated in the upper part; skeins are stacked and suspended on this rack. The liquor,
forced through the arm holes, penetrates the skeins and is then collected in an underlying vat.
Standard machines are equipped with a rod which moves the skeins at preset times, changing
the bearing point to obtain a more uniform dyeing. During the skein motion, the flow of the
liquor is stopped to avoid the formation of tangles in the yarn; since yarns are not fixed to
rigid supports, they can thoroughly shrink. This machine does not run under pressure. It is
possible to dye at steady temperatures since the liquor is contained in a separate tank.
Skein Dyeing Machine
Modular skein dyeing machine with pullout arms. Pullout arms also allow the loading and
unloading of skeins far from the dyeing machine, without manually intervening in the

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intermediate dyeing, squeezing and drying operations. It can be used for silk, cotton, viscose and
Cashmere yarns.
The operating costs of this machine are generally very high because it require a very high liquor
ratio (1:15. 1:25. 1:30). Standby times for loading and unloading operations are also very high
and the arms must be often cleaned. This machine can be used also for scouring and finishing
processes.
Some machine manufacturers have designed machines with slant covers to avoid unwanted
liquor dripping on the skeins; the skein rotation is determined by the perforated arms, and not by
the rotation of the skein-lifting device when the arm is stopped; it is therefore possible to
eliminate the sliding contact with the skeins and preserve them perfectly.
There are also package dyeing machines with triangle-shape arms, arranged radially on a
variable-speed rotor. When the dyeing process has terminated, the material can be centrifuged
and dried, by forcing a hot air flow into the arms and through the skeins.
Equipment used in wet processing lab:
Wet Processing Lab:
Wet processing lab plays a vital role in the quality control of wet processing department. In
every wet processing lab mainly three types of tests are performed.
1. Tests for determination of the acceptability of chemicals for their intended purposes.
2. Tests for determination of several physical properties of the material.
3. Tests for determination of the quality of he finished materials.
4. Tests for determination of the quantity of dyes & chemicals required for a particular order.
When a new order is found; then the formulation of quantity of dyes & chemicals are prepared in
the wet processing lab. According to the recipe at first lab dyeing is done. If the obtained shed is
ok then sample dyeing is done in the floor. During sample dyeing different options are prepared
by slightly altering the quantity of dyes & chemicals. The sample is sent to the buyer for
approval. Buyer approves any one of the multiple options. Finally the recipe of the approved
sample is taken for bulk production.
After production the bulk is tested in the wet processing lab in order to ascertain wheatear the
finished products are confirming the requisite quality or not.
The instruments used in the dyeing lab are enlisted bellow with their purposes:
1. Oven:
Used for drying samples. It dries any sample by using micro wave.
2. Thermostatic Water Bath:
Used for extraction test. The samples are kept in Weing Bottle & are heated at required
temperature by this instrument.
3. Tear strength tester:
Used for testing the tear strength of sample (towel). Two samples from warp & two samples
from weft are tested & the average tensile strength of sample in warp & weft direction is

55
reported separately.
4. Crock Meter:
Used for testing the rubbing fastness of sample. The sample is clipped in the sample stand & a
staining fabric is clipped in the nose. Then the nose is rubbed against the sample for 10 times. At
first rubbing is done in wet condition, then again rubbing is done in dry condition with another
piece of staining fabric. Then the staining fabrics are assessed with standards & a grade is
assigned to the sample.
5. PH Meter:
Used for testing the PH of any solution. The PH meter is calibrated at first by using standard
solution. Then the sensor is dripped in to the solution that’s PH should be tested & the reading of
PH is shown on the display.
6. Hot Air oven:
Used for drying sample by using hot air.
7. Absorbency Tester:
Used for testing the water absorbency of towel.
8. Color Fastness Tester:
This instrument is used for three distinct tests. These are:
a. Color Fastness to Wash.
b. Color Fastness to Perspiration.
c. Phenolic Yellowing Test. This test is done in order to find out the presence of hazardous
component in the poly bag.
9. Oscillating Dyeing M/C
Used for lab dyeing in exhaust process.
10. Geyser:
Used for heating water at desired temperature that is used for various tests. It is provided with
separate pipes for feed & delivery of water. As it is mounted at a higher level so hot water can
easily be supplied due to gravity force.
11. Horizontal Padding Mangle:
It is a lab dyeing m/c of cold pad type. In this m/c the padding rollers remain horizontally;
therefore it is called Horizontal Padding Mangle. This m/c is used for sample dyeing. For dyeing
any sample at first the mangle is washed with water. Then dye liquor is taken to the bath. Then
towel sample passes through the liquor & then through the squeezing rollers. Then the sample is
kept covered with polybag for 12 hrs. Then the liquor is drained out & the m/c is washed again
with water.
12. Launder-O-Meter:
Used for assessing color fastness to non chlorine bleach.
13. AATCC Washer:
Used for washing any sample.
14. AATCC Dryer:
Used for drying samples. It dries the given sample in tumbling process in association with hot

56
air.
15. Tensile Strength Tester:
It is used for testing the tensile strength of sample. The Grab Test Principle is used in this m/c.
The m/c is provided with two jaws; one fixed (bottom jaw) & another movable (top jaw). The
sample is clumped between two jaws & then the m/c is started. As the distance between two jaws
increases; eventually the sample breaks. Tensile strength of the sample is shown on the digital
display in kg unit. Two samples from warp & two samples from weft are tested & the average
tensile strength of sample in warp & weft direction is reported separately.
16. Hardness Test Kit:
It is used for testing the degree of hardness in water.
17. Fume Hood:
This m/c has just taken in to the wet processing lab & yet it has not been erected. It is used for
testing different properties of dyes & chemicals.
17. Light Box Area:
It is used for finding out deviation of shed between the batch & reference. Here a dyed sample is
checked in the specific light recommended by buyer. The dyed sample is placed on the
observation board that inclines at 45o angle. Then it is compared either with reference fabric or
with reference pantone no. in the recommended light source visually.
The following light sources are usually recommended by the buyers:
 D-65
 TL-84
 UL-35
 UL-30
 CWF
Except the enlisted instruments, many other simple instruments that are used in chemistry lab;
are also used in wet processing lab. Those are enlisted bellow:
1. Beaker
2. Burette
3. Pipette
4. Glass Rod
5. Test Tube
6. Digital Balance etc
7. Decicator
8. Wine Bottle etc.
KNOWLEDGE IS POWER SAYED

57
DISPERSE/REACTIVE DYEING SYSTEM:
Disperse/vat dyeing system:
Typical dyeing recipe
 Disperse dye-X%
 Vat dye-Y%
 Dispersing agent-.5-1%
 wetting agent-.5-1%
 pH 4-5 with acetic acid (30%)
Procedure-
Prepare the bath with dispersing agent, wetting agent and acetic acid + treatment for 10-15min at
50-60°c then + disperse and vat + dye for 10-15min + raise temp up to 130°c in 60-90 min.
After PET part dyeing cool to 80c for proper levelling then add NaOH & Na2S2O 4 + dyeing
15min + cooling to 60°c + dyeing for 30 min. for better exhaustion Rinse with cold water +
oxidation with H2O2 for 15min at 50°c + Rinsing with cold water + Soap at 95° C for 25 min
using 2 g/l Lissapol D + Hot and cold rinse and then final wash off.
Only vat dyes which are stable up to 130°c can be used for this process.
One bath two step dyeing method-
All vat dyes may be used for the one –bath high temperature process provided that the dyes are
finely divided enough. The IK vat dyes are not preferred because the dye liquor requires to be
cooled to about 300c in order to obtain full colour yield. Therefore when IK dyes are to be used
it is preferable to dye by the two-bath process.
Typical dyeing recipe-
 Disperse dye-X%
 Vat dye-Y%

58
 Dispersing agent-0.5-1%
 Wetting agent-0.5-1%
 Ph-4-5(attained with 1-2 ml/l of 30% acetic acid)
Oxidation and soaping:
Oxidation and soaping can be be achieved simultaneously using the following recipe:
 Hydrogen peroxide(35%) 1-2 ml
 Anionic detergent -.5-1g/l
 Ph-9-10
First treat the material for 10-15 min. at 500c with hydrogen peroxide. Then the anionic
detergent and raise the temperature to 950c. Soap for 10-15 min.
 Method is used when selected vat dyes severely. It stain PET component during high
temp dyeing.
 Vat dye is added at 80°c after PET part dyeing rather than adding at the start with
disperse dye.
 Except it the whole process is same as the dyeing in one bath one step.
DISPERSE/REACTIVE SYSTEM
Same as one step dyeing except the addition of reactive dye at 80°c.
This process is used for the reactive dyes which are not stable up to 130°c, due to which they can
not be used in one step process
Thermosol Dyeing method:
 Continuous dyeing.
 Pad batch process.
Advantages of Thermosol dyeing-
 Continuous process so it gives higher production.
 Dye utilization is excellent.
 Dye can be used afterward.
 No carrier is required.
 Fabric is processed in open width form so natural feel of fabric do not get disturbed.
 No crease formation.
 Lower energy is required than batch.
 No extra heat setting is required

59
Disperse/vat dye system- PDPS method (Continious method)
ONE BATH ONE STEP THERMOSOL DYEING WITH DISPERSE AND REACTIVE
DYES:

60
CHEMICAL RECIPE & PROCEDURE:
Chemical recipe-
 Disperse dye-x g/l
 Reactive dye-y g/l
 Sodium bicarbonate or soda ash-5-20g/l
 Urea-100-200g/l
 Migration inhibitor-10-20 g/l
 Wetting agent- 1-2g/l
PROCESS-pad-dry-thermosol-cool-wash:
1. PADDING
 Padding Temp-20-300 c
 Liquor pick up-60-80%
2. DRYING
 First partial drying in infrared pre dryer and then fully drying.
 Partial drying is done to avoid migration of dyes.
 Drying is done at 120°c.
3. THERMOFIXATION
 It is done at 180-220°c, 30-45sec
 It is the fixation step.
4. PADDING
 Padding bath contain NaOH + Na2S2O4
5. STEAMING
 During this vat dye penetrated inside the cotton part. Then oxidation, soaping and finally
washing.
One bath one step dyeing process-Disperse/Reactive dyes:
 Padding in the second step is done using NaCl + NaOH
 H- Brand reactive dye is used.
 Fixation is done during steaming with saturated steam (102°c) for 30-60 sec.
 Then washing, soaping and again washing.
Recipe-
 Disperse dye-x g/l
 Reactive dye-yg/l
 Sodium bicarbonate or soda ash-5-20g/l
 Urea-100-200g/l
 Migration inhibitor-10-20 g/l
 Wetting agent- 1-2g/l.

61
NEW APPROACHES OF DYEING OF P/C BLEND FABRIC-
 Dyeing with Reactive Disperse Dyes in Supercritical carbon oxide.
 Dyeing of 80/20 PET/COTTON blend by using azeotropic solvent.
 Polyester/cotton blend fabric with sulphatoethyl sulphone disperse /reactive dye
treatment.
 One-bath dyeing PET/COTTON blend with azohydroxypyridone disperse dye containing
a fuluorosulfonyl.
Dyeing with Reactive Disperse Dyes in Supercritical carbon oxide:
What is supercritical CO2?
 It is a naturally occurring that is chemically inert, physiologically compatible, and
relatively inexpensive.
 It is nonflammable, it is supplied either from combustion process or volcanic process
without the need of producing new gas & it is recycled in a closed system.
 No disposal problem.
 Easy to handle.

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