What Is Thermosol Dyeing Machine?

What Is Thermosol Dyeing Machine?

Thermosol Dyeing Machine

Thermosol dyeing machine helps to improve production capacity. It does not required rotation after padding. It must feed on pad steam for fixation just after dyeing which gives finished product. It is a dyeing machine but it can not produce the color as finally required or permanent. But in PDC process it can provide finished product. By this machine only color is migrated from liquor to fabric. Then it is dried on pre dryer & followed by hot air flow drying in thermosol unit. After this process color is developed in pad steam by chemical padding.

M/c specification:

Brand Name: Monfort Montex

Origin: Germany

Flow chart of Thermosol Dyeing Machine

Fabric inlet

J- Box

Dye Padding

VTGR (Airing Zone)

IR Dryer-1 + 2

Drying Unit

Curing

Cooling Cylinder

J- Box

Fabric Outlet

Sections of Thermosol Dyeing Machine

Thermosol Dyeing Machine  – Fabric inlet section: After mercerizing batcher is feed into the inlet of thermosol machine. Where the fabric is passed over some free roller, parpet roller & platter. Here there is a compensator to control fabric open width entry & controlling fabric speed.

Thermosol Dyeing Machine - Fabric inlet section
Fabric inlet section

Thermosol Dyeing Machine  – Cooling roller:If the fabric comes in thermosol just after mercerizing, the fabric remains hot. When it will feed on thermosol machine it can increase temperature of chemical bath. So cooling roller is essential

Thermosol Dyeing Machine - Cooling roller
Cooling roller

Thermosol Dyeing Machine  – Chemical Mixing tank:In thermosol machine only dye stuff & wetting agent & migrating agent is used. Dyes are dissolved separately from wetting & migrating agent then all are forced to chemical storage tank as required & agitated for proper mixing.

Thermosol Dyeing Machine - Chemical Mixing tank
Chemical Mixing tank

A typical recipe for thermosol process

Recipe for Reactive Dye:

Fabric construction:- 108 X 52 / 45 X 34/2

Nova yellow CRG = 0.76 gm/l

Nova Red C- 2 BL= 0.72 gm/l

Nova Blue CR = 0.53 gm/l

Primasol-v = 10 gm/l

Primasol-NF = 2 gm/l

Urea          = 50 gm/l

Soda ash   = 10 gm/l

Fabric Speed – 5o m/min

Temperature – 120 -130°C

Recipe for Disperse Dye:

Fabricconstruction:- 133 x 60 / 20X 16

Nova yellow S3R = 4.80 g/l

Nova red S3R     = 5.90 gm/l

Nova navy SG     = 14.40 gm/l

Soda ash = 15 gm/l

Urea = 100 gm/l

Primasol-v = 10 gm/l

Primasol-NF = 2 gm/l

A typical recipe of W/W dye:

Padder pressure = 3 bar

Speed                = 3m/min

Steaming           = 1.5 min

Nova yellow NC = 5.84 gm/l

Nova brown NC = 2.04 gm/l

Nova blue CD    = 2.9 gm/l

R.salt               = 3 gm/l

Glubar salt       = 10 gm/l

Soda ash          = 10 gm/l

Wetting agent   = 2 gm/l

Thermosol Dyeing Machine  – Dye Padding Unit:Here chemical comes from storage tank to maintain even range on padding tank. Here three bowl padding is occurred. During padding the most common problem of dyeing “listing problem” can be solved by adjusting pressure on left, right & middle of padder. The layer of dyes keeps up to 50 liter & automatically dyes is come to dye bath.

Thermosol Dyeing Machine - Dye Padding Unit
Dye Padding Unit

Thermosol Dyeing Machine  – VTGR (Airing zone): After dye padding before enter in to IR dryer unit, the fabric is passed through airing zone. Where fabric is conditioned by open air.

Thermosol Dyeing Machine - VTGR (Airing zone)
VTGR (Airing zone)

IR dryer: After airing zone fabric pass over some free roller then enter in IR dryer. It is called pre dryer. Here temperature is around 650-750’C.it can differ based on fabric speed & type of fabric is processing. In thermosol there are two IR unit & each contain two heating zone(flamer). Here fabric is dried up to 40%.

M/C Name: Maxon

Inlet pressure: 80 bar

Heat input: 483 kw

Type of gas: Natural gas

Hot air flow drying unit:Fabric comes to this unit after predrying. Here there are three unit of heating. Each contains two heater (gas type) & two blower. Temperature is taken is around 80-150’C. If this flamer & blower is not work properly it will create listing problem. Here there are few additional options like humidity control unit & cleaning unit. When pad dry cure is performed in thermosol then humidity must be controlled. If it can control, no need to use urea. Fabric contains different types of dust so when hot water is blown it can make problem in heater & blower. So there is a screen unit so that dust can not goes in blower or heater. Smaller particles can be taken out trough duct & release to environment. Here 30-35 meter fabric is remain.

Curing chamber:After drying the fabric is passed through curing chamber. Here the fabric is heated from 150-170’C in case of reactive & in case of disperse 200-210’C. In this chamber there are four layer of roller. And in this roller 80-85 meter fabric is remain for proper heating & fixing the color of fabric.

 Cooling roller:After hot air flow drying fabric require a cooling. So fabric is passed over the cooling roller. It is a stainless steel roller through which cold water is passed. There are two cooling roller.

Thermosol Dyeing Machine  – J-Box:It is a space for keeping fabric. When the batch is completed, it is needed to change & another empty batch roller is to be settled. Due to continuous dyeing process it is not possible to stop the m/c. So during changing batch roller the fabric is stored in J-BOX. And when new empty batch roller is settled, then the fabric is started to batching.

Thermosol Dyeing Machine - J-Box
J-Box

Thermosol Dyeing Machine  – Fabric outlet:Finally fabric is passed over batching roller & batched on batching roller. Then it becomes ready to feed in pad steam in chemical padding.

Thermosol Dyeing Machine - Fabric outlet
Fabric outlet

Thermosol Dyeing Machine  – Control Panel:From control panel all types of instruction can be provide to the machinery. This machine has a full manual control panel. The operator controls every process by control switch.

Thermosol Dyeing Machine - Control Panel
Control Panel

Testing required during Thermosol operation:

  1. Pick up testing
  2. Shade listing identification.

Pick up testing:Before going to thermosoling pick up of the fabric should be calculated & based on this result liquor is prepared.

Thermosol Dyeing Machine  – Shade listing identification: After each 1000 meter shade is tested in light box. Here listing problem is visualized & can be solved by increasing or decreasing left, centre or right padder pressure. Suppose in left color is lighter then lower the pressure of left side.

Thermosol Dyeing Machine - Shade listing identification
Shade listing identification
How Mercerizing Machine Works for Mercerized Cotton Yarn

How Mercerizing Machine Works for Mercerized Cotton Yarn

Mercerizing Machine

Mercerizing machine is a process for increasing absorbency, strength, and lustier of the fabric by physio-chemical treatment. And this chemical treatment is occurred in two IMP-1 and IMP-2 bath by passing the fabric into a airing zone. John Mercer, a person was the first chemist in the world who found this phenomenon in 1844.Therefore the process of this type of wet processing was called Mercerizing.

Objectives of Mercerizing Machine

To make the goods more luster because raw cotton fibers are ribbon-like. After this process, the fibers change to cylindrical shape, resulting more evenness reflected light from the goods.

Objective of Mercerizing Machine
Before                                                          After

To improve dye ability of the goods about 5-10%.

Specification of Mercerizing Machine

  • M/c name: Mercerize m/c
  • Brand: Goller
  • Origin :Germany
  • Speed:60 m/min
  • Capacity :1 lac m/day
  • Expander roller: Remove dirtness and keep the fabrics in level Padder Upperb padder: made by rubber Check hardness : 80-90%, Lower padder: made by AUTO Check hardness : 100%
  • Dancing roller: Tension keeps proper before going on dryer.
  • Caustic temperature : 35-55’C
  • Vacume pump(air): Remove water
  • Padder pressure: 3bar-washing, IMP-1 & IMP-2—3.5bar
  • IMP-1 :Strong lime with 30’ baume Solid caustic + 28’ baume mercerize oil.
  • IMP-2 :Here shrinkage is controlled by using caustic and mercerizing oil. Airing zone: In airing zone = 11 air roller/8 air rollerIn airing zone, fabrics are dried by air and chemical is added with fabrics.
  • Gear+chain : Maintain width, control shrinkage in weft And caustic is utilized in every fibre equally.
  • Tanki : No. of tanki-5These keeps water hot and creates weak line (8baume)
  • Washing chamber (1-3): Hot wash 90’c
  • Washing chamber 4: Wash at room temperature
  • Cylinder dryer temperature : 110=-130’c
  • Cooling dryer temperature : 25-40’c
  • Exact roller : Maintain fabrics that, selvedge does not remain straight.Using acid according to fabric GLM -1. 300+GLM thick- 100% acid, 2.      140-274 thickness- 50% acid + 50% water
  • Types of mercerizer : 1.cool mercerizer – 18’ baume . But for cool mercerizer good chellers  are needed. 2. Hot mercerizer- 28-30’ baume
  • Recipe: Sodium Hydroxide (NaOH) –  (28±2)º Be (Baume´) 267 gm/l (see note) Steam, water  –    As required, Green acid / Nurta acid (32%) – 3-4 % of total water, Wetting agent-  1-1.5 gm/l,
  • Compressed air -:  As required
  • Mercerizing Oil (Mercirol QW2F) : 3-4 gm/l
  • Tests : Barium activity test, 2.PH, 3.         Absorbency , 4.           Size chemical Suitable For All cotton fabric, TC/CVC fabric, Twill Fabric

Flow chart of Mercerization

Fabric inlet

J-Box

Impregnation-1(IMP)

Airing Zone

Impregnation-2(IMP)

Gripping Chain

Stabilizing Compartment

Washing Chamber 1 2 3

Neutralizing chamber

Drying unit

J-Box

Batching

Operational Procedure for Mercerized Cotton Yarn:

Fabric inlet for mercerized cotton: Batcher from scouring & bleaching unit is feed into the inlet of mercerizing range. Where the fabric is passed over some free roller, guider & expander. Here there is a compensator to control fabric open width entry.

Fabric inlet for mercerized cotton
Fabric inlet

Chemical mixing tank for mercerized cotton: Caustic is mixed in a separate mixing tank. Here 30 BAUME concentration is ensured. It is ensured by mixing 300 kg caustic in 1000 liter water. BAUME can be adjusted by adding water or additional caustic. Then wetting agent & caustic is forced to main chemical mixing tank from which it goes to chemical tank to maintain uniform chemical height in the tank.

Chemical mixing tank for mercerized cotton
Chemical mixing tank

Impregnation-1(IMP) of Mercerizing Machine : Fabric comes to Impregnation-1 from inlet through guider & series of driven, free roller. In mercerizing process the only wetting agent & caustic is used. Temperature is around 60’C.

Airing zone of Mercerizing Machine : Fabric is passed over the Airing zone after chemical padding. Here there is no application of temperature & pressure. It involves 4 rollers which are driven by motor. This application is only for drying in contact of air which facilitates more chemical consumption from next bath

Impregnation-2(IMP): same as Impregnation-1(IMP). After that squeezing is occurred.

Gripping chain for mercerized cotton: from Impregnation-2 fabric pass over the free roller & comes in to chain for gripping. Here the fabric is stretched for control width. If crease mark is found from previous process, that can also be controlled by stretching. Here there is an additional option of showering by hot water. Which ensure proper cleaning & removal of residual caustic.

Gripping chain for mercerized cotton
Gripping chain

Stabilizing compartment : Below chain where hot wash occurred there is chamber for collecting caustic containing hot water. That is driven to caustic recovery plant for making it ready to mercerize chemical once again.

Washing chamber(1 2 3) for mercerized cotton: From chain by squeezing fabric comes directly to washing chamber. Here fabric passed over some driven roller to make proper hot wash. There are 3 hot wash chambers that are linked with one another & horizontally inclined. Here temperature is maintained is around 90’C.

Washing chamber(1 2 3) for mercerized cotton
Washing chamber

Neutralizing chamber: after washing fabric goes through neutralizing chamber. Caustic make the fabric highly alkaline so that is neutralized by the addition of acetic acid. For controlling ph from control panel a command is given such as 7. Then the fabric will takes this amount of acetic acid which makes the fabric neutral by maintaining ph 7.

Dryer for mercerized cotton: After washing & neutralizing for drying process 2 stage vertical cylinder dryer is used. It is heated by steam. For course fabric the cylinder dryer temperature  is around 180-200’c. and for pocketing fabric the cylinder dryer temperature is around 110-130’c.

Dryer for mercerized cotton
Dryer

Batching : Finally after drying the fabric is ready to dye. It is now rolled in the batcher for next process.

Barium Activities Test:

Barium activities test is done to know about the increasing % of absorbency of fabric & depth of luster. By barium activity we can also see that, after mercerizing remaining wax oil and other impurities are removed &strength is increased.

Formula:-

Blank Ba(OH)2 – A/M Ba(OH)2

Barium Activity%=————————————- x 100

Blank Ba(OH)2  – B/M Ba(OH)2

Process: The Barium activity test is done in two processes—

  • Chemical test
  • Application test

In this test only barium is used. So it is called barium activity test.

1) Chemical test:

Recipe:

Fabric = 5 gm

Soda ash = 2 gm/l

Detergent = 10 gm/l

Ba(OH)2  = 30 gm/l

Sample: a) One from before mercerization

  1. b) Other is mercerized fabric

Procedure:

  • Taking 5gm fabric sample
  • Adding 2gm soda ash & 10 gm/l detergent
  • Then boiled for 1 hr
  • After boiling, hot wash
  • Then drying is done for 1min at 140°C
  • 2gm fabric is cut from both sample (App. 1’’ square)
  • Then the samples are dissolved in 30ml Ba(OH)2 solution (0.25 N)separately & kept for 2 hour.
  • Then we will have to titration.

To do titration 0.1 N HCl is used.

For Blank Ba(OH)2  = 10ml (From 30ml)

For A/M Ba(OH)2    = 10ml (From 30ml)

For B/M Ba(OH)2   =  10ml (From 30ml)

Now from taking the reading of burette we get the barium activity % from the above equation.

21 – 17.8

B.A % = ————–X 100

21 – 18.6

= 133%

  1. b) Application test:

Recipe:

Dye (Remasol deep black R.G.B) = 70 gm/l

Soda ash = 20 gm/l

Urea = 200 gm/l

Primasol – V = 10 gm/l

Primasol NP = 2 gm/

Remarks: In preparation section fabrics are prepared for dyeing by increasing whiteness, absorbency, removing impurities etc.

Dr. Joshep, DGM, Textile Division, Seotex Limited, USA
Define Scouring Machine. What is Bleach Chemical Formula

Define Scouring Machine. What is Bleach Chemical Formula

Define Scouring Machine

The process to remove the fats, oil, and waxy substance and added  other impurities by certain percent of alkali and which increases the absorbency power of the textile goods is called scouring machine . Scouring machine is used for removing the natural as well as added impurities as completely as possible. To provide a clean material by adding alkali,  To leave the material to a highly absorptive condition without undergoing any physical & chemical damage and  To make fabric suitable for next process etc.

Scouring Process

The main changes soccurring during scouring:

  1. Saponifiable oils & fatty acid are converted in to soap & peptic acid.
  2. Pectin & pectoses are converted into soluble salt & peptic acid.

iii. Proteins are degraded into simple soluble amino acid.

  1. Mineral matters are dissolved
  2. Dirt is removed.
  3. Sizing materials are broken down into soluble product.
sketch diagram of Scouring and bleaching
Sketch diagram of Scouring and bleaching

Chemical used in scouring

  • Caustic (Na0H)
  • Wetting agent.za

Bleaching Machine

The process of bleaching machine by which the natural color of a fibre can be removed and make the textile materials pure white and bright is called bleaching. Objective of bleaching machine is to provide permanent whiteness, To increase absorbency of fabric,  To prepare fabric ready for next process.

Example of some bleaching agent

  • Oxidizing –agent reducing agent
  • H202 –zinc dust
  • Na0Cl –carbon (c)
  • NaCl02 –hydrogen (H)
  • Ca (0Cl) –2S02
  • Bleaching powder –NaHS04
  • KMn04

Bleaching with hydrogen peroxide (H2O2)

  • H2O2 is a colorless clear liquid
  • It should stored away from light
  • In presence of heavy metal it decompose with the liberation of oxygen.
  • The material is irritant for skin.

Machine Specification:

  • M/C name: scouring machine and bleaching machine
  • Origin: Germany.
  • Capacity: 70-80 thousands meter/ day.
  • Speed: 50-60 m/min
  • Pressure(bar): Air- 50 bar
  • Steam- 7 bar
  • Washing temperature: W 1+2 =98’c, W 3= 70’c, W 4 -7= 98’c, W 8= 90’c
  • Steamer temperature: Steamer
  • Steamer 3 = 103’cSteamer timing: For  White Fabrics- 26 mins, Yarn dyed- 24 mins, Vat dyed- 12-14 mins, Only for scouring- 18 mins
  • Padded Pressure: 2.5 – 3 bar
  • But in washing chamber, W-3 and W-8 = 2.5 and W-1, W-2, W-4, W-5, W-6, W-7 = 3
  • Drying r/r temperature: 130 -140’c
  • Cooling dryer temperature: 25-30C
  • Fabric condition: whiteness – above 78% yellowness – 1 or below 1, But incase of OBA, whiteness – 100%, yellowness – (-22%), Standard- 15%

Flow chart of Scouring Process

Fabric inlet section

Washing chamber 1 2 3

Vacuum suction unit

Chemical mixing Unit

Chemical chamber

Steamer

Washing Chamber 4 5 6 7

Drying Unit

Batching Unit

Scouring Machine and Bleaching Machine Scouring Process:

In continuous scouring & bleaching the following steps are followed.

Fabric inlet of Scouring Machine and Bleaching Machine: After rotation of batcher it is feed into the inlet of scouring & bleaching range. Where the fabric is passed over some free roller, parpet roller & platter. Here there is a compensator to control fabric open width entry.

Fabric inlet of Scouring Machine and Bleaching Machine copy
Fabric inlet

Washing chamber of Scouring Machine and Bleaching Machine 🙁 1 2 3) Fabric comes in open width & entered in washing zone. Here there are three chambers for removing water soluble decomposed starch. Here temperature is maintained is around  1st & 2nd 98’C and 3rd chamber 70’c. Then fabric is passed in chemical chamber after squeezing where pressure is maintained approximately 2.5-3 bar.

In every washing chamber, there are two pressure bars-

  1. one for compressor roller
  2. other for padded roller

Vacuum suction unit of Scouring Machine and Bleaching Machine : With washing unit 1&2 a vacuum suction unit is connected. In this unit through air suction the inferior particles are collected & moved out through duct.

Vacuum suction unit of Scouring Machine and Bleaching Machine
Vacuum suction unit

Chemical Chamber of Scouring Machine and Bleaching Machine: In chemical Chamber both scouring & bleaching is occurred. Recipe is setted according to its requirement. In chemical bath temperature remains as bath like room temperature. Here a Doctor blade is used to add chemicals in fabrics evenly. A typical recipe is given below:

Steamer of Scouring Machine and Bleaching Machine: After chemical padding the fabric is directly goes through the steamer. Here temperature is 104’C approximately. Here fabric stays for 12 to 26 minute. This depends on type of fabric & operational speed as well as quality required.

Steamer of Scouring Machine and Bleaching Machine
Steamer

Chemical feeding of Scouring Machine and Bleaching Machine: beside chemical bath there is a chemical mixing tank. Chemical comes  from individual storage according to setting and add with water finally agitated and pumped into chemical tank.

Chemical feeding of Scouring Machine and Bleaching Machine
Chemical feeding

Washing chamber (4 5 6 7 8) of Scouring Machine and Bleaching Machine : After steaming in steamer fabric pass through the washing chamber once again. Here temperature is maintained is around 4 to 7 is 98’c and 8 no. chamber is 80’c  After every washing bath there is a squeezer having pressure approximately 2 to 2.5 bar.

Neutralizing chamber: After washing there is a option of neutralizing. Here neutralizing is done by acetic acid. But those fabric which will be mercerized need not to neutralized. That will be done at mercerizing stage.

Cylinder dryer of Scouring Machine and Bleaching Machine: scoured & bleached fabric is finally passed through the drying unit. It passes through two stage cylinder dryer.

Cylinder dryer of Scouring Machine and Bleaching Machine
Cylinder dryer

Cooling roller of Scouring Machine and Bleaching Machine: Dried fabric is passed over two cooling roller. It is cooled by cold water passing through roller by contact of which fabric become cool.

Cooling roller of Scouring Machine and Bleaching Machine
Cooling Roller

Batching: finally the fabric is rolled in batcher. Then it is feed as a raw material of mercerizing machine.

Recipe:

For all color-

  1. Sequestering agent: – 2g/L
  2. NaOH : 40g/L

iii. H2O2 : 45g/L

  1. Stabilizer : 8g/L (catalyst)
  2. Wetting agent: 8g/L

For pocketing fabric

  1. Sequestering agent: KEB- 2g/L
  2. NaOH : 20g/L

iii. H2O2 : 30g/L

  1. Stabilizer : GAL 8g/L (catalyst)
  2. Wetting agent: RGN-8g/L
  3. Dearting agent: ASN- 2g/L
  1. Timing of chemical chamber: 20-30 mins
  2. Timing of steamer: 30mins
  3. ph: Washing chamber 1-3=7.5-8

Washing chamber 4=11

Washing chamber 5=10

Washing chamber 6=9

Washing chamber 7=8

Washing chamber 8=7.5

Strength of chemicals: NaOH: 30-40 baume

Pick up%: L= 110.3

C=112.42

R=111.56

Caustic specific gravity: 1.2

Clibration: Calibration is done according to timing.

Amount of chemical/ min=Fabric G.L.M× Recipe%×Speed/1000

Effect of ph:

Ph<10 – active as bleach

Ph 10.2- 10.7 – is optimum for controlled bleaching.

Ph 11.b – bleaching is out of control.

Scouring & bleaching in same bath:

In Auto Textile  bleaching and scouring are done in combine process which called solomity process.

In Auto Textile  the Scouring & bleaching can be occurred in the same bath. It will reduce time as well as provide same quality. For that procedure as additional chemical stabilizer should be used.

Bleach Chemical Formula

It is the process used for identifying the amount of chemicals present in the solution. In solemnity process titration is done for caustic & hydrogen peroxide.

Titration process of NaOH:

  • Key Accessories:- Burette, Pipette, Beaker etc
  • Standard solution:- 0.1N HCl
  • Reagent:- Phenolpthelene indicator (1%)

Procedure:

  • 1ml mixer solution or chemical solution is taken from the mother tank in a chemical flask.
  • 20ml water is added with the solution and stirred for a few seconds.
  • 2-3 drods phenopthelene indicator is taken.
  • To do titration 0.1 N HCl is used.
  • The number of drops of 0.1 N HCl is used to calculate the amount of NaOH present in the mixing tank.

Result:

Amount of NaOH = Reading X 4

Titration process of H2O2:

1) Key Accessories:- Burette, Pipette, Beaker etc

2) Standard solution:- H2SO4

3) Reagent:- 0.1N K2MnO4

Procedure:

  • 2ml mixer solution or chemical solution is taken.
  • Adding 10ml H2SO4(25%)
  • Taking 0.1 N K2MnO4in a burette
  • The number of drops of 0.1N K2MnO4is use to calculate the readings until the solution turns in to light pink color.

Result:

H2O2 (% or gm/l) = 3.4 X reading

Baum Test (OBe):

A scale used for measurement of the relative density (RD) of liquids by hygrometry.

Bleach Chemical Formula

To make a specific strength of a chemical i.e. Caustic soda we can formulate as like —

OBe x 10

Strength (OBe) of NaOH = ————- x 100

1000

But this formula is used for 100% pure NaOH. But in case of impurities (5-10%) tolerance is kept.So the conversion of strength measure of caustic soda solution–

Strength (OBe)Slid caustic soda content (g/l)
30350
40480
32373.33
50583.33
   37.5430
48560

PH find out test:

1) Drop method:-

  1. Chemical name: Universal indicator solution
  2. Color scale: Integrator scale.
  3. pH range of scale: 4-11

More Bleach Chemical Formula Procedure: a single drop of indicator solution is fall down in to the fabric and given                                                                            5 seconds for measuring. Then the color of round shape is matched with the color scale.

2) Core test:- Core test is done to find out pH.

Key accessories:

  • 8m fabric
  • 200ml water
  • pH meter
  • Seizer

Procedure:

  • At first 8gm fabric is cut in every small piece.
  • Taking 200 ml water in a vessel & boiled for 10min
  • After 10min 8gm fabrics are added to the boiled water & boiled for 10min.
  • Then kept for conditioning at room temp. (4 hour)
  • After 4 hrs pH meter is used for measuring the pH value.

Here saturated kCl solution is used to immerse the electrode & distilled water wash it & for calibration pH 4, pH 7, pH 10, are used. It is an one type Dyeing Machine

Prof. Dr. Morisas, Head of Wet Processing Dept, University of Textile And Apparel, UK
How Singeing Machine and Desizing Machine Works

How Singeing Machine and Desizing Machine Works

Singeing Machine

Singeing machine is the process passed out for removing loose hairy fiber protruding from the surface of the cloth there by giving it a clean looking surface. If the fabric is to have a smooth finish than singeing is essential. Singeing and desizing is a dry process used on woven goods that removes the fibers protruding from yarns or fabrics.

Singeing Machine and Desizing Machine
Schematic Diagram Singeing Machine and Desizing Machine

These are burned off by passing the fibers over a flame or heated copper plates. Singeing and desizing improves the surface appearance of woven goods and reduces pilling. It is really useful for fabrics that are to be printed or where a smooth finish is desired. Pollutant outputs associated with singeing include relatively small amounts of exhaust gases from the burners.

Objective of Singeing Machine

  • To remove loose hairy fibers.
  • To obtain a smooth Surface.
  • In order to impart a clearly defined & sharp design.
  • To prepare fabric for next process.

Desizing

The process to remove the size material applied in weaving section and increase the absorbency power of the fabric is called desizing.

Desizing unit
Desizing unit

Machine specification

  • Gas singeing machine:
  • Name: Osthoff-(Senge-Desize m/c)
  • 42327 wuppertal
  • Bj-1994
  • Model-pk94
  • No-6400
  • Origin: Germany

Machine description with process

Fabric inlet section: Gray fabrics are directly feed into the inlet of singeing machine. Where the fabric is passed over some free roller, guider & expander to ensure open width entry. Here there is a control panel to control fabric speed.

Singeing Machine Fabric inlet section
Fabric inlet section

Cleaning unit 1: Through fabric inlet then fabric is passed through cleaning unit which contain a brush as well as provide a vibrating motion for effective cleaning. From this unit dust are collected through duct in which suction is occurred by a high power motor. Big dusts are collected in dustbin and inferior particles are released in environment.

Singeing Machine Cleaning unit 1
Machine Cleaning unit

Singeing unit: After passing cleaning unit then fabric comes into contact of flame for singeing. Fabric is passed over the water roller & in water roller flame is attacked tangentially or horizontally depending on fabric type & quality required.

Singeing Machine Unit
Machine Unit

Cleaning unit 2: when singeing is occurred, the fabric contains few flame sparks on its surface & selvedge. Those are removed by cleaning unit & the dusts are passed through water because they contain fire spark. The inferior particles are moved away through duct in environment.

J Box: if fabric is feed as roll form then two j box is required one after inlet & another before cleaning unit. In continuous process j box is required for the continuity of fabric processing without machine stoppage which saves time.

Singeing Machine J Box
Singeing Machine J Box

Desizing unit: finally the fabric is passed through desizing unit. Its contain desizing liquor. For desizing wetting agent, Enzyme, sequestering agent, acetic acid is required. Temperature is maintained around 80-100’C.

Chemical mixing unit: Beside desizing unit there are two chemical tank one of them is called reserve tank where chemical is mixed & circulated, another is storage tank where agitated chemicals are stored for using in bath. From this chemical entered in bath as required for even immersion.

Singeing Machine Chemical mixing unit
Chemical mixing unit

Batching unit: After desizing fabric is collected in rolled in batcher in uniform tension. Then the fabric goes for rotation of 10-12 hours. For proper decompose of starch it is essential.

Singeing machine - Batching unit
Batching unit

Rotation: After batching the fabric is packed by poly bag. Then it goes for rotation for 8 to 12 hours. In this time water react with starch in presence of enzyme & decomposestarch as water soluble glucose.

Rotation after Desizing
Rotation

A typical Recipe for Desizing

Solid dyed fabric desize Recipe-

  1. Wetting agent: Rucolase F.W.K– 7 gm/lt
  2. Enzyme: Rucolase H.C.H – 8 gm/lt

iii. Dearting agent: Rucowet V.L-1g/lt

  1. Sequestering agent: Verolaw N.B.O – 1 gm/lt
  2. Acetic acid – as required to maintain pH

Yarn dyed fabric desize Recipe-

  1. Wetting agent: Rucolase F.W.K – 5 gm/lt
  2. Enzyme: Rucolase H.C.H – 5 gm/lt

Here,

  1. Enzyme: Enzyme can make soluble the sizing chemical in H2O.
  2. Wetting agent: it is used to increase the wettability of textile substrate and dye-stuff in water to easy penetration and obtain smooth paste. i.e.  T.R oil.
  3. Sequestering agent: It is used to minimize the impact of hardness of the water. i.e EDTA.
  4. Dearating agent: It is used as antifoaming agent and increase the penetration of  wetting agent.

Note:   – In woven fabric processing Gas singeing machine is widely used.  -The singeing is not applied above 45 count of fabric.

Material and Chemical used

Steam, compressed air, water, natural gas, Desizing agent, wetting agent, sequestering agent and dearating. Sizing Machine also work similar process.

Check list before production

Operator must check the following before starting production of the fabric named bellow:

  1. All cotton colored fabric = Singing & Desizing.
  2. All cotton colored peach finish fabric = Desizing.
  • Yarn dyed & P.C/C.V.C fabric = Singing & Desizing.
  1. P.C/C.V.C fabric = Singing & Cold bleach.
  2. P.C/C.V.C / yarn dyed peach finish fabric = Desizing.
  3. Bull-Twill / Heavy fabric = Singing & Cold bleach.
  • White cotton fabric & Special yarn dyed (PC-015) fabric = Singing (Without Chemical)

Basic parameter of m/c

  1. Fabric Speed: 80m/min

But normally 65-70m/min

  1. Flame intensity:

For fine fabric= 10-11 mbar

For coarse fabric= 16-17 mbar

For pocketing fabric= 6-7 mbar

Some condition for Flame intensity

GLM: 410-570= 18 mbar

GLM:300-400= 16 mbar

GLM:180-274= (14-15)

GLM: 100-132= (8-10)

Note: When tension is increased  flame intensity is also increased . Otherwise flame intensity is decreased with low tension.

  1. Pick up %:

For coarse fabric mainly taken-100%

For fine fabric mainly taken-80%

  1. Temperature: Bath – 50’c
  2. Cold bleach:cold bleach is done at room temperature.
  3. Chamber temperature: 85-100’c
  4. PH-6.5
  5. Desizing temp- 80-100’C

Flow chart of Singeing & Desizing

Fabric inlet

Cleaning unit 1

Singeing unit↓

Cleaning unit 2

J Box

Desizing unit

Batching Unit

Rotation

Here also has,

  1. Compensation roller: If compensation rollers down fabrics move and if compensation roller up fabrics fixed.
  1. Bow roller: which is moved ups to downs.
  2. Padded: only squeeze is done.
  3. Free rolle
  4. Bend pipe: Shrink will not occur
  5. Padded Pressure: Maintain tension.
  6. Sochor roller

Pick up%:

The total amount of chemicals which are absorbed by fabrics.

It is the ratio weight (wet fabric to dry fabric) to dry fabric and expressed in percentage.

Formula :

Wet fabric – Dry fabric

Pick up% =                                                                                         × 100%

Dry fabric

Procedure of Singeing Machine and Desizing Machine

  • pick up% is measured from left, centre, right.
  • At first 3 sample are cut from the above of padder pressure or                               after squeeze roller.
  • Then the samples are packed in polybags with vapour
  • We will have to take the weight of polybag frome left, centre and right side.
  • Then we take the weight the fabrics with poly
  • By removing the value of 2nd to 1st value , we get the value of /weight of wet fabrics
  • Then the samples are washed by 1-2% CH3COOH and water
  • To dry these, we will have to give samples in the oven. i.e Rapid (Labortex Ltd)
  • After drying these, we will have to do conditioning for better result.
  • Then we will have to calculate the value of dry fabric weight.

Pick%  = (polyethylene+ fabric weight) – polyethylene weight

=Wet fabric weight – dry fabric weigh

= result/ dry fabric weight * 100%

But we will have to ensure that every side can absorb equal amount of chemical.

The amount of times which are fabrics take in passing the desizing chamber can be calculate as-

By dissolving test:Here 1’’ grey cloth with square cross section (□) will have to take in a 500ml pot. Then we will have to take the times which the fabric  takes to dissolve in this solution.

Clip test: Here a clip is used to measure the times which the fabrics take in desizing chamber. In this process  we will have to pass the clip from pressing roller to padder  cylinder and have ti calculate the passing time of clip by stop watch.

Problem of Singeing Machine and Desizing Machine

During operation there are several problem occurred such as:

  • Sometime fire comes out unevenly due to breaking of burner surface. This can make uneven singeing.
  • Problem in bearing of roller. This is the most common problem.
  • High temperature in singeing machine section that occurred when even cold water is not flowed. When temperature is so high machine stopped automatically.
Dr. Joshep, DGM, Textile Division, Seotex Limited, USA
How Cold Pad Batch Dyeing Machine Works?

How Cold Pad Batch Dyeing Machine Works?

Cold Pad Batch Dyeing Machine

Cold pad batch dyeing machine is the easiest process of woven fabric dyeing. In cold pad batch dyeing machine both dye & chemicals are added in the same bath. The ratio of dye & chemical is 2:1. If 1000 liter liquor is to be prepared then 100% will be dye & 50% will be chemical. After mercerizing batcher is feed into the inlet of CPB machine. Where the fabric is passed over some free roller & guider. Here there is a compensator to control fabric open width entry & controlling fabric speed.

Application of Pad Machine

  • Flexible dyeing of short slots.
  • Even coloration.
  • Maximum dyestuff yield.
  • Fast slot &color change.
  • Minimum rest liquor.
  • Reproducibility of shade.

Sketch Diagram of Cold Pad Batch Dyeing Machine

Sketch Diagram of Cold Pad Batch Dyeing Machine
Sketch Diagram

Process Description with Pad Machine

Chemical Tank: Both chemical & color is prepared in different tank according to required. For example we need 1000 liter liquor then we will prepare 100% dye solution & 50% chemical. Then both of them are mixed & agitated in storage tank from which it is feed in to padding bath.

A typical recipe for 128×56/16×10 twill:

  1. Nova Yellow NP – 10.5 gm/lt
  2. Nova Blue CR – 5.00 gm/lt

iii. Nova Red CD – 2.00 gm/lt

  1. Soda Ash -15 gm/lt
  2. Caustic -5 gm/lt
  3. Albaflow pad (wetting)-2 gm/lt

Padding Unit: Here chemical comes from storage tank to maintain even range on padding tank. Here three bowl padding is occurred. Padding pressure is predetermined according to pick up required & fabric speed.

Process Description with Pad Machine
Pad Unit

Batching: After padding fabric is directly rolled in to batcher& packed with poly bag. Then it goes for rotation of 8 – 12 hours for color fixing.

Pad Machine - Batching
Batching

Washing: Finally the fabric washing, soaping, neutralizing & drying is occurred.

Testing required during Cold pad batch operation

  • Pick up testing,
  • Shade matching.

Pick up testing:Before going to Pad steam pick up of the fabric should be calculated & based on this result liquor is prepared.

Shade matching: After each 1000 meter sample is cut then it is packed with poly bag.

Then it goes to carbolite for drying. After that wash & soaping is done. Finally drying then shade is checked in light box.

Solution of Dyeing Fault

Different types of fault can arise during dyeing which can be solved by the following process:

  1. Tropping
  2. Stripping

Tropping: In dyeing process firstly the color is matched in lab in it comes to production.

During production at first a sample is run. If it match then goes for production. But still few problems arise after few meters due to uneven picking shade is varied from original one. It becomes lighter or darker. Some times more reddish or greenish. This type of problem is solved by tropping.If the shade is lighter then addition is done & darker dilution can be done. But during tropping the ratio of dye & chemical is 1:4. A typical Recipe of tropping:

128×56/16×10 twill fabrics dyed in CPB. 15% light.

  1. Nova yellow NP:0.5 gm/lt
  2. Nova red CP: 0.5 gm/lt

iii. Soda Ash -15 gm/lt

  1. Caustic -5 gm/lt
  2. Albaflow pad (wetting)-2 gm/lt

Stripping: If the shade is widely varied from the original one then the fabric goes through stripping. It is the process by which the color of dyed fabric is removed & makes it white for redyeing. The fabric strength become lower for that additional hard finish is required. Another problem is a stripe fabric can only dyed in dark shade, light shade is not possible.

Typical recipe of stripping: 128×56/16×10 twill reactive dyed

  1. Caustic: 20 gm/lt
  2. Hydrise:30 gm/lt

This recipe is not constant. It varies continuously based on color & quality of stripe required.

Cold pad batch (CPB):

Chemical and condition-

Chemical Composition
DyeAs per requirement
Urea50 g/l when dye is with in 15 g/l

 

100 g/l when dye is above in 15 g/l

Caustic 30° Be´ strength(4-14) ml/L according to dye quantity
Soda ash10 g/l when dye is with in 15 g/l

 

20 g/l when dye is above in 15 g/

Wetting agent2 g/l (used when absorbency of fabric is poor)

Chemical and condition (for two bath method):

Chemical for poly partComposition
DyeAs per requirement
Ant migrating agent10 g/l
Acetic acid0.5 g/l
Dispersing agent(3-5) g/l

Thermal condition for poly part:

Drying temperature –      140 °C for 2 min

Curing temperature-        150 °C for 1 min

Chemical for cotton partComposition
DyeAs per requirement
Anti migrating agent10 g/l
Urea50 g/l (for light shade)

 

100 g/l (for dark shade)

Soda ash(10-15) g/l
Lyoprint RG2 g/l
Wetting agent1 g/l (when absorbency is poor)

Thermal condition for poly part:

Drying temperature –      (120/130) °C for 2 min

Curing temperature-        (150/160) °C for 1 min

Chemical and condition for one bath method:

Chemical Composition
DyeAs per requirement
Borax3 g/l
Lyoprint RG3 g/l
Dispersing agent3 g/l
Leveling agent1 g/l
Anti migrating agent10 g/l
Urea50 g/l
Sodium bicarbonate (NaHCO3)10 g/l

Thermal condition for poly part:

Drying temperature –      120 °C for 2 min

Curing temperature-        210 °C for 1 min

Grey Inspection

Here grey fabrics are inspected according to “four point System”

The 4 point system is done according to American Apparel Manufacturer Association (AAMA). This system is used for determining the fabric quality and fabrics defects are assigned based on point’s values.

It helps to find out the number of defects point in 100 Sq. yds.

Faults / Size of defects                              

  1. 3 inches or less 1 point
  2. Over 3’’ but not over 6’’ 2 point
  3. Over 6’’ but not over 9’’ 3 point
  4. Over 9 inches 4 point

In 4 point system

Total points × 36″ ×   100

Points per 100sq. yds =    ——————————————————–

Fabric width in inches * Fabric length in inches

But less than 40 points per 100sq. yds are acceptable level.

Grey fabric Faults:

Name of faultsCauses
1. Starting MarkIt is also called stop mark and happened due to hurt of shuttle in warp and weft and disconnect of electricity.
2. Miss PickIt is happened due to incorrect Sequence of weft insertions.
3. Double PickIt causes due to insertion of two picks in a shed during where only one is intended and appear as a line across the width of fabrics.
4. Loss yarnIt caused for low tension.
5. SlubsIt is happened for abnormally thick place in a yarn.
6. Yarn ContaminationYarn contamination is occurred for mixing of other yarn with the standard unexpectedly.
7. Defective SelvedgeIt is caused for bad selvedge and strength loss.
8. Oil SpotCaused due to grease oil etc.
9. Black SpotIt is occurred due to dirty environment of working.
10. Fungus SpotIt is caused due to contamination of fungus.
11. Size StainedResult of improper sizing.
12. ShaddingTransverse defects causes by structural distortion.
13. MendingIt is happened due to lack of skilled manual needle  work operation and  faults of checking process.
14. Float/Zahala/Hold/TearIt is the result of some interference with the opening of the shed and local incorrect interlacing of warp and weft threads in woven fabrics.

Specification of Cold Pad Batch Dyeing Machine

Speed: 20 m/min

Temperature :- 1) For Reactive – 50-60’C, 2) For Disperse – 80’C

Dye padding: – 50% Chemical, 100% Dyes

Recipe: 1) Dyes, 2) Caustic soda,3) Soda ash, 4) Urea

  1. Dyeing with silicate:
  1. Na Silicate (38 Baume) 50 gm/lt 50 gm/lt   50 gm/lt
  2. Caustic (36 Baume) 15 gm/lt 20 gm/lt   30 gm/lt

iii. Albaflow pad (wetting)     2 gm/lt    2 gm/lt     2 gm/lt

  1. Dyeing without Silicate:
  2. Soda Ash 15 gm/lt
  3. Caustic 5 gm/lt

iii. Albaflow pad (wetting) 2 gm/lt

Dyestuff requirement: That will depend on shade required.

Flow chart of Cold Pad Batch Dyeing Machine:

Fabric inlet

Dye padding

Batching

Rotating (8-12) hr

Washing

Cold Pad dry chemical pad steam (PD CPS) process

The following process is followed-

  • Dyes and auxiliaries based on the base recipe are weighted using a balance or with an electronic pipette.
  • Weighted dyes are mixed with 500 ml of water and stirred for 2 min.
  • According to the quality of the fabric padded Mathis is adjusted (usually 60% pick up). Than the sample fabric is set in the machine and dye liquor is poured in for padding.
  • The padded sample is put on a frame and than in the Mathis drying and curing machine and then set time and temperature. The sample is dried and takes from the frame.
  • The dried fabric is put on the padded machine with chemical pad solution for padding again.
  • The padded fabric is then steamed in the Mathis steaming machine at 120 °C with standard steam for 1 min.
  • Next the sample is washed based on the washing condition.
  • Than the sample is dried using an iron.
  • It is than set in the light box and inspected for color matching.
  • If the color match with the customer sample than the trial ends and the sample is developed; if not then the recipe id adjusted and trial is continues following the same process until a sample match happens.
  • Trial information is noted and each trial sample is attached on the lap dip worksite.

Washing condition:

Cold wash for 1 min

Hot wash with detergent at 90 °C for 1 min

Hot ringing

Cold ringing

Cold pad batch (CPB):

The following process are followed-

  • Dyes and auxiliaries based on the base recipe are weighted using a balance or with an electronic pipette.
  • Weighted dyes are mixed with 500 ml of water and stirred for 2 min.
  • According to the quality of the fabric padder Mathis is adjusted (usually 60% pick up). Than the sample fabric is set in the machine and dye liquor is poured in for padding.
  • The next step is for fix the color. Padded sample is put in polythene bag for 5 min. Than a sample piece of that fabric is cut from the sample for rapid fixation test by microwave woven. The sample is hanged on a glass rod over the vassal containing about 50 ml of water and covering the sample and the vassal with a lid. At power of 2 setting. The sample is steamed for 6 min.
  • For the color fixation there are two methods. In one method the padded fabric wrapped for 8 hr with polythene bag. In the other method which is rapid process, microwave woven is used. Here the dyeing piece should be kept in the microwave woven (power of 2) in plastic vassals with 50 ml of water for 6 min.
  • Next the sample is washed based on the washing condition.
  • Than the sample is dried using an iron.
  • It is than set in the light box and inspected for color matching.
  • If the color match with the customer sample than the trial ends and the sample is developed; if not then the recipe id adjusted and trial is continues following the same process until a sample match happens.

Washing condition:

Cold wash for 1 min

Hot wash with detergent at 90 °C for 1 min

Hot ringing

Cold pad batch dyeing ringing

Dr. Wiliam, Lecturer, USA