comfort mill report on yarn dyeing

COMFORT MILL REPORT_____________________________________________________________________________________________ PRESTON UNIVERSITY

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COMFORT KNITWEAR & SURGICAL COTTON

DYEING UNIT

PRESTON UNIVERSITY

INTERNSHIP REPORT

Submitted To: Mr. AHMAD SALEEM Processing manager

Submitted By:

NAME Registration No

AAMIR SHABBIR 1617-304003

SALMAN MANZOOR 1617-304009


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Contents

________________________________________________

1. INTRODUCTION �� Acknowledgments…………………………………………….3

�� COMFORT Mill……………………………...……………….4

�� Flow chart………………………………………………….….5

�� Cotton……………………………………………………...….6

�� Polyester………………………………………………….….10

2. Winding Section……………………………………….………………….14 3. Chemical Store Room……………………………….………...………….17

4. Testing Lab………………………………….…………………………….19

i. Types of Dyes ……………………………..…………….12

ii. Direct Dye………………………………………….…….22

iii. Reactive dye……………………………………..……….25

iv. Dipping test………………………………………...…….31

v. Bleeding Test…………………………………………….33

vi. Ph test…………………………………………………….33

vii. Color matching test………………………...…………….34

viii. Quality test……………………………………………….34

ix. Oscillator Box…………………………………...……….35

x. Light Box………………………………………………...37

5. Production hall………………………………….………………………...38

i. Vertical dyeing machine…………………….….………….38

ii. Main parts of vertical dyeing machine………….…………40

iii. Recipe of yarn dyeing……………………………………..42

iv. Hydroextractor…………………………………………….45

v. Dryer…………………………………………….……...….45

vi. Dyeing Methods……………………………….……….….46

vii. Types of Dyeing……………………………………….….47

6. Store Room………………………………………….………………....….51


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ACKNOWLEDGEMENT

The accompl ishment of th is task depends on the cont r ibut ion of

many people wi thout whom I could not do any th ing .

Fi rs t of a l l , I would l ike to thanks Al lah Almighty wi thout

whom I would not be able to complete and manage th is pro ject .

Secondly, I am thankful to

Mr. AHMAD SALEEM (p rocess ing manager ) who have up t i l l

now provided me wi th the s t andards o f excel lence . He has been

a lways encouraging us and h is apprecia t ion has g iven us new

zeal and dedicat ion towards complet ing our pro ject wi th more

mot ivated ef for ts .

Final ly , but more speci f ica l ly I want to thanks

MR. MISBAH-u-DIN

MR. M.ASIF

MR. ALI

Without whom we would not be able to complete my p ro ject

e f fect ively .


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MILL INTRODUCTION

Mills Name COMFORT KNITWEAR & SURGICAL COTTON DYEING UNIT Processing

manager MR. AHMAD SALEEM

Phone 042-5270184

Address 22 km off ferozepur road, LAHORE

Fax 92-425274146

Email [email protected]

City LAHORE

State PUNJAB

Country PAKISTAN

Zip 54770

URL www.ckl.com.pk


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FLOW CHART

Raw Material Winding Section Chemical store room Testing Lab Production hall

Cotton yarn

Polyester yarn

Cone to Bobbin

Bobbin to cone

Colour matching test

Bleeding test

Ph test

Dipping test

Quality test

Store room

Yarn + cotton dyeing

Hydroextractor

Dryer


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Cotton

Introduction

Is a vegetable fibre obtained from the mature capsule of the cotton plant, a shrub about 40 cm high, with leaves and flowers of a red or yellow colour. When the flower is fecundated it loses its petals and within 25 days a capsule surrounded by a leaf called bract grows. The capsule is sustained by a cup and has a drop shape rounded at the lower extremity. Inside the capsule there are from five to eight seeds on which the fibre developed. When the capsule is mature it opens into four parts showing the cotton ball. On the same plant the maturation of the capsules does not occur simultaneously, therefore more passages are required for the harvest of the cotton. The harvest is carried out a week after maturation. The first operation after harvesting is husking, which permits the removal of the fibres from the seeds. Then the cotton is carded and combed so as to eliminate all the impurities. 4000 fibers is the seed average. Staple length = 1/8" - 2.5" (0.32 - 6.35cm) - for manufacturing yarns, fabrics, 7/8" - 11/4" (2.22 - 3.18cm) is standard.

Cotton Burns readily and give acrid smell 8.5% 1-2 inch (22-50 mm) 18-1.5 micron

0,5-10 g 4-13%

8. Unaffected by the dilute acid solution upto 70F. Above this temperature or if acid is dried, cotton is tendered. It means losses the tensile strength. Concentrated mineral acids gradually swell and dispersed. 9. Unaffected by boiling in dilute caustic soda.

10. Insoluble in hydrocarbons. It means benzene, xylene,

toluene etc.

11. Insoluble in alcohol, ether, acetone etc.

12. Attack by acid or alkahne hydrochloride (CaoCI2), NaoCI2 and

other powerful oxidizing agents.

13. It does not melt but decompose.

14. Characteristic scale structure on surface gives a positive

reaction to test for Suiphure.

1. Name 2. Ignition 3. Moisture Regain 4. Fiber Length 5. Diameter 6. Breaking Strength 7. Elongation at Break


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15. Solution + PbAg2 -> Pbs

To the solution of wool and lead acetate, a black coloration or precipitated

would appear.

16. It is rapidly dissolved in Cupra Ammonium solution.

Cotton production

Cellulose chemical structure

THE ACTION OF ACIDS ON COTTON -

Boiling with dilute acids will ultimately hydrolyze the cellulose to glucose. Milder action by acids at lower temperature gives rise to tendering with the formation of hydro cellulose. Cold concentrated acids like sulphuric acid dissolve the cellulose with the formation of cellulose hydrate. If this solution is poured into cold water the cellulose hydrate is precipitated in a gelatinous form. This reaction is used in the manufacturing of" parchment paper".

Prevention of the tendering effect of acid can only be achieved by its complete removal. For this purpose, Neutralization with sodium carbonate followed by shorter rinsing is often to be preferred.


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THE ACTION OF ALKALIS ON COTTON

Mild alkalis such as sodium carbonate have no action on cotton neither at low temperature nor at high temperature in the absence of air. In the presence of oxygen, however, oxy-cellulose is produced gradual y with consequent tendering. Dilute solutions of strong alkalis such as sodium hydroxide act in very much.

In the complete absence of air, cotton can be boiled with 2% sodium hydroxide with out least tendering. If oxygen is present, however, oxy-cellulose will soon make its appearance. This can be demonstrated experimentally by boiling cotton, yarn with 2% NaoH to which a little Mgcl2 has been added to act as oxygen carrier. If a steam of air were drawn through the boiling liquor, the yarn will become extremely tendered in a very short tine. Reaction of cotton ( modified cotton)

1. SODIUM CELLULOSE FORMATION

R--CELLULOSE--OH + NaOH ----------� R—CELLULOSE—O—Na + H2O

( sodium cellulose)

2. CELLULOSE NITRATE FORMATION

R-- CELLULOSE—OH + HNO3 -----------� R--CELLULOSE—O—NO2 +H20 (CELLULOSE NITRATE)

3. CARBOXY METHYL CELLULOSE FORMATION (CMC)

R-- CELLULOSE—OH + Cl--CH2COO—Na---� R-- CELLULOSE—O—ClCHCOO+ NaCl+ H2O It is gum used as a thickening agent. It is prepared by sodium choloro acetic acid.

4. CELLULOSE ACETATE FORMATION

R-- CELLULOSE—OH + CH3COOH -� R-- CELLULOSE—O—CH3COO + H2O CELLULOSE ACETATE


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5. XANTHATE FORMATION

It is a process of regeneration of cotton. R-- CELLULOSE—ONa + CS2 -----� R-- CELLULOSE—O--- (CS)SNa (XANTHATE)

H/H2O

R-- CELLULOSE—O—(CS)SNa ---------� R—CELL—OH + CS2 + Na ACID

6. REACTION WITH OXIDIZING AGENT

[O] [O] R-- CELLULOSE—OH-----� R-- CELLULOSE—CHO---� R-- CELLULOSE—COOH (ALDEHYDE) (Carboxylic acid derivative)

Grading of cotton quality

• length

• uniformity

• diameter • strength

• maturity

• colour

Yarn count

For export purposes comfort yarn dyeing unit use different counts of cotton yarn. i.e.

10, 12,17,18,20,21,24,26,28,30,40,50


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Polyester (PET)

Introduction

POLYESTER FIBERS

Polyester fiber is a " manufactured fiber in which the fiber forming substance is any long chain synthetic polymer composed at least 85% by weight of an ester of a dihydric alcohol (HOROH) and terephthalic acid (p-HOOC-C6H4COOH)" [3]. The most widely used polyester fiber is made from the linear polymer poly (ethylene terephtalate), and this polyester class is generally referred to simply as PET. High strength, high modulus, low _shrinkage, heat set stability, light fastness and chemical resistance account for the great versatility of PET.

POLYMER FORMATION

Polyethylene Teraphthalate (PET) is a condensation polymer and is industrially produced by either terephthalic acid or dimethyl terephthalate with ethylene glycol. [26] Other polyester fibers of interest to the nonwovens field include:

(a) Terephthalic Acid (PTA), produced directly from p-xylene with bromide-controlled oxidation.

(b) Dimethyl Terephthalate (DMT), made in the early stages by esterification of terephthalic acid. However, a different process involving two oxidation and esterification stages now accounts for most DMT.

(c) Ethylene Glycol (EG) initially generated as an intermediate product by oxidation of ethylene. Further ethylene glycol is obtained by reaction of ethylene oxide with water.


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POLYMERISATION

The Terepthalic acid and Ethylene glycol are taken into the autoclave. In the autoclave, the air is sucked out and Nitrogen gas is injected into it. Then polymerization is done at a temperature of 270c° and the pressure is generally atmospheric pressure 1-e 760mm- of Hg. Here in the autoclave cobalt salt l-e cobalt phosphate [CO3(PO^)] and compound of Antimony ( Sb ) or Germanium ( Ge ). are used as a catalyst. The polymer is extruded in form of a ribbions form from the autoclave. The ribbons are cut into chips. These chips are dried to remove any residual moisture.

MELT SPINNING

The dried chips are fed into the hopper and are melting because the walls of the hopper are electrically heated. Then the help of metric pump takes it to the spinnert. As the filaments come out from the holes of the spinnert, They instantly solidify. These filaments are taken for stretching. Normally they are stretched 5-10 time's forms here it is taken to the ring spinning frame where the yarn is wound on the bobbins as they are taken to the crimps if we have prepared Tows the crimpers produced after spinning . Tows are prepared according to the desire length by a cutter.


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POLYESTER FIBER FLOW CHART

DYEING PROPERTIES

Because of its rigid structure, well-developed crystallinity and lack of reactive dye sites, PET absorbs very little dye in conventional dye systems. This is particularly true for the highly crystalline (highly drawn), high tenacity-high modulus fibers. Polyester fibers are therefore dyed almost exclusively with disperse dyes.

A considerable amount of research work has been done to improve the dye ability of PET fibers. Polymerizing a third monomer, such as dimethyl ester, has successfully produced a cationic dye able polyester fiber into the macro-molecular chain. This third monomer has introduced functional groups as the sites to which the cationic dyes can be attached [8]. The third monomer also contributes to disturbing the regularity of PET polymer chains, so as to make the structure of cationic dye able polyester less compact than that of normal PET fibers. The disturbed structure is good for the penetration of dyes into the fiber. The disadvantage of adding a third monomer is the decrease of the tensile strength.

A new dyeing process for polyester fiber at low temperature (40(C and below) has been reported [9]. This method employs a disperse dye in a microemulsion of a small proportion of alkyl halogen and phosphoglyceride. The main advantage of this method is low temperature processing, but there remains the environmental problem that is produced by using toxic carriers.

Another approach has been introduced by Saus et al [20]. The textile industry uses large amounts of water in dyeing processes emitting organic compounds into the environment. Due to this problem a dying process for polyester fiber was developed, in which supercritical CO2 is used as a transfer medium [21]. This gives an option


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avoiding water discharge. It is low in cost, non-toxic, non-flammable and recyclable. When dyed in an aqueous medium, reduction clearing is to be carried out to stabilize color intensity, which produces more wastewater. Reduction clearing is not carried out following supercritical dyeing. Other advantages are better control of the dying process and better quality of application achieved.

Spun bond PET nonwoven webs have been treated by (SO2+O2) plasma and (N2+H2+He) plasma at the University of Tennessee, Knoxville. The research results show that spun bond PET nonwovens web can be colored by conventional water-soluble acid dyes [10]. Plasma techniques open new avenues for coloring PET fabrics and are sure to be more evident in the coloring of polyester fibers in the future.

General Polyester Fiber Characteristics:

• Strong

• Resistant to stretching and shrinking

• Resistant to most chemicals

• Quick drying

• Crisp and resilient

• Wrinkle resistant

• Mildew resistant

• Abrasion resistant

• Retains heat-set pleats and crease

• Easily washed

Properties

Specific weight 1,22 to 1,38 g/cm3

Tenacity up to 85 cN / tex

Moisture regain 0,2 - 0,5 %

Effects to heat ironing temperature 150 - 200° C melts at 249 - 288° C


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WINDING SECTION Incharge M. iqbal

No. of Machines 9 company Groove drum winder

labour 18

shift 2 ( 12 hours each)

Function of winding � Creeling

Placement of full packages in position to unknown also removal of empty packages and replacing them with full ones.

� Piecing up

Finding and connecting two ends of packages piecing up can be done by knotting or splicing. The piecing up is carried out when end breaks or the creeling operation is complete.

� Doffing

It is the removal of full cones and there replacement with the empty ones.

Main parts of this machine

1) Feeler 2) Yarn clearer 3) Yarn guide 4) Tensioning device

1. Feeler

It activate when end breaks or case of supply bobbins becomes empty.

2. Yarn clearer

Yarn clearer could be of mechanical, electrical nature and are used to remove yarn imperfections. i.e. slubs, thick and thin places.

3. Yarn guide

It is use to control the yarn path.


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4. Tensioning device

These are used to give the winding yarn a proper tension for the firmness of the cones or packages. The tensioning devices easily adjustable. The tension to the winding yarn is adjusted according to the yarn strength as too high tension damages the yarn as produces hairiness. Similarly using to low tension will result in an unstable yarn packages which will be difficult to unwind.

MODEL GA014(MD.PD) GROOVED DRUM WINDER

APPLICATIONS

Model GAY014 grooved drum winder is divided into two types: MD and PD, both are suitable for winding of cotton, flax, wool and synthetic fibre which is supply bobbin for warping and Knitting. The structure of the machine is in a novel style and the electric controlling components are high quality. This machine has attractive appearance, runs stably. The bobbin forming is superlative, drum winder. This machine can be connected with several attachments. These are suitable for the customer’s different demand.


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MAIN SPECIFICATIONS

1 Spindle pitch 254mm

2 Number of spindle 40、60、80、100、120

3 Traverse 152mm Model MD 510-700

4 Winding

speed(meter/minute) Model PD 140-160

5 Drum specification Outer diameterφ82.5mm, two and half cycles 6 Stop device One set per spindle, scts at independently

7 Yarn cleaning

device One set per spindle

8 Forming size Big end φ200×152mm Wooden

tube 5°57’Ø25 X Ø62 X 177

9 Bobbin size Paper tube 5°57’、 9° 15’

Model MD Ring bobbin or twist cop 10 Yarn Supply

Model PD Hank yarn, reel perimeter 1371.6mm

11 Dimension(mm)

Spindle number

40 60 80 100 120

Length 5951 Model

MD Ring bobbin or twist cop

10 Yarn

Supply Model PD

Hank yarn, reel perimeter 1371.6mm

11 Dimens 8491 11031 13571 16111

Width 1400 Model MD 1525

Height Model PD 2000

Spindle number

40 60 80 100 120

Model MD 2.19 2.79 3.61 4.5 5.26 12 Weight (ton)

Model PD 2.23 2.86 3.72 4.6 5.37

Model MD 2 main motors 2.2kw, 1 auxiary motor

0.37kw 13 Motor

Model PD 2 main motors 1.5kw, 1 auxiary motor

0.37kw

Ribbon breaking control

Adjustable range of intermittence rate: 20 to 40 times/min

14 Electric Control Box

Cleaning device control system


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CHEMICAL STORE ROOM

Incharge MR. AAMIR KHAN

Labour 5

Shift 2 (12 hours)

Maintenance of Chemicals

• Perform regular inventory inspections of chemicals.

• Update the chemical inventory at least annually, or as requested by the administration.

• Do not store food and drink with any chemicals. • If possible, keep all chemicals in their original containers.

• Make sure all chemicals and reagents are labeled.

• Do not store chemicals on the lab bench, on the floor, or in the laboratory chemical hood.

• Ensure chemicals not in use are stored in a locked facility with limited access. • Know the storage, handling, and disposal requirements for each chemical used.

• Make certain chemicals are disposed of properly. Consult the label and the Material Safety Data Sheet for disposal information and always follow

• Appropriate chemical disposal regulations.

Chemicals Chemicals are stored in chemical store room i.e.

� Wetting agent � Stabilizer � Caustic soda � Soda ash � Hydrogen per oxide � Detergent � Formic acid � Acetic acid � Sulphuric acid � Killer � Fixer � Leveler � and dyes


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Dyes Synazol dyes are use for yarn dyeing.

DYES SHADE

Yellow Tones

4GL Yellow, Lemmon

4GR semi gold 2 GR golden

Red Tones

Red GD Pinkish dull tone Red 6BN Blue tone

Blue Tones

Blue BRN dull blue

Blue R special (bright shade)

Green Tones

Turquoise (green and blue)

Navy KBF


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TESTING LAB

Incharge MR. M. Asif

Labour 4

shift 3 (8 hours)

lab instruction .

� Check the label to verify it is the correct substance before using it.

� Wear appropriate chemical resistant gloves before handling chemicals. Gloves

are not universally protective against all chemicals.

� Before experiment wash the beaker with water.

� Never use defective equipment.

� Never permit smoking, food, beverages, or gum in the laboratory.

� Never run in the laboratory

� Hold containers away from the body when transferring a chemical or solution

from one container to another.

� Turn off all heating apparatus, light box and oscillator box when not in use.

� Wash hands after removing gloves, and before leaving the laboratory.

Types of dye

Acid dye - In this process, water-soluble anionic dyes are applied to fibers from neutral to acid dye bath. Usually fibers of silk, wool, nylon and modified acrylic are dyed.


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Basic dye - Water soluble cationic dyes are applied mainly to acrylic, wool and silk fibers. Direct (substantive) dye - This process uses either sodium chloride or sodium sulphate in neutral or little alkaline dye bath. Usually cotton, paper, leather, wool, silk and nylon are dyed.

Mordent dye - The process requires the use of mordent (a dyeing substance) to improve the fastness of the dye on the fiber like water, light and perspiration fastness.

Vat dye - This dye is insoluble in water and does not dye fiber directly. Reduction in alkaline liquor gives the water soluble alkali metal salt of the dye. This form dyes the textile fiber.

NHCOC6H5

NHCOC6H

(Vat Red)


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Reactive dye - This dye contains a reactive group, haloheterocycle or activated double bond. It is applied to the fiber in a weakly alkaline dye bath, which forms a chemical bond with a hydroxyl group on the cellulosic fiber.

Disperse dye - A substantially water insoluble, developed for dyeing cellulose acetate. The dyes are ground finely in the presence of a dispersing agent. It is in the form of paste, spray dried, or powders. It is used to dye nylon, triacetate, polyester and acrylic fibers.

Azoic dye - An insoluble azo dye is produced directly onto or within the fiber in this process. This is achieved by the treatment with a diazo component and a coupling component.

Sulphur Dyes- these are water insoluble dyes. There for before there applications these dyes are made soluble. There for these dyes are reduced by sodium sulphur to water soluble products that are substantive to cotton and from which insoluble dye is regenerated by air or chemical oxidation.


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CHART OF DYES V/S FIBERS.

DYE \ FIBRE Cotton Wool Silk Polyester Acrylic Nylon Vinyl

Acid Dyes

Basic Dyes

Direct Dyes

Mordant Dyes

Reactive Dyes

Vat Dyes

Azoic Dyes

Disperse Dyes

Sulphur Dyes

In comfort yarn dyeing testing lab these dyes are used

� Direct Dye � Reactive Dye

Direct Dyeing Application

The first direct dye was called Congo red and was introduced in 1884. It was called a direct dye because it was the first dye to become available for coloring cellulose 'directly', without the use of a mordant. Direct dyes are applied in a boiling dye bath in the presence of salt.

PROPERTIES

� It is soluble in water � It is application through only exhaust process. � It is applied through the affinity of the electron of dye and fabric

Advantages: · Cheap · Simple to apply · Wide range of colors · Very good fastness to light

Disadvantages: · Poor wet fastness · Moderate brightness


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After treatment of direct dyes

1. Diazotization and development

Many long establish direct dyes containing primary amino group could be diazotize and coupled on the fiber by variety of developers including nephthol, diamines and phenols.

N N+

Phenol +

( diazonium ion)couple

2. Metal salts treatment

In this process direct dyes are treated with acidified copper solution.

Recipe CuSO4 --------------------- 0.25 —2 % H2SO4 -------------------- 1 % Time ------------------------ 20-30 mint Temperature -------------- 60c It improve the light fastness of direct dye

3. Cationic fixing agent

These compounds interact with sulphonate groups in direct dye and increase the wet fastness of direct dyed fabric. Heat stable ability 60c.

4. Formaldehyde treatment

H---C---H ll O


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Treatments of certain direct dye mainly black with 2-3 % formaldehyde (30%) and 1% acetic acid (30%) for 30 mints at 70c to 80c Improve the wet fastness of the dye.

5. Cross linking agent and resin treatment

It also improves the wet fastness properties by treating cellulose with amide formaldehyde resins. Resins are cross linking agent.

Chemical Structures Of Direct Dye


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Reactive Dyeing Developed in the 1950s, these were the first dyes produced capable of reacting chemically with the fiber (usually cellulose) under alkaline conditions. The dye thereby becomes part of the fibers, rather than merely remaining as an independent chemical entity within the fiber. Reactive dyes are applied at relatively low temperatures, with controlled amounts of salt and alkali.

Definition:-

A fiber-reactive dye will form a covalent bond with the appropriate textile functionality. This is of great interest, since, once attached, they are very difficult to remove.

PROPERTIES

� It is soluble in water � It is application through only exhaust process. � It is apply by the ionic bonding between the dye and the fabic

� Advantages: · Simple to apply · Wide range of bright colors · Good fastness to light and washing

� Disadvantage: · Relatively expensive

Classes of reactive dyes:

1. Cold brand dyes (low quality)

Dichloro triazine

Dyeing temp: Room temperature

Dyes example:

Reactive red M5B

Reactive blue MR, yellow CR


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2. Hot brand dyes: (high quality)

Mono chlorotriazine

80-85’c

Dyes example: Reactive yellow HER

Reactive red H8B

3. Medium temperature dyes :( medium quality)

Vinyl sulphate 60’c

Dyes ex: Ramozal black b

Ramozal blue r

Reactive colours:

Light colors – 1 % depth

Medium colors = 100:1 kg of dye

Dark colors - 3 % = 100:3

Types of reactive dye colors:

1. Cold brand - 40’c

2. Medium hot - 60’c

3. Hot - 85’c


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Classification of reactive dye

a) Alkali controllable reactive dyes

These dyes are lightly reactive. Fixation of these dyes is carried out 40-60c. They have low exhaustion rate in natural salt solution before adding the alkali. The addition of alkali should be portion wise or controlled.

b) Salt controllable reactive dyes. (NaCl)

These dyes have low reactivity fixation at 80c. The exhaustion rate is high at natural ph. So it is important to add salt carefully in order to achive level dyeing. The addition of salt should be portion wise or controlled.

c) Temperature controllable reactive dyes.

These dyes react with cellulose at temperatures above the boil in the absence of alkali can be applied under the same condition as the salt controllable dyes these dyes have self leveling property so there is no need to ass any auxiliary in order to achieve level dyeing.

Handling and packaging of reactive dyes.

The reactive dyes should be stored in cool dry condition and lid of packages must be firmly replaced after use.

Factors In Selecting Dyes

• Economy

• Shade (brightness or dullness)

• Fastness Requirements • Level Dyeing Properties

• Ease of Dispersion Dissolving

• Dusting

• Environmental Concerns • Bonding stability


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Lab tests

1. Dipping test 2. Bleeding test 3. Ph test 4. Color matching test 5. Quality test

1. Dipping Test

HS Hub Salt 60 g/l

= ---------- = --------------- = -----------

SA Soda Ash 20 g/l

Hub salt for 5 g sample

(Weight of sample) x (weight of salt) x (liquor ratio)

= -------------------------------------------------------------

1000

(5g) x (60 g/l) x (10)

= ------------------------------

1000

= 3 g

Soda ash for 5 g sample

(Weight of sample) x (weight of soda ash) x (liquor ratio)

= -------------------------------------------------------------

1000

(5g) x (20 g/l) x (10)

= ------------------------------

1000

= 1 g


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Synthetic yellow 2GR 1.3

Synthetic Red GD 0.284

Synthetic Blue BrN 0.103

W= weight of sample = 5 g

P= dye percentage

C= concentration of dye solution. = 0.5

W x P

= ------------

C

5 x 1.3

= --------------

0.5

= 13 ml

Synthetic yellow 2GR 13 ml

W x P

= ------------

C

5 x 0.284

= --------------

0.5

= 2.84 ml

Synthetic Red GD 2.84 ml

W x P

= ------------

C

5 x 0.103

= --------------

0.5


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= 1.03 ml

Synthetic Blue BrN 1.03 ml

Dye Recipe

Synthetic yellow 2GR

13 ml Synthetic Red GD 2.84 ml Synthetic Blue BrN 1.03 ml

Temperature 60 c

Soda ash 1 hours

Neutral with formic acid

0.8 ml with 5g %

Soaping

washing

2. Bleeding Test

Recipe

Water 125 ml Soda ash 0.25 g detergent 10ml of 5 % sol. Wet yarn 5 g Dry yarn 1 g Dry yarn 1 g

Temperature 60 c

time 30 mints.

3. Ph test

� Ph is very important while dyeing yarn or fabric. � Ph should be maintained within the specified limit. � Ph should be ranging from 10.20 to 10.80 � High ph values may damage the yarn. � Ph value is determined by ph meter.


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4. Color matching test

By spectrophotometer The sample form that allows the quickest yet potentially most variable measurement is yarn. The most common method for measuring yarn is to obtain a small skein and simply place it against a small measurement port and rotate the sample for two or three measurements. The repeatability of this particular measurement method is questionable and must be confirmed as mentioned earlier. Individual yarns in the skein must be aligned to prevent the formation of shadows that the instrument would detect as depth of shade. The skein must also be thick enough to prevent light from passing through the strands and reflecting off the background which is typically the sample holder. An important fact to keep in mind is that skeins will produce lighter readings than sleeves knitted from the same yarn and these two materials should not be compared to each other for color difference calculations. Always compare yarn to yarn and sleeve to sleeve. Yarns that are very bulky should be measured behind a glass plate to prevent the yarn from bulging into the spectrophotometer measurement area. Use the instrument’s specular excluded mode to remove the glossy reflectance from the glass surface. Loose pile goods such as carpet and towels can be measured in the same way to prevent the yarns from protruding into the instrument and to prevent fibers from falling into sphere instruments. When matching shades for use in pile goods such as automotive or home upholstery, a skein of yarn is typically pulled through a cardboard tube and cut to allow evaluation of the tips of the yarn instead of the sides. These shades are typically evaluated visually because of the difficulty in presenting a uniform surface to the spectrophotometer for measurement. To successfully measure the color of a yarn pom, the density of the pom at the measurement plane must be controlled to prevent differences in depth of shade due to light trapped in open areas between the yarns. The pom must also be placed at the port in such a way as to prevent flattening of the pom which will expose the sides of the yarn to measurement. This can be very difficult without the use of a custom designed sample presentation apparatus. Other useful techniques for yarn measurement include winding the yarn around a card or tab and using specially designed devices with springs that clamp the yarn securely to a plate. Yarn tension is a concern in either case and must be controlled from sample to sample to prevent measurement errors.

5. Quality test

After all the processes quality test of the yarn is carried out for the final approval of the lot.


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LAB Machines

a) Oscillator box

b) Light box

c) Ph meter

d) Weigh machine

e) Dryer

Oscillator box

This machine is made by RAPID co. Glycerin is use in two bath of oscillator box. Conventional laboratory colouring tests use water baths and mixing the recipes in the beakers to cope with normal working conditions. The disadvantages are uneven stirring by hand labour an extreme working environment due to the hot water bath plus that only 3 to 4 tests are being carried out. Glycerin is used instead of water because the temperature of glycerin is higher then water which avoid the evaporation and ceasing of the machine.

Glycerol, or glycerin, is a clear, colorless, odorless liquid with a thick, syrupy texture. ... Melting Point. 20 ° C. Boiling Point. 290 ° C.

Contents Water Glycerin

Boiling point 100 c 290 c

Melting point 0 c 20 c

The OSCILLATING DYEING MACHINE performs even mixing of the recipes simultaneously and allows more spare time of the operator to increase her efficiency.


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Operating Principle Sketch showing the Operation Principle Because of Oscillation, Leveling result is thus achieve.

General Features

DRIVING Wide-rang infinitely variable speed control at 50-200 oscillation per min.

TEMPERATURE CONTROL By precise automatic controller with indicator.

The temperature of two baths can be control according to the desire.

LIQUOR RATIO Normally 1 to 10 or above.

Working Temperature : 30 oC ~ 97 oC

Main Functions 1. To prepare colouring recipes 2.For colour fixing and various fixing tests 3.Dyeing Tests 4.Auxiliaries Test

� Labours

Operator 1

Sr

No Description

1 Cover

2 Dye receptacle

3 Holder

4 Dye Liquor

5 Material to be Dyed

6 Heating Medium


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Light box (Shade matching lighted box)

Advantages:-

1. Five standard lights confirming to ISO and AATCC (American) standards. & UV, D65, CWF, INCA, TL84. 2. Steel solid body in baked paint confirming to Munsell 7 - standards 3. Standard lighted switches with options to choose any one of the light sources 4. All steel structure, no cardboard or wood used anywhere. No rust, No peeling off problems.

The Multi-Light Color Viewing Booth is an innovative and efficient instrument for color evaluation and color quality control. It features to increasing productivity, cost-saving in production and ease of operation. This system complies with the major international standards include ASTM D1729 and ISO 3664. It is applicable for the industries of textiles, dyes, printing, paints, plastics, inks, etc.

The multiple illuminants are switch able to simulate various lighting condition for detecting metamerism. The Booth includes five illuminants; Daylight D65, Illuminant A , Cool White Fluorescent (CWF), TL84 Warm White Fluorescent, Ultraviolet (UV) with optional light sources; CIE D75, CIE D50, TL83, TL85 and Ultralume 30.

� Labour

Operator 1

D65 Daylight CWF Cool White Fluorescent TL84 Warm White Fluorescent UV Ultraviolet INCA Incandescent "A"


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PRODUCTION HALL

MR. Misbah u Din (Asst. Processing Manager)

VERTICAL DYEING MACHINE

Vertical dyeing machines mod. GDV Suitable for dyeing yarn in packages, loose fiber tops and tows and with suitable material carriers yarn in beams, these machines are built with diameter range from 1400 mm to 1700 mm. The standard production loading range vary between 30 and 2000 Kg. If coupled, with variable loading capacity maintaining the same liquor ratios. Important factors that characterize the vertical dyeing machine are: a - vertical axis of the machine with the necessity of installation on two floors b - necessity of working with a bridge-crane or hoist for the loading/unloading of the material carrier c - bath ratio up to1:3 in the loose fiber case or 1:5 in packages dyeing d - possibility of partial or complete automations with bridge-crane e - external heat exchanger

Other characteristic of the vertical dyeing machines are:

- construction in stainless steel AISI 316 L - low liquor ratio - complete automatic running of the dyeing cycle through microprocessor - automatic control of the Head - automatic device for the control of the differential pressure run by an inverter - liter counter device to optimize the dyeing cycle - dewatering system of yarn to reduce dyeing times, rinsing and drying


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Automatic bridge crane for loading / unloading

Material carrier for packages Material carrier for loose fibers tops/tow

In comfort yarn dyeing unit there are 4 vertical dyeing machines and one testing machine.


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Main parts of the machine

1. Material carrier 2. Tank 3. Mixer 4. Lid 5. Circulating pump 6. Vessel 7. Inverter 8. Sampling device 9. Heating exchange.

Lid

Material Carrier

Mixing Tank

vessel

inverter

Heat Exchanger

Circulating Pump

Sampling Device

1. Material carrier It carries the material i.e. cones or packages which are to be dyes.

2. Chemical tank

All dyes and chemicals are first put in the tank in which mixing of dyes and chemicals take place.


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3. Mixer

Mixer is basically a motor which mix the dyes and chemicals in the chemical tank before their introduction in the machine. 4. Lid

It is used for the opening and closing of the machine.

5. Circulating pump

Circulating pumps which control the circulation of water.

6. Vessel

It is a steel container in which yarn dyeing takes place.

7. Inverter

Automatic device for the control of the differential pressure run by an inverter

8. Sampling device.

For the lab testing samples of yarn are put in the sampling device. so that we prepare a sample without stoppage of machine. Usually 5gram sample is used. 9. Heating exchange.

A device designed to transfer heat between two physically separated fluids; generally consists of a cylindrical shell with longitudinal tubes; one fluid flows on the inside, the other on the outside.

Labour

Operator 1

helper 1


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Recipe of Yarn dyeing (For dark shade)

SHADE = VERY DARK WEIGHT 480

Liquor Ratio = 1:7.5 CYCLE TIME 3.15

DESCRIPTION KGS % AGE g/l WATER H.W Read

S.W Read

HALF BLEACH 3600 4.571 2

LUTEN SOL-TO-06 1.08 0.3

STORE XNP 1.08 0.3

STABICOL A-SOLUTION 0.9 0.25

CAUSTIC SODA (F1) 7.2 2

HYDROGENPEROXIDE 7.2 2

NEUTRAL/HOT WASH 3600 7.143 2

FORMIC ACID 4.32 1.2

KILLER 3600 9.714 2

TINOZYME.CAT 1.26 0.35

LEVELLING 3600 9.714 2

DYEING ( COTTON) 3600 12.286 4.571

SYNAZOL-G YELLOW HF-2GR 3.048 0.685

SYNAZOL RED HF-6BN 6.72 1.4

SYNAZOL NAVY BLUE RH 15.168 3.16

HUB SALT 288 80

SODA ASH 18 5

CAUSTIC SODA (F1) 3.6 1

NEUTRAL/SOAP 3600 14.857 2

FORMIC ACID 2.7 0.75

MULTI WASH A-9500 7.2 2

FIXING 3600 14.857 2

SUREFIX FO FIXER 6 1.25

FINISHING 3600 17.429 2

ACETIC ACID 1.08 0.3

LUSTRAFFIN SA 86 4.08 0.85


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1) HALF BLEACH (95c x 20min)

• Bleaching is done to improve the whiteness of the yarn.

• If shade is dark half bleaching is carried out.

• In case light shade full bleach is carried out.

Wetting Agent

It decreases the surface tension of water and helps the solution to penetrate into the core of fabric.

i. LUTEN SOL-TO-06 ii. STORE XNP

Both chemical are use as wetting agents in comfort yarn dyeing.

iii. Stabicol A- Solution

It is use as a stabilizer to stabilize the nascent hydrogen which is released by hydrogen peroxide. Stabilizers must be added to the bleach solution to control the decomposition of hydrogen peroxide. Stabilizers function by providing buffering action to control the pH a t the optimum level and to complex with trace metals which catalyze the degradation of the fibers. Stabilizers include sodium silicate, organic compounds and phosphates.

iv. Caustic Soda

It is used to increase the rate of reaction.

MAJOR BLEACHING AGENTS

1. SODIUM HYPOCHLORITE 2. HYDROGEN PEROXIDE 3. SODIUM CHLORITE (NaC1O2)

In comfort yarn dyeing department hydrogen peroxide bleaching agent use.

v. Hydrogen Peroxide Hydrogen peroxide was first used to bleach cotton in the 1920's. By 1940, 65 % of all cotton fabrics were bleached with hydrogen peroxide, largely brought about by the invention of the J-box which lead to continuous processing. Today, it is estimated that 90 t o 95 % of all cotton and cotton/synthetic blends are bleached with


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hydrogen peroxide. It is available commercially as 35, 50 and 70 % solutions. It is a corrosive, oxidizing agent which may cause combustion when allowed to dry out on oxidizable organic matter. Decomposition is accelerated by metal contamination and is accompanied by the liberation of heat and oxygen, which will support combustion and explosions in confined spaces. The material is a n irritant to the skin and mucous membranes and dangerous to the eyes Mechanism: Hydrogen peroxide is a weak acid and ionizes in water to form a hydrogen ion and a perhydroxyl ion. The perhydroxyl ion is the active bleaching agent.

Hydrogen peroxide can also decompose. This reaction is catalyzed by metal ions e.g. Cu++, Fe+++. This reaction is not desired in bleaching because it is a n ineffective use of hydrogen peroxide and causes fiber damage.

Effect of pH: Hydrogen peroxide is a n extremely weak acid, Ka = 1.5 X 1012. Since the perhydroxyl ion is the desired bleaching specie, adding caustic neutralizes the proton and shifts the reaction to the right. Therefore: 1. at pH < 10, hydrogen peroxide is the major specie so it is inactive a s a bleach. 2. At pH 10 to 11, there is a moderate concentration of perhydroxyl ions. pH 10.2 to 10.7 is optimum for controlled bleaching. Sodium hydroxide is used to obtain the proper pH. 3. At pH > 11, there is a rapid generation of perhydroxyl ions. When the pH reaches 11.8, all of the hydrogen peroxide is converted to perhydroxyl ions and bleaching is out of control. Effect of Time and Temperature; Stabilized hydrogen peroxide does not decompose at high temperature therefore faster and better bleaching occurs at 95 to 100 0C. This feature makes it ideal for continuous operations using insulated J-boxes or open-width steamers. STABILIZERS: Stabilizers must be added to the bleach solution to control the decomposition of hydrogen peroxide. Stabilizers function by providing buffering action to control the pH a t the optimum level and to complex with trace metals which catalyze the degradation of the fibers. Stabilizers include sodium silicate, organic compounds and phosphates. 1. Sodium Silicates: Sodium silicates are the most commonly used and most effective hydrogen peroxide bleach stabilizers. They may be used as colloidal silicate (waterglass), ortho silicate or


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metasilicate. The mechanism by which silicate stabilize is not completely understood, however it is known that silicates have a natural affinity for ferrous ions and ferrous ions are naturally present in cotton. It is possible that the silicates are adsorbed onto the ferrous ions in the fiber, producing a species t h a t catalytically enhances bleaching while reducing bleach decomposition and fiber damage. Stabilization by silicates is enhanced by the presence of magnesium ions. Magnesium serves as a pH buffer. As the concentration of OH- rises during bleaching, magnesium hydroxide (Mg(OH)2) precipitates, reducing the OH- concentration. Bleach solutions containing only magnesium ions have good stability but the bleaching effectiveness is not a s good as when silicates are included. Silicates as stabilizers have one drawback, they tend to polymerize and form insoluble silicates. They becomes hard deposits which build-up in the machines causing the fabric to be abraded. Also some of the deposits will form in the cloth, giving it a harsh, raspy hand, a real negative for terry toweling. 2. Organic Stabilizers: Organic stabilizers avoid the problems associated with sodium silicates. These products are often referred to as silicate free or non-silicate stabilizers. They may be based on sequestering agents, protein degradation products or certain surfactants. The commercial products are of two types, those designed only to be stabilizers and those which combine stabilization with other properties such as detergency and softening. For some bleaching methods, organic stabilizers may be used alone, while in others, they are best used in combination with silicates. 3. Phosphates: Tetrasodium pyrophosphate (TSPP) and hexametaphosphates are of interest as stabilizers in alkaline bleach baths under the following conditions: 1. The alkalinity of the bleach must not be higher than pH 10 since above this, the stabilizing effect decreases rapidly. 2. Temperature of the bleach bath is limited to 60 0C. Higher temperatures reduce stabilizing properties. They should be used with ammonia, not caustic soda or soda ash. TSPP at high pH and temperature is converted to trisodium phosphate which has little stabilizing effect. The use of TSPP is limited to bleaching wool and silk which are sensitive to high pH and high temperatures. As opposed to silicates, pyrophosphates are precipitated from solution in the presence of calcium and magnesium and therefore do not develop full stabilizing power. Uses: Hydrogen peroxide is the bleach most widely used for cellulosic fibers [cotton, flax, linen, jute etc.) and well as wool, silk, nylon and acrylics. Unlike hypochlorites, peroxide bleaching does not require a full scour. Residual fats, oils, waxes and pectines do not reduce the bleaching effectiveness of hydrogen peroxide. Additionally it can be used on continuous equipment. Since it ultimately decomposes to oxygen and water, it doesn't create effluent problems.


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Typical Bleaching Procedures: 1. Batch

2. Continuous

2) Neutral wash

i. Formic acid

It is used to neutralize the remaining chemicals of the half bleach.

3) Killer

It is use for further neutralization to remove remaining hydrogen peroxide and caustic soda.


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4) Dyeing

i. Hub Salt

It is use to open the pores of the fiber and for pushing of the dyeing to the fiber.

ii. Soda ash

It moves the dye molecules towards the yarn.

iii. Caustic soda

It has more ph value then soda ash and it is also inexpensive therefore it is used in minute quantity to save the expenses of soda ash. For high quality shade only soda ash is used.

5) Neutral wash/soaping i. Formic acid

It use for neutralization.

ii. Multiwash A-9500

It is used to remove the suspended dye particles.

6) Fixing

i) Alco fix R

For the fixation of dye molecule after soaping.

7) Finishing

I. Acetic acid II. Alkamine CWS (paste)

These are use for neutralization.


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HYDROEXTRACTOR

Loading capacity 24 32 or 40 packages per cycle with production up to 400 packages per hour. Built in stainless steel AISI 316 it does not need any civil work to be installed and works at a speed of 1.250 RPM. Suitable for small and medium productions.

Dryer

Drying system use the delicate passage of hot air through the packages after hydro extraction. This system is now the most common among the dyeing houses around the world because of the very low energy consumption and the high quality of drying.

Lay-out packages dryers


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STORE ROOM

Incharge Mr. Ali

Labour 8

shift 1 (12 hours)

Machines 1 - Air Tec packing machine 2 - Scale (weigh machine) 1 - Air Tec packing machine It is used for the packing of export quality cones. 2 - Scale weigh machine It is used to weigh the cones. Note:- Each carton contains 40 cones.

Wt. of export quality cone = 1.63 Kg

Wt. of export local cone = 1 Kg

Wt. of export commercial cone = 0.36 Kg

One big cone makes 3 baby cones. LOT TYPES

a) Big lot 504 cones (15 bags with one small bag each bag contain 35 cones).

b) Medium lot 161 cones (6 bags)

c) Small lot 15 cone (1 bag)

comfort mill report on yarn dyeing

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Transcript of comfort mill report on yarn dyeing