Polyester Microfibers:- Dyeing and Wet Processing

Microfiber

A synthetic fiber that is extremely soft, lightweight, breathable, durable and ultrafine. In fact, microfibers are two times finer than silk and one hundred times finer than a human hair. Microfiber is currently manufactured from acrylic, nylon, polyester and rayon.Ultra-microfibers on the market are even finer – some having thickness of just 1/200th the thickness of human hair!

Microfibres refer to staple fibres, or individual filaments within yarns, which have fineness less than 1 decitex ( 1 grams per 10,000 meters) and For any fiber to be classified as microfibre yarn, the weight per 10,000 metres of yarn (dtex) is divided by the number of filaments (f), the result must be below 1.
All about microfibers

Microfibers: Functional Beauty

Properties of Polyester Microfibers

1. Lightweight and flexible
2. 
   
   Good stability and shape retention
3. 
   
   Anti-wrinkle property
4. 
   
   Have a wicking ability that permits perspiration
5. 
   
   Comfortable to wear as they are more spongy
6. 
   
   Doesn't water stain - superior water repellency is available
7. 
   
   Woven or knitted into a very high quality fabric construction
8. 
   
   Formerly commenced as a polyester microfiber, today you can find nylon, rayon and acrylic microfibers too.
9. 
   
   Strong and durable, water repellent and wind resistant -so tightly woven, that the fabric can't be penetrated by wind, rain or cold
10. 
    
    Lightweight, resilient or resist wrinkling, have a comfortable array, preserve shape and resist pilling
11. 
    
    The positively charged microfibers draw dust; the tiny fibers are capable to enter the microscopic surface voids most materials
12. 
    
    Washable, dries quickly and also washable in at the water temperatures up to 200 degrees and their characteristics will remain intact.
13. 
    
    Electrostatic effect - Hair, lint and other dust particles are attracted and grabbed by the microfibers without lifting dust.
14. 
    
    The density of the material allowable it to grip six to eight times its weight in water hence high absorbing power capacity
15. 
    
    The attraction capability of the microfibers is so sound, even absorbs bacteria and germs - hence can be use as germ or bacteria free purpose
16. 
    
    The fabric consists of millions of small tiny conduits that carry oil and grease too.
17. 
    
    Benefits of microfibers
18. 
    
    Comfortable - very soft, texture like silk, lightweight
19. 
    
    Due to its fineness and superior fiber surface area making deep, rich and bright colors achievable
20. 
    
    Less "sweaty" in warm weather than usual synthetics
21. 
    
    Quickly cleanable - clean just with water
22. 
    
    Highly intense and shrink-resistant
23. 
    
    Presents insulation and breathability
24. 
    
    Change without help - to establish lovely drape
25. 
    
    Very fine - finer than the most precise silk
26. 
    
    More reusable for cleaning alternative - compared to other mops more efficient and long life

Dyeing of polyester Microfibers
Due to their fineness, the total surface area of microfibre yarn or fabric is far greater than ordinary fibres. Threfore

1.Due to its special structure ,micro fibers has much larger quantity of size ,oil agents and wax on warp yarns.

2.Since microfibres have very small interstitces, with consequent difficulties of size accessibility and duffusibility, desizing becomes quite difficult and costly.

3.Microfibres have greater absorption area resulting in a dyeing rate four times higher than that of normal, which can cause unlevelness in dyeing.

4.They also require more dyestuff than standard fibres to obtain the same depth of shade.
5.Larger external surface means an increase in number of threads exposed to light which, on destruction of dye, is expressed as lower light fastness rating.
6. Wash fastness and color fastness to rubbing is also poor.
7.Staple microfibres offer difficulty in carding.

The problems in wet processing of microfibers can be overcome by

1.Better knowledge about the size applied and optimum parameters during desizing operation.

To achieve satisfactory dyeing effects ,desizing and refining process must be done before dyeing and after desizing and refining , there should be no impurities left such as electrolyte, antistatic finishing agent , spin finishes and blot.

2.Pre-setting

Suitable pre setting conditions ( time ,temperature and tension) helps not only in stable dimensional stability ,softness but also better dyeing results.

3.Alkali weight reduction

Alkali weight reduction s to treat the fabric with concentrated alkali at high temperature.fber molecule hydrolyse under this condition and lose some weight with change in properties, thus space occurs between crossing points and rubbing resistance relative to slippage among yarns becomes small.Alkali weight reduction makes fabric soft, liveliness, limber and improved absorption.

2.Careful selection of the dyes.

Proper dye selection which are
1.Compatible
2.Having same exhaustion rates
3.Having high wash fastness properties.
4.Good migration and levelling properties
 eliminates problems regarding build-up and fastness properties.
Disperse dyes for polyester microfibers

3.Optimizing the dyebath conditions and dyeing cycle.


Optimised dyeing cycles can be worked out by controlling the temperature to account for the high rate of dyeing and to eliminate the risk of uneven dyeing.Chemicals and dyes to be added at, at least 10-20 deg.C lower temperature than normal polyester fiber dyeing. The additions of dyes must be progressive or devided at least into 4 parts. The heating rate must be slow from 40 deg C to 100 deg C. 10-20 min more holding time required at 130 deg C as compared to normal PES.


4.Proper selection of  Dyeing machinery.

The dyeing machine must have the required automation to fufil the requirements of microfiber dyeing such as microprocessor controlled dosing , proper and accurate heating rate control etc.


5.Proper selection of dyebath additives
such as
Levelling agents :- A strong levelling agent which shall start working at lower temperatures.
Dispersing agents :- Higher quantities of dispersing agents are needed because amount of dyes required are more to produce the desired depth.
Chelating agents:-
Anticreasing agents,Dyebath softners/Lubricants :- Because microfiber textiles are prone to creasing , therefore use off dyebath lubricants is must.

6.Proper aftertreatment of dyed goods.
Soaping :- In order to obtain satisfactory color effect , fabric should be soaped after dyeing .Soaping is the key process to achieve satisfactory dyeing results on polyester especially polyester / nylon microdenier fabric.


Reduction clear :-Good reduction clear process is needed to achieve satisfactory washing , rubbing and light fastness properties.
Washing :-Is required for neutralising and removing alkali after reduction clear treatment.
Softening, anti soil and antistatic treatment :-Because microdenier fiber easily stains and produces static charges, a hydrophilic ,antistatic and antisoil treatment besides softening is highly recommended to ensure fabric softness and comfortability.

Recommended Dyeing Cycle for polyester Microfibers

Dianix PLUS( Dystar) or Longsheng  is a new range of five compatible, level-dyeing dyes for reliable dyeing of medium and heavy shades, especially on microfiber and weight-reduced polyester, whether applied under mild alkaline conditions to control trimer, or under conventional acid conditions.
Dianix E-PLUS" for Pale Shades on Polyester Fabrics
Fashion application of polyester

Application of polyester Microfibres

Microfibers are most commonly found in polyester and nylon. Some rayon and acrylic micros are in production and available to consumers. Micros can be used alone or blended with conventional denier man-made fibers as well as with natural fibers such as cotton, wool, and silk.

In textiles

Microfibers are used in a variety of fabrics, but most commonly in dress and blouse weight garments. Suit jackets and bottom weights are becoming available. Look for micros in lingerie, rainwear, outdoor fleece and wind-resistant sportswear, as well as tents, sleeping bags, track and jogging suits. The strength of microfibers make them particularly adaptable to sueded or sandwashed finishes because of their extensive fiber surface area and the use of strong fibers like polyester and nylon. As a result, many microfibers simulate the appearance of sandwashed silk.

Other Main products for which microfiber are ideally suited:

• Microfiber Glass Cloth

• Duster/Multi-purpose Microfiber Cleaning Cloth

• Microfiber Scrubber

• Microfiber Kitchen Cloth

• Microfiber Optical & CD Cloth

• Microfiber Mops

• Microfiber Cleaning Sponge

• Microfiber Cleaning Cloths – Terry Cloths, Suede Cloths, Waffle-Weave Cloths

Microfiber Makes the Grade
http://www.tex.in/education/nextiles/fib/mic/mic.html
http://ygmfranchise.blogspot.com/2007/07/cleaning-tips-microfiber.html
http://www.microfibergreen.com/is-microfiber-green-product.html
http://www.norwexnow.com/microfiber%20science.html

 

Paddle Dyeing Machines

Paddle dyeing machines

A process of dyeing textiles in a machine that gently move the goods using paddles similar to a paddle wheel on a boat. This is a slow process, but there is extremely little abrasion on the goods.

Horizontal Paddle Machines (over head paddle machine) consist of a curved beck like lower suction to contain the materials and the dye liquor. The goods are moved by a rotating paddle, which extends across the width of the machine. Half immersed paddles cause the material to move upwards and downwards through out the liquor. The temperature can be raised to 98o C in such system.

lateral / oval paddle machines consist of oval tank to enhance the fluid flow and the processing the goods. In the middle of this tank is a closed oval island. The paddle moves in a lateral direction and is not

half submerged in the liquor and the temperature can be increased up to 98o C.

HT Paddle Machines work according to the principle of horizontal paddle machine, however, the temperature can be raised up to 140o C. PES articles are preferably dyed on HT paddles. In paddle machines, the dyeing can be carried out with 30:1 to 40:1, lower ratios reduces optimum movement of the goods, lead to unlevel dyeing, crease formation. For gentleness, the blades of the paddle are either curved or have rounded edges and the rotating speed of the paddle can be regulated from 1.5 to 40 rpm. Circulation of the liquor should be strong enough to prevent goods from sinking to the bottom. Paddle machines are suitable for dyeing articles of all substrates in all forms of make ups. The goods arenormally dyed using PP/PET bags.

Winch Dyeing Machines

Winch dyeing

A dyeing machine consisting essentially of a dye vessel fitted with a driven winch ( usually above the liquor level) which rotates and draws a length of fabric, normally joined end to end, through the liquor.

Winch dyeing machines are a low cost design that is simple to operate and maintain, yet versatile in application proving invaluable for preparation, washing or after treatments as well as the dyeing stage itself. In all winch dyeing machines a series of fabric ropes of equal length are immersed in the dye bath but part of each rope is taken over two reels or the winch itself. The rope of fabric is circulated through the dye bath being hauled up and over the winch throughout the course of the dyeing operation. Dyestuff and auxiliaries may be dosed manually or automatically in accordance with the recipe method.

Description  and Dyeing Method on Winch Dyeing Machine

The basic principle of all winch dyeing machines is to have a number of loops or ropes of the fabric in the dye bath, these ropes are of equal length , which are mostly immersed in the liquor in the bath. The upper part of each rope runs over two reels which are mounted over dyebath. At the front of the machine , above the top of the dye liquor , is a smaller reel, which is called jockey or fly roller. The fly roller remain free wheeling along with fabric rope. At the back of winch tank is the winch wheel, which pulls the fabric rope from the dye bath over the jockey reel for dropping in the dye bath for immersion. From the dropped location , the fabric rope travels back . to be lifted and fed to winch wheel.

The dyeing process on winch dyeing machines is based on higher M:L as compared with other dyeing machines. The process is conducted with very little tension . The total dyeing time is lengthier as compared to other machines.

Advantages of Winch Dyeing
a. Construction and operation of winch are very simple.
b. The winch dyeing machines are suitable for types of wet processing operations from desizing to softening.
c.The winch dyeing machine is suitable for practically all types of fabrics ,which can withstand creasing in rope form processing.
d. Thr tension exerted on winch is less than jigger,the material thus dyed is with fuller hand.
e. The appearance of the dyed goods is clean and smooth on winch dyeing machines.

Limitations Of Winch Dyeing
a. Batch dyeing operations needs trimming, sewing, opening out the rope , loading and unloading for individual lots separately.
b. Since several lengths of fabric are run over the winch reel into the liquor and sewn end to end,Continuous length processing is not possible in a single batch.
c. Fabric is processed in rope form which may lead to crease marks , particularly in heavy , woven , thin and light synthetics.
d. Most of the machine work under atmospheric conditions.
More Information On Winch Dyeing Clik Here
Winch Dyeing Machines
Fabric dyeing Machines

Pad Dyeing Machines

Padding Mangles


The pad dyeing machines overcome the deficiency of winch and jigger dyeing machines of smaller batch size and discontinuity in dyeing. Padding mangle offer continuous process of the fabric in concerned liquor , such as pretreatment, dyeing or finishing.
Application of dyestuffs is conducted in the pad dyeing machines with single or multiple dipping in solution .During padding, the fabric passes into a solution of chemicals, under a submerged roller and out of the bath. It is then squeezed to remove excess solution .The objective of this process is to mechanically impregnate the fabric with the solution or dispersion of chemicals Pad impregnation is common for the dyeing of fabric and for the application of finishing chemicals.

A Practical Introduction to the Continuous Dyeing of Woven Fabrics

Machine Description

Main parts of a padding mangle

The main frame

The frames are usually fabricated construction , to withstand vibrations and heavy workloads.

Tension elements

While the cloth passes on to the padding machine no slackness should occur in fabric either in weft or warp directions and the weft threads of cloth should remain parallel to the nip at the squeezing point.

The padding mangle bowls

The nip rollers (often called bowls) are the key to successful pad dyeing. In general, two-bowl nips are preferred for lightweight or standard fabrics running at moderate speeds, whereas three-bowl arrangements are intended for heavier or more densely woven qualities that may be more difficult to wet out and thus require a double-dip and double-nip treatment.

Cloth Guiding arrangement

Are provided so that machine should have a universal feeding and delivery system at a uniform tension .

Pressure generation and application

It is either pneumatic or hydraulic.

The dye trough

The pad trough is usually a deep U-shaped vessel with a single roller attached to the base of a displacement block that leaves a narrow passage to accommodate the moving fabric.
A cost study of thermosol and continuous solvent dyeing

Dyeing Method

The padding operation itself consists of two essential steps: thorough impregnation by immersion of the absorbent fabric in a dye solution containing a wetting agent, followed by squeezing of the wet fabric between rollers to expel air and replace it with dye liquor, as well as expressing surplus liquor back down the sloping fabric surface to the pad trough.

The cloth to be padded is taken up by either from the folded form or from the batched condition and fed to the padding machine over a set of guide rollers. The fabric is straighten in warp as well as weft directions .It is necessary to attach and end piece on both the sides of batch.

The fabric to be padded should be padded should be pretreated , free from loose fly ,waste ,oily matter , flat , crease free and with opened-out selvedges.

To obtain consistency of shade it is most important that the fabric running speed and the length of immersion of fabric in the dye liquor remain constant throughout the padding run. The three main types of automatic level control are:

1. Float switches: these are reliable and are unaffected by foam but they are relatively bulky

2. Conductivity probes: these are small and neat but foaming of the pad liquor adversely affects their performance

3. Differential pressure detectors: those with a hollow tube projecting downwards from the liquor surface are difficult to clean and the preferred type is that with a closed diaphragm set in the base of the vessel.

4. The control of pad liquor temperature is highly desirable to achieve consistent results.

Further Readings
 Jet or pad/wet steam dyeing of tublualr knitted cotton fabrics with reactives: Which costs less? : a summary report (Hatra research report)
Pad-batch Dyeing of Plant Fibres (Rural Technology Guide)

Jigger Dyeing Machines

About Jigger
Jigg or jigger dyeing machine is one of the oldest dyeing machine used for cloth dyeing operations. Jigger machine is suitable for dyeing of woven fabrics, up to boiling temperature without any creasing . Jigs exert considerable lengthwise tension on the fabric and are more suitable for the dyeing of woven than knitted fabrics. Since the fabric is handled in open-width, a jig is very suitable for fabrics which crease when dyed in rope form.
Some wovens are conveniently dyed on jigger are ,
a. Taffettas
b.Plain wovens
c.Satins
d.Poplins
e.Ducks
f.Suiting and Shirting material.
g.Sheetings etc.
but have limited application on fabrics which are tension sensitive such as crepes , flat crepes , knits , net fabrics and elastomeric warps etc.
Machine Description
The jigger machines have two main rollers which revolve on smooth bearings and are attached to with a suitable driving mechanism , which can be reversed when required. The fabric is wound on one of the main rollers and fed from the other. The fabric move from one roller to the other through the dye liquor trough located at the lower part of the machine . There are various arrangement of guide rollers at the bottom of liquor trough ,and during each passage the cloth passes around these guide rollers .
The concentrated dye liquor is usually introduced directly into the dyebath in two equal portions, which are added just before commencing the first and second ends. The liquor is agitated by the movement of the fabric through the dyebath. Several horizontal spray pipes are fitted across the full width of the trough in order to expedite fabric rinsing.
Live steam injected into the bottom of the trough through a perforated pipe across the width of the jig heats the liquor. Some modern jigs also have heat exchangers for indirect heating.
Covering the top of the jig minimizes the heat loss to the atmosphere, keeps the temperature uniform on all parts of the fabric and minimizes exposure of the liquor and the cloth to air. Minimizing exposure to air is important when using sulphur or vat dyes since these dyes can be oxidized by atmospheric oxygen.
A few meters of leading fabric, similar in construction to the cloth under process, is stitched to each end of the cloth batch , to allow the entire length of the fabric to pass through the dye bath during the dyeing process. When jig processing is completed, the fabric is run onto an A-frame via a nip or suction device to remove extraneous water during unloading.
Modern machines such as automatic and jumbo jiggers have full automation in drive , tension regulation and control , fabric speed and metering, smooth and jerk less stop and start , counters for number of turns , gradual and noiseless reversal, automatic temperature regulation and control etc.

Dyeing process on Jigger

The dyeing process on jigger is regarded as a series of intermittent padding operation followed by dwelling periods on the main roller , during which the dyeing action and diffusion takes place. The factors controlling the rate of dye absorption are:

1.The amount of interstitial dye liquor retained in the interstices of the fabric weave.

2.The exhaustion of the interstitial liquor in the dwell period between successive immersions.

3.The degree of interchange of liquor during one immersion (interchange factor).

In the dyeing on jigger machines the cloth revolves on two main rollers , The open-width fabric passes from one roller through the dyebath at the bottom of the machine and then onto a driven take-up roller on the other side. When all the fabric has passed through the bath, the direction is reversed . Each passage is called an end. Dyeing always involves an even number of ends. The dye bath has one or more guide rollers , around which the cloth travels , and during this immersion achieves the desired contact with the dye liquor. During this passage the fabric picks up adequate quantity of dye liquor , excess of which is drained out but still a good quantity is held in the fabric . During rotation of rollers this dye penetrates and diffuse into the fabric. The real dyeing takes place not in the dye liquor but when the cloth is on the rollers, since only a very small length of fabric is in the dyebath and major part is on the rollers . Therefore the speed of cloth during immersion in dye liquor has a very little effect on percentage of shade produced.

see video click here

Some critical problems related to the conventional jigger dyeing machines ( which are minimized in the modern day machines) The major problems are side-to-centre color variations, called listing, and lengthways color variations, called ending.

Other problems are

• Temperature control from side-to-side and end-to-end of the roll

• Tension control from end-to-end

• Constant speed control from end-to-end

• Prevention of creases

• Prevention of air

Limitations of jigger Dyeing

1.Jigs exert considerable lengthwise tension on the fabric and are more suitable for the dyeing of woven than knitted fabrics.

2.In textile preparation due to the swelling and dissolution of size, which makes the fabric slippery and unstable in roll form.

3The low liquor ratio makes washing-off difficult.

4.There is little mechanical action in a jig machine and it is less suitable where vigorous scouring is required before dyeing.

5.Moiré effects or water marks may arise on some acetate and nylon fabrics because of pressure flattening the structure of the rolled fabric.

New Developments in this Field

Click here

Read More About Jigger Dyeing
Jig Dyeing Machine
Click here 1
Dyeing

Jet Dyeing

Jet Dyeing Machine

A machine used for dyeing of fabric in rope form.Jet dyeing machines came into existence with a purpose to minimise or eliminate the drawbacks of earlier machines like winch , jigger and beam dyeing units.

Principle of the Technology

Jet dyeing is a process that can be used for batch dyeing operations such as dyeing, bleaching, washing and rinsing. In this process, dyeing is accomplished in a closed tubular system, basically composed of an impeller pump and a shallow dye bath. The fabric to be dyed is loosely collapsed in a form of a rope, and tied into a loop. The impeller pump supplies a jet of dye solution, propelled by water and/or air, whch transport the fabric within the dyeing system ,surrounded by dye liquor , under optimum conditions. Turbulence created by the jet aids in dye penetration and prevents the fabric from touching the walls of the tube, thus minimizing mechanical impact on the fabric.

see video jet dyeing machine 

Special Features and Applications

1.Jet dyeing machines can be operated even at high temperatures and pressures. Jet dyeing systems are fitted with cooling systems with the potential for reuse of the warmed water on the next dyeing cycle.

2.Jet dyeing systems operate at a low liquor ratio, or the ratio of the mass of the dye bath to the mass of the fabric in the dyeing machine. Compared to conventional dyeing, typically with a liquor ratio of 1:15 to 1:25, jet dyeing can be operated at a liquor ratio from as low as 1:3 up to 1:6. Consequently, the dyeing operation consumes less water and chemicals, and generates less effluent.
3.Since the dyeing process depends on dye concentration, the lower liquor ratio increases the dyeing rate and dye fixation.
4.Increased dyeing rate results to quicker machine drains and fills, and more rapid heating and cooling. The latter decreases energy requirements for heating the dye bath, which then leads to reduced steam and boiler use, reduced fuel consumption, and fewer emissions to the atmosphere from combustion.
5.The lengthwise tension is less , widthwise tension is absent and fabric achieves better fullness and handle.
6.The frequent movement of fabric round the jet through the machine reduces the tenedncy of crease formation.
Limitations of Jet Dyeing machines
1.High Initial investments and maintenance cost.
2.Limited accessibility during the dyeing process.
3.Foam forming substances are to be avoided.
4.Any roughness of the  inside surface cause damage to cloth.
5.In case of cloth breakage , rethreading is complicated.
Types of Jet Dyeing Machines
After incestifating the dyeing results under different conditions such as development of new fiber blends , different construction fabrics,interaction position of jet,quantity of the dyeliquor to be  present in around the fabric and the type of impact of the dyeliquor on the fabric in the jet area, the following type of jet dyeing machines were developed,
1.Fully flooded jet dyeing machines click here
2.Soft flow Jet dyeing machines Click here for details
3.Low liqour ratio . reel jet dyeing machines. Click here for details .

Watch animated working principle  of jet dyeing  machine.

HTHP Package Dyeing Machines

High Temperature Dyeing Machines (Guidance Note)
Package dyeing machines are the most widely used now a days for dyeing of almost all type of yarns ,due to economical ,automatic and accurate dyeing results. The term package dyeing usually denotes for dyeing of any type yarn wound on the compressible dye springs/perforated solid dyeing tubes or cones. Yarn dyeing in package form is done at high temperature and under high pressure ,with the packages mounted on hollow spindles .These spindles are fixed on the dyeing carriers ,which is inserted into the dyeing vessel after closing the lid of the machine ,the dyeing liquor is forced through the packages in two way pattern (inside to out and outside to in) and goes on circulating throughout the vessel and yarn. Heat is applied to the dye liquor to achieve the dyeing temperature, time –temperature and flow reversal are controlled through a programmer.

All operations from pre treatment to finishing can be performed in the same machine ,without taking out the material out of the machine.

A series of technical developments in the recent past has resulted into package dyeing machine being developed into a highly sophisticated dyeing equipment.

The main advantages of package dyeing over other yarn dyeing methods are

1.The material is dyed on cross wound packages ,therefore bigger unit weight( 1.2 kg -1.5 kg for cotton) in dyeing is possible. The bigger weight makes the process sequence from winding to end use economical due to less handling and less changeovers.

2.Economical dyeing due to lower liquor ratio, compact and enclosed dyeing vessels .different liquor ratio is possible in different process steps such as partial filling in washing and soaping and fully flooded in rinsing make the process economical.

3.More uniform dyeing is possible due to higher number of contacts at high and optimized flow rates .The automatic flow control through programmer in critical steps and depending upon the material permeability make the processing trouble free.

4.High temperature ,high pressure and high flow rates results into shorter dyeing cycles.

5.Due to complete automation ,the machines are less labor intensive.

6.Modern machines with partial loading spindles are more flexible for different size lots ,the air pad system allows to maintain the material to liquor ratio and automatic flow control system maintains the flow through the packages ,thus whether the machine is fully loaded ,partially loaded or half loaded ,the dyeing parameters remain the same and results into better reproducibility as well economical dyeing.

7.Bigger dye lots are possible by coupling or linking one ,two, three or even four similar machines. The machines after linking works as a single unit and same shade is produced as a single lot. The coupling allows to serve the bigger lots without going for such bigger machines .The use of coupled machines makes the market service more efficient.

8.Very less handling and damage to dyed substrate ,due to shorter dyeing cycles.

9.All operations from pretreatment to hydro extraction in single machine are possible.

10.The package dyeing machines are more versatile because almost all type of substrates can be dyed and almost all types of dyestuffs applications is possible.

11.The same machines can be used for multiple make ups such as yarn, fiber, tow ,tops, bumps and beams on suitable dyeing carriers.

12.Certain new developments and instrumentation allows to go to very high flow rates

( more than 50 ltrs/kg/minute) without channeling or damaging the yarns and shortening the dyeing cycles considerably. Most advanced machines are equipped with pH regulators and controllers and salt sensors to for achieving very reliable and reproducible results.

Main parts of the machines
1.Main kier or the main vat in which the actual dyeing is being carried out.
2.Expansion or addition tank
3.Stock or preparation tank
4.Main pump
5.Injector or dosing pump
6.Dyeing carrier
7.Sampling device
8.Back cooler in fully flooded models
9.Control panel
Working of Package Dyeing machines

The material to be dyed is wound on the dye springs, perforated plastic cheeses or steel cones and loaded in the carrier spindles ,which are compressed and bolted at the top to make a uniform and homogeneous dyeing coloumn. The liquor containing dyes chemical and auxilliaries is forced through with the help of pump, and circulated through the material from inside –out and is reversed periodically so that each and every part of the material get the same and uniform treatment. The dyeing cycle is controlled through a micro computer and different chemicals may be added through the injector pump or color kitchen at any stage of dyeing.

In case of fully flooded machines ,the liquor expands with the rise in temperature (approximately 5% volume increases from 30-130 degree centigrade temperature) is taken back in the expansion tank through a back cooler. This extra water is then again injected to the dyeing vessel through an injector pump. Expanded volume of the dye liquor is thus remains in continuous circulation in the system.

Any type of addition can be done to the machine through the injector pump, the quantity and time of injection can be controlled through the programmer.

In case of air pad machines ,the air above the liquor acts as a cushion ,which is compressed with the increase in liquor volume, the pressure is controlled by pre set pressure control valve .In air pad machines have an advantage ,that entire dye liquor participate in dyeing and dye exhaustion is perfect. In case some addition has to be done in air pad machines , if the machine temperature is less than 80 degrees ,the liquor is taken back by back transfer valve to addition tank ,and injected back to machine vessel. If the machine temperature is above 80 Degree then cooling has to be done to bring down the machine temperature.

Air pad technology is possible in all types of machines such as vertical kier, horizontal kier and tubular dyeing machines.

The material after dyeing is washed and finished properly in the same machine and taken out hydro extracted or pressure extracted in the same machine and dried subsequently.

Yarn Package Dyeing Machine Instruction :- Animated Video

The dyeing of cotton in high-temperature dyeing machines (Technical circulars)
Different type of Package Dyeing Machines are
1.Vertical Kier Dyeing Machines
2.Horizontal Kier Dyeing Machines
3.Tubular Dyeing Machines
The dyeing of viscose rayon with direct and vat dyestuffs in high-temperature dyeing machines (Technical circulars)

Vertical Kier Dyeing Machines

These machines have a vertical cylindrical dyeing kier, in which material loaded into carriers with vertical perforated spindles, is dyed .The machine could be fully flooded or air pad type .These are high pressure machines and suitable up to 1350C temperature dyeing.

Horizontal HTHP Dyeing Machines

These machines are similar to vertical type machines in which the cylindrical dyeing kier is in horizontal position. The dyeing carriers with vertical spindles are used in these machines, which are inserted into the machine via trolleys. These machines are erected at the ground level and hence do not need an overhead hoist as well as platform, thus making the dyehouse design and layout is simple .
See video here

Tubular HTHP Dyeing Machines

These machines may be of vertical or horizontal type ,and have one or many tubes acting as small dyeing vessels, each with a single individual spindle. The spindle is taken out of the tube ,loaded and then inserted back into it. These machines can be operated either fully loaded tubes or to partial loads by using dummies. Since all individual tubes in a machine are connected and serviced by a main pump, therefore it is also possible to operate as many tube as required and disconnecting others.

These machines can be erected at ground level and hence do not need a platform or hoist.

These machines are most flexible as for as the capacity variation is concerned ,without altering the material to liquor ratio.
Explore More
About Package Dyeing Machines Click Here
Dyeing Machine Controllers Click Here
Package Dyeing Machines Click Here 
Vat Dyeing in Package dyeing machines Click Here

Hank Dyeing In HTHP Machines

Dyeing of hanks in multipurpose HTHP dyeing machines The HTHP dyeing machines can also be used for dyeing and bleaching of yarn in hank form ,by using suitable carriers on which the hanks can be loaded. The fiber dyeing carriers can also be used in which the hanks are piled ,just like in kiers, and dyeing or bleaching can be done. The last method is useful for hard twisted and coarser yarns, which are difficult to penetrate under normal atmospheric conditions of cabinet dyeing machines. The hanks are loaded into suitable dyeing carriers , which are having either straight sticks or circular sticks for loading of hanks. The hanks of different sizes can be accommodated as in the case of cabinet dyeing machines. The carriers are then put into the dyeing machine kier and rest of the process is carried out as in case of cheese dyeing . The flow rate and reversal of dye liquor direction are optimized as per the quality of the yarn.

Spray Dyeing Machines

1.Lid
2 .Regulation valve
3 .Addition/expansion tank
4 .circulating pump
5.window
6. injection tube( spray arm)
7.Collection tank Intake
8.Machine body

These machines can be defined as an improved version of roller dyeing machines or hybrid type of machines with combination of features of roller dyeing and cabinet dyeing.

The features incorporated in these machines are especially important to overcome the problems related to delicate yarns such as silk , viscose and wool yarns.

These machines are made of rectangular shaped box type enclosed main body, in which the spray arms are located ,there is collection tank with heating coils at the bottom.

These machines have removable loading arms ,same as in roller dyeing machines ,but having perforations for spraying the dye liquor from inside the rollers. These arms have an arrangement also fitted with suitable spray pipes for spraying the dye liquor from outside as well inside of the hanks . The arms rotate on their axis with the hanks thus spraying the dye liquor from both inside and outside of the

hanks ,covering uniformly the entire hank.. The excess liquor is collected at the bottom tank ,from which it is again fed to the spray system with the help of a centrifugal pump. The spray pressure and flow rate can be adjusted as per the material quality and type of hanks. The RPM and direction of rotation of the arms can be varied according to the yarn quality and process parameters, to get uniform dyeing results and to avoid the yarn entanglements.

Main features of spray dyeing machines are
1. The machines are specially built for processing of delicate yarns such as wool , wool blends, silk and viscose yarns.
2. the yarn is treated very gently , and have minimum mechanical abrasion , the impact of dye liquor turbulence on the yarn is also minimum ,thus minimum entanglement and mechanical damage during processing.
3. The liquor is fed through an inverted controlled centrifugal pump ,so the liquor circulation in liters / min/ kg can be adjusted as per requirement as well as when the machines are used at a reduced capacity.
4. Total liquor volume of the machines can be adjusted as per loading or number of arms in the use.
5. The entire dyeing cycle can be carried out in fully automatic mode with the help of with the help of microprocessor based programmer.
6. The arms can be removed and replaced easily, therefore it is also possible to keep a lot ready on a spare set of arms ,which can be easily replaced after the completion of a dyeing cycle. The machines can be used at reduced capacity by reducing the number of arms in operation and more flexible.
7. The machines are available with air pad facility to run the machine at higher temperature and pressure and also keeping the constant liquor ratio when used at reduced loading.
8. Similar machines can be coupled together for dyeing of bigger lots in the same shade.
9. The machines are equipped with a single addition tank ,which is used for injection of dyes and chemicals through a separate pump. Fully automatic machines can be connected with automatic color kitchen also.
10. The machines are equipped with a sampling device to draw a sample for shade inspection without interrupting the dyeing operation .

Cabinet Hank Dyeing Machines

These are the most popular hank dyeing machines, these machines are designed to have liquor flow parallel to the yarn and they work with low liquor ratios to save substantially in consumption of thermal energy ,water and chemicals.The material to be dyed in hanks is loaded on the sticks ,generally two sticks are used one at the top and other at the bottom. The bottom stick is used to avoid the yarn entanglement during the liquor flow. The carriers are loaded with the sticks having hanks ,the sticks are supported into slots made in the body of the carrier.

The loaded carriers are then put into the dyeing machine and door is closed. In a second variant of the machine , the machine is open at the top and career is loaded from the top , which ,a rubber gasket is provided around the periphery on which the machine career rest, and vessel is sealed by the weight of the career and material, thus making closed circuit. The liquor circulation and flow remains the same as in ordinary cabinet machine.

The dye liquor in these machines moves while the material remains stationary. The flow direction is reversed frequently to ensure level dyeing.

A cabinet dyeing machine consists of following main components,

1.Main dyeing vessel made of SS
2.Carriers for loading of hanks with SS sticks for loading of hanks.

3.An internal axial pump or an external pump for liquor circulation.

4.An indirect heating system(with internal or external heat exchanger)

5.An addition tank with injector pump

6.Prepartion tank

7.An internal or external sampling device
8.Color kitchen

Main features of the cabinet dyeing machines are,

1.These machines are most researched ,developed and technically advanced ,and these are most preferred choice for the dyeing of all types yarn in hank form.

2.Modern machines are more flexible and capable of partial or half loading ,without changing the M:L, by using either dummies or by using special loaders , which can be easily adjusted in the machines. The new machines are equipped with continuous variable volume control and monitoring system ,which maintains the M:L even at reduced load .

3.Machine capacities available with same material to liquor ratios ,from lab scale to 1000 kgs for bigger lot size. Coupling of similar capacity machines is also possible to get even bigger lots.

4.All features such as inverter controlled pumps ,dosing and automatic color kitchen and fully automatic dyeing controllers ,same as package dyeing machines are available in these machines.

5.These machines are suitable for dyeing of various sizes of hanks ( from 48” to 90 “) in different qualities such as cotton, viscose, cotton blends, acrylic, wool and its blends and nylon etc. without any problem.

6.The liquor ratio of machines varies between 1:10 to 1:15, depending upon the machine and quality of material to be processed.

7.In the machines with air pad technology , the air pad acts as a air cushion to take care of expanded dye liquor and it is possible to work with higher pressure and temperture The machines with air pad are capable of working up to a maximum temperature of 135 0 C and there is no need of an extra heat exchanger to cool down the expanded dye liquor. Since the machine works in a closed circuit mode ,therefore the entire dye liquor participate in the dyeing.

8. The machines may be having a preparation tank with a quick transfer pump for faster liquor transfer from and to the machine without losing time and reducing the overall dyeing cycle. New machines are equipped with automatic color kitchen , multiple feeding and drainage points for more efficient and cleaner working.

9.The machines are equipped with an internal or external sampling device ,which allows the inspection of samples at any point of dyeing cycle ,without disrupting the actual dyeing process.

10. The machines with interchangeable extra careers offer mach more flexibility in terms of saving in loading /unloading time as well as automation of loading and unloading.

Roller Hank Dyeing Machines

Roller hank dyeing machines
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These machines are based on Hussong type of hank dyeing machines in design .These machines are very simple in design and operation. In the basic design of machine there is rectangular SS tank with proper heating mechanism (either a heating coil or direct steam injection through a perforated steam pipe) and have a false bottom above the heating coil.
The tank is fitted with a temperature indicator and control sensor. There is an array of SS rollers/poles which are fitted on a suitable frame .The rollers can rotate in clockwise or anticlockwise directions with the gears arrangement. The machine is fitted with a stop /start system to control the roller movement.
The hanks loaded on rollers can be lowered in the tank or lifted out by lifting or lowering the frame with the help of hydraulic system. The speed (RPM) of rollers can be varied by changing the gears and rotation cycles are controlled by timers which change the direction of movement of motors.
The dyeing vat have the filling and draining facility of dye liquor. The dyes and chemicals are added directly into the dye vat.
Operation of the machine
The hanks to be dyed are loaded onto the rollers bars by avoiding overlapping of hanks, in lifted position. The dye bath is kept ready with proper liquor level ,and mixed homogenously ,preferably with an external circulation pump .The hanks are lowered into the dye bath and movement is started , approximately 40-50% part of the hanks remain the liquor and rest is exposed to atmosphere . The material is lifted up for addition of colors ,chemicals ,salt, alkali etc or for raising the temperature of dye bath(in case of direct steam injection). In case of indirect heating the dye bath temperature may be increased at set rate of heating ,but in case of direct heating the temperature rise is step by step. The sample may be drawn at the completion of dye cycle and checked for shade, without stopping the machine. All operations can be done in the same machine

Advantages and disadvantages of Roller Hank Dyeing machines
1.Roller dyeing machines are simple in design and operation
2.Cost of the machine is not very high
3.Almost all type of dye classes such as direct, reactive, vat, naphthols, pigments, soluble vats can be applied to cotton ,mercerized cotton or rayon filaments.
4.All types of yarns can be processed such as cotton, mercerized cotton, viscose filament or even silk can be processed . The machines with simple modifications can be used to produce tie and dye effects in bigger lots particularly in cellulosic substrates.
5.The machine capacity depends upon the number of rollers ,which could be from 1 to even 10 rollers, and each roller can handle from 2 to 4 kg of yarn.
6.Only 40-50% of yarn takes part in dyeing and rest is exposed to atmosphere, therefore hydrosulphite consumption is high in these machines.
7.The machines are open type ,therefore maximum dyeing temperature is 95-98 0C .
8.The liquor ratio increases with heating in case of direct injection of steam.
9.Liqour ratio is high ,generally 1:15 to 1:20, therefore chemicals, steam and water consumption is comparatively high.
10.The yarn entanglements takes place during running which reduce the hank to cone winding efficiency.
11. Only limited automation is possible.
12. The dyeing is carried out under atmospheric pressure and there is no liquor pressure ,therefore the color penetration in hard twisted material is poor.