JIGGER DYEING MACHINE:-

JIGGER Dyeing Machine:

Objective, Dyeing Process, Advantages and Disadvantages:-

Jigg or jigger dyeing machine is one of the oldest dyeing machine used for cloth dyeing operations. Dyes use for dyeing fabric in Jig or Jigger dyeing machine which is suitable for woven fabric than knitted fabric because jigger exert considerable lengthwise tension on the fabric. This is also particularly suitable for cellulosic fibers because the natural dyes generally do not exhaust well and the jig works with an exceedingly low liquor ratio. Since the fabric is handled in open-width, a jig is very suitable for fabrics which crease when dyed in rope form. There are mainly two types of jigger dyeing machine for dyeing woven fabrics with dyes. One is open jigger dyeing machine and other is closed jigger dyeing machine. Normally after the process of dyeing machine, dyed fabric is sent to stenter machine.

Fig: Jigger Dyeing Machine.

Some wovens are conveniently dyed on jigger are,

.Taffettas

.Plain wovens

.Satins

.Poplins

.Ducks

.Suiting and Shirting material.

.Sheetings etc.

But have limited application on fabrics which are tension sensitive such as crepes, flat crepes, knits, net fabrics and elastomeric warps etc.

Types of JIGGER Dyeing Machine:

The types of jigger dyeing machine are

1)Textile jigger machine for woven fabrics

2)Hydraulic jigger machine for dyed fabric

3)Semi-automatic dyeing jigger for dyeing fabric

4) Automatic jigger textile machine for woven fabrics

5)Semi and jumbo jigger machines show how to dye fabric

6) Manual jigger for natural dyes.

Working Principle of JIGGER Dyeing Machine.

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.

Parts of Jigger Dyeing Machine:

The parts of jigger machine are specified as follows: batch roll, hinged cover, fabric unloaded, dye liquor container, guide roller, steam heating coil, main roller, fabric winding, adjustable expander bar, fabric expander bar, dye vat and drain.

Fig: Parts of jigger dyeing machine.

Objectives of JIGGER Dyeing Machine:

1) Dyeing (exhaust) is a chemical process by which textile substrates are immersed in liquor containing dyestuffs and chemicals by which the dyestuffs are transferred to textile substrates in a proper manner. For every shade and batch, quality control (QC) goes shade check, wash fastness, rubbing fastness, water fastness and light fastness, tear test, tensile test, pick-up test, shade listing and tailing.

A dye-trough design ensures minimum possible liquor ratio.

2) Fabric rope monitors control system for precise calculation and control of the fabric speed and tension.

3)Uniform dyeing conditions in the dye trough are independent of the batch size.

Water meter is used to control rinsing.

4) Dosing of dyes and chemicals is dependent on the fabric length passing through the dye bath.

5) The key accessories used are wooden plate, sewing machine, A-frame/ batcher, eye-protecting glass, hand gloves, rotation station, bucket mixer and filter cloth.

Dyeing Process by Jigger Dyeing Machine:

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:

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

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

.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.

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.

Chemical Used in Jigger Dyeing:

Chemicals/materials     Used in average

Used

Wetting agent                 0.25-0.5 g/L

Detergent                         0.5-1 g/L

Dye stuff (reactive,         Differs on the 

sulphur, etc.)                    shade of fabric

Caustic                             1.323 g/L

Soda ash                          5 g/L

Reducing agent               9-10%

Oxidizing agent                2 g/L

Acid                                    2 g/L

Compressed air                As required

Salt                                    20 g/L

Steam, water                    As required

Advantages of Jigger Dyeing Machine:

1) The cloth is dyed in open width form in textile industry

2) The material to liquor ratio is 1:3, which is used for dyed fabric in textile industry

3) Liquor ratio 1:4, which saves huge amount of chemical cost and steam cost

4) Less chemical lose for woven fabric in textile industry

5))No need training to operate how to dye fabric.

Disadvantages of Jigger Dyein Machine:

1) It exerts lot of tension in the warp direction and because of this normally knitted fabrics, woolen, silk, etc., cannot be dyed in jigger dyeing machine because it is only for woven fabric.

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

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

4)The low liquor ratio makes washing-off difficult.

5) 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.

Ref:-https://textilelearner.net