Garment Dyeing | How to Garment Dyeing? | Why Garment Dyeing? | GarmentDyeing Machines

Garment Dyeing

Garment dyeing is the process of dyeing fully fashioned garments (such as pants, pullovers, t-shirts, jeans, sweaters, dresses, bathrobes, casual jackets, shirts, skirts, hosieries) subsequent to manufacturing, as opposed to the conventional method of manufacturing garments from pre-dyed fabrics. Most garments are made of cotton knit goods and/or cotton woven fabrics.

Although several other fabrics can be found in the whole or in part such as wool, nylon, silk, acrylic, polyester and others. Due to cost savings and fashion trends, garment dyeing has been gaining importance and popularity in the past years and will continue to do so in the future.

Why Garment Dyeing?
Traditionally, garments are constructed from fabrics that are pre-dyed (piece dyed) before the actual cutting and sewing. The advantage of this process is the cost effectiveness of mass producing identical garments of particular colors. A major drawback with this approach is the risk associated with carrying a large inventory of a particular style or color in today’s dynamic market.

Garment Dyeing Machines
Paddle machines and rotary drums are the two types of equipment regularly used for garment dyeing. Rotary drum machines are sometimes preferred for garments, which require gentler handling, such as sweaters. A high liquor ratio is required for paddle machines, which is less economical and may limit shade reproducibility. Many machinery companies have developed sophisticated rotary dyeing machines, which incorporate state-of-the-art technology. Following machines are generally used for garment dyeing

Garment Dyeing Machines

1.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.

In 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 are normally dyed using PP/PET bags.

2.Rotary Drum Dyeing Machines
These machines work on the principle of “movement of textile material and a stationary liquor”.The rotary drum dyeing machine consists of rotating perforated cylindrical drum , which rotates slowly inside a vessel of slightly bigger in size. The internal drum is divided into compartments to ensure rotation of goods with the drum rotation, and the outer vessel holds the required quantity of dye liquor. High temperature drum machines are capable of processing the garments up to 140o C.

Features of modern rotary-dyeing equipment include the following:
1. lower liquor ratio
2. gentle movement of goods and liquor (minimizes surface abrasion)
3. rapid heating and cooling
4. centrifugal extraction
5. variable drum speed with reversal capability (adaptable to a wide variety of goods)
6. continuous circulation of goods (improves migration control)
7. easy of sampling
8. variable water levels with overflow rinsing capabilities
9. large diameter feed and discharge lines (minimizes filling and draining time)
10. microprocessor controls
11. lint filters
12. pressure dyeing
13. auto-balancing drums

One feature that can be used to reduce abrasion on delicate garments or to minimize tangling is a compartmental chamber, sometimes referred to as a “Y” pocke .The rotary drum machines are very simple to operate and are quite compact in size. The cost of unit is also not high .

Drum dyeing-centrifuging machines are also called “multipurpose drum machines” or “multi-rapid dyeing centrifuging machines” since these machines can perform scouring, dyeing, centrifuging and conditioning successively with automated controls. The goods are treated in a perforated inner drum housed within an outer drum (dyeing tank). Inner drums without dividing walls are provided with ribs that carry the goods along for a certain time, partially lifting them up out of the liquor. These machines can operate at very low liquor ratios and can dye the goods up to 98 -140o C. This is suitable for knits as well as other garments. Liquor circulation can be intensified using additional jets. Drums can be rotated in both the directions.

3. Tumbler Dyeing Machines
These machines are being used for small garments either in loose form or in open mesh bags. Design wise the tumbler dyeing machines are similar to the commercial laundering machines.

The principle of operation is to load the material into perforated inner SS tanks , which rotates round a horizontal shaft fixed at the back of the drum. The drum is divided into compartments for moving the goods with rotation of drum. A variety of tumbling machines have higher rotation speeds and can spin dry at the end of the cycle. These are similar to dry-cleaning machines.

Rotating drum machines are more efficient and cleaner to operate than paddle machines. The more vigorous mechanical action often promotes more shrinkage and bulking, which may be desirable for some articles. In order to handle higher quantities and large production of similar pieces the latest machines are provided with several automatic features and sophistication.

4.Toroid Dyeing Machines

Toroid Dyeing Machines

In these machines the garments circulate in the liquor in a toroidal path with the aid of an impeller situated below the perforated false bottom of the vessel. Movement of the goods depends completely on the pumped action of the liquor. High-temperature versions of this machine operating at 120 to 130°C were developed in the 1970s for dyeing fully-fashioned polyester or triacetate garments. The liquor ratio of such machines is about 30:1.

5.The Gyrobox
The machine has support in the form of a large wheel, which is divided into 12 independent non radial compartments. The goods are placed in these compartments .The wheel runs at a moderate speed of 2-6 rpm.The main advantage of this machine are,

1.Reduced M:L
2.Different types of garments can be dyed simulteneously .
3.Flexible loading
4.Fully automatic operation.
6.The MCS Readymade garment dyeing machine

The rotodye machines are suitable for dyeing pure cotton,wool,polyester,cotton blends in the form of T shirts, sweaters, bath rugs and accessories , socks and stockings.

6.Modified Pegg Toroid Whiteley Garment Dyeing Machine
This is an improved version of Toroid machines , the additional features are

1.The machine is suitable for both atmospheric and pressure dyeing.
2.Full automation upto hydroextraction.
3.The design features,speed and performance is simplified to make the machine more versatile and free from operating problems.

Advantages of Garment Dyeing

1. Handling of smaller lots economically
2. Enables various special effects to achieved
3. Distressed look can be effectively imparted
4. Unsold light shades can be converted into medium and deep shades

By the time the garment has been in a boiling dyebath and then tumble-dried, it will have adopted its lowest energy state and will not suffer further shrinkage under consumer washing conditions

Latest fashion trends can be effectively incorporated through garment wet processing by immediate feedback from the customer

Disadvantages of Garment Dyeing

1. High cost of processing
2. A little complicated dyeing

Garment accessories like zips, buttons, etc impose restrictions. The garments produced from woven fabrics create many problems and it has been found that the existing textile treatment styles as developed for piece dyed fabric cannot be just assembled for garment wet processing operation such as garment dyeing, unless they have been engineered from the original design stage for garment dyeing.

The factors governing processing of ready-made garments are
• Sewing Thread
• Metal Components. Shrink behavior
• Accessories
• Foreign substances
• Interlining
• Care labeling.

Analysis of Diamond Woven Fabric Structure | Specification of DiamondWoven Fabric

Experiment name: Analysis of woven fabric(Diamond).

Object:
1.To sketch the structure of fabric.
2.To know about the raw material of fabric.
3.To know about different specifications of fabric.

Sample: 

 

Apparatus:
1. Counting glass,
2. Needle,
3. Beesleys balance,
4. Twist tester,
5. GSM cutter,
6. Graph paper.

Analysis:
1. Weave plan: In graph the gaps between the lines are considered according to X axis as weft threads and according to Y axis as warp threads. The up threads are indicated by filling up the gaps and down threads without filling up the gaps.

2. Drafting plan: According to British system drafting plan is drawn at the top of weave plan. Here pointed draft is used to draft the plan.

3. Lifting plan: The lifting plan is drawn at the right side of the weave plan.

4. Face side and backside: The face and backside can be easily understood.

5. Direction of warp and weft: Direction of both warp and weft are indicated by arrow marks by the side of the sample.

6. Raw material: Both warp and weft yarns are cotton.

7. Thread density:

No. of reading	EPI	Average	PPI	Average
1	56	54	39	40
2	55		40
3	53		37
4	54		38
5	52		41

8. Yarn count:

No. of reading	Warp count	Average	Weft count	Average
1	18	20	7	9
2	19		10
3	21		9
4	20		8
5	22		11

9. Yarn twist:

No. of reading	Warp twist	Average	Weft twist	Average
1	3	4	3	5
2	5		6
3	4		4
4	3		5
5	6		6

10. Direction of twist: Both warp and weft yarns are ‘Z’ twisted.
11. Design of fabric: The formula number of this fabric is .

12. GSM calculation: We take one square inch fabric sample and find its weight 0.1116 gm.
We know 1 inch = 2.54 cm i.e. 0.0254 m. So, 1 sq. inch = 0.02542 sq. m.
Now, 0.02542 sq. m sample wt. = 0.1116 gm.
1 sq. m sample wt. = 173 gm.
Therefore GSM of fabric is 267 gm/meter2.

13. Repeat size: The repeat size of this fabric is 18´18.

14. Type of loom: Tappet loom is used to produce this fabric.

End Use:  

This type of fabric is used for making towel, bedsheet, pillow cover, table cloth and so on.

Conclusion: 

Analysis of fabric structure is very essential to know about the fabric. Because it gives all kinds of information about the fabric that is needed to reproduce or to change structure or design of fabric. By this practical I learn how to analyse primarily a simple plain structure of woven fabric.

Block Printing Style | Procedure of Block Printing on Fabric | AfterTreatment of Block Printing

Block Printing

The printing of fabric by hand, using carved wooden or linoleum blocks, as distinguished from printing by screens or roller is called block printing. Block printing is a special form of printing first developed in China. The earliest known example with an actual date is a copy of the Diamond Sutra from 868 A.D (currently in the British Museum), though the practice of block printing is probably about two thousand years old.

Procedure of Block Printing 

The fabric to be printed is washed free of starch and soft bleached if the natural gray of the fabric is not desired. If dyeing is required as in the case of saris where borders or the body is tied and dyed it is done before printing. The fabric is again washed to remove excess dye and dried thoroughly. The fabric is stretched over the printing table and fastened with small pins. This is an important stage as there should be a uniform tension in the fabric and no ripples. Color is mixed separately in another room. Usually pigment dyes are used for cotton.

The first step in block printing is the production of the original document. This is laid on a large, smooth wooden block and fixed into place, reversed. Next, craftsmen of various skill levels, ranging from master carvers for the fine work to less talented artisans for cheaper blocks or less important sections, carve the original painted, drawn or written image into the block of wood. The block can now be covered with ink and used in a press to create duplicates of the original. 

Color paste must be applied to the block surface in a controlled manner, and this was achieved by using a ‘sieve’. A small tub was nearly filled with a starch paste and a waterproof fabric, stretched on a frame, rested on the paste. A piece of woolen fabric was stretched on a slightly smaller frame and fastened to make the sieve. The sieve as saturated with color paste and placed on the waterproof fabric. For each impression, the ‘tiered’ (a boy) spread the color paste on the top surface of the woolen sieve with a large brush and the printer charged the block by pressing it on the wool. The block was then carefully positioned on the fabric, using the pitch pins as guides, and struck with a mallet. After printing a table length with the first block, the second was printed and then any others required to complete the design. 

After Treatment of Block Printing
The fabric, after printing is dried out in the sun. This is part of the fixing process or aftertreatment of printing. It is then rolled in wads of newspapers to prevent the dye from adhering to other layers and steamed in boilers constructed for the purpose. Silks are also steamed this way after printing. After steaming, the material is washed thoroughly in large quantities of water and dried in the sun, after which it is finished by ironing out single layers, which fix the color permanently.

Step Cleaner/Ultra Cleaner/Super Cleaner | Object of Step/ Ultra/ SuperCleaner Machine

Step cleaner machine is an inportant machine in ring spinning for cleaning and opening impurities from cotton. This machine is set normally after porcupine opener machine.

Object of Step/ ultra/Super Cleaner Machine
i. To open & clear the cotton by combinations of opposite spike action & the beating action.
ii. To remove the impurities such as leaves, stalk, motes & sand without damage the fiber.

Main Parts :
i. Motor.
ii. Motor pulley.
iii. Beaters.
iv. Baffle plate.
v. Grid.

Step Cleaner

Main Setting Point :
Set to do the require amount as cleaning close grid bars, setting gives good opening & large grid bar setting gives poor opening, other setting points are, Beater to Grid bar = 1“ & beater to beater = 8“.

Specification :

i. Motor r.p.m = 695

ii. Dia of the beater = 18.6“

iii. Dia of two pulley = 21.2“

iv. Dia of one pulley = 16“

v. No. of striker = 26

Calculation :

          Beater r.p.m = 695*(16“/21.2“)

                                   = 524.5

          Beater per min. = 524.5*26

                               = 13637

Conclusion :
This is the second m/c of blow room line. It works step by step & for this it is called step cleaner. It is a good instrument of opening & cleaning of cotton by the action of beater. It also removes ascertain a out of leaves, stalk & other impurities. It is suitable for process of low grade cotton.