Burning Test of Textile Fiber | Flammability Test of Textile Fiber |Fiber Identification Through Burning Test

Fabric Identification is done with a simple fabric burn test or fiber burn test. Flammability testing, Flammability Test is best to know the identification of fabric.

To recognize the composition of fabrics by the burning test ,the sample of fibre, yarn of fabric should be moved slowly towards a small flame and the reaction to heat carefully observed .One end of the sample should be put directly into flame to determine its burning rate and characteristics. The burning odour should be noted and the characteristics of the ash such as amount ,form, hardness and colour should be examined.

To identify fabric that is unknown, a simple burn test can be done to determine if the fabric is a natural fiber, man made fiber, or a blend of natural and man made fibers. The burn test is used by many fabric stores and designers and takes practice to determine the exact fiber content. However, an inexperienced person can still determine the difference between many fibers to “narrow” the choices down to natural or man made fibers. This elimination process will give information necessary to decide the care of the fabric.

Warning
All fibers will burn! Asbestos treated fibers are, for the most part fire proof. The burning test should be done with caution. Use a small piece of fabric only. Hold the fabric with tweezers, not your fingers. Burn over a metal dish with soda in the bottom or even water in the bottom of the dish. Some fabrics will ignite and melt. The result is burning drips which can adhere to fabric or skin and cause a serious burn.

Identification of Fibers Through  Burning Test:

Cotton
When ignited it burns with a steady flame and smells like burning leaves. The ash left is easily crumbled. Small samples of burning cotton can be blown out as you would a candle.

Linen
Linen takes longer to ignite. The fabric closest to the ash is very brittle. Linen is easily extinguished by blowing on it as you would a candle.

Silk
It is a protein fibre and usually burns readily, not necessarily with a steady flame, and smells like burning hair. The ash is easily crumbled. Silk samples are not as easily extinguished as cotton or linen.

Wool
It is also a protein fibre but is harder to ignite than silk as the individual “hair” fibres are shorter than silk and the weave of the fabrics is generally looser than with silk. The flame is steady but more difficult to keep burning. The smell of burning wool is like burning hair.

Man Made Fibres

Acetate
Acetate burns readily with a flickering flame that cannot be easily extinguished. The burning cellulose drips and leaves a hard ash. The smell is similar to burning wood chips.

Acrylic
Acrylics burn readily due to the fibre content and the lofty, air filled pockets. A match dropped on an acrylic blanket can ignite the fabric which will burn rapidly unless extinguished. The ash is hard. The smell is acrid or harsh.

Nylon
Nylon melts and then burns rapidly if the flame remains on the melted fibre. If you can keep the flame on the melting nylon, it smells like burning plastic.

Polyester
Polyester melts and burns at the same time, the melting, burning ash can bond quickly to any surface it drips on including skin. The smoke from polyester is black with a sweetish smell. The extinguished ash is hard.

Rayon
It is a regenerated cellulose fibre which is almost pure cellulose. Rayon burns rapidly and leaves only a slight ash. The burning smell is close to burning leaves.

Limitation of Burning Test:
It is apparent that many fibers have similar burning reactions that might cause doubt and occasional confusion.

What is Foam Dyeing/Shaving Cream Dyeing? | Foam Dyeing Procedure |Requirements of Foaming Agents

Foam Dyeing

In case of foam dyeing, the main dyeing elements is foam. For that’s this dyeing is called foam dyeing. A fabric is padded with a foam formed from an aqueous solution of a dyestuff, a foaming agent and a carrier for the dyestuff and the padded fabric is maintained at elevated temperatures to fix the dye. The advantages of the process include improved dye prefixation, improved migration of the dye into the fiber, higher color yields in the fabric even after relatively short dyeing times and improved dimensional stability of the dyed fabrics. 

Foam Dyeing

Foam is a dispersion of a gas in a liquid. Here the liquid is generally water and the gas is generally air but it may also be an inert gas. This is familiar as fort on beer shaving foam etc.

Types of Foam:
Broadly there are two types of foam namely
1. Dispersion foam
2. Condensation foam

Materials Need for Foam Dyeing:
- White fabric - cotton, rayon, silk or other natural fiber to dye on
- Dharma Fiber Reactive MX dyes
- Soda Ash Fixer
- Synthrapol
- Squeeze bottles to hold your dyes
- Foam shaving cream, preferably containing aloe
- Flat, shallow, plastic or metal pan
- Plastic mixing bowls
- Wire whisk
-Tape

Requirements of Foaming Agents:

1. It should generate foam readily.
2. It should offer a good wetting capability.
3. It should exert fast an uniform wetting action.
4. It should show little or no effect on color fastness.
5. It should be compatible with other products of the finishing mix.
6. It should be least effect ed by water hardness.
7. It should not cause yellowing of white materials.
8. It should be easily stabilized.
9. It should be capable of producing various bubble sizes to meet specific requirements.

Foam Dyeing Procedure:

1. Pre-wash the fabric in Synthrapol. This removes any oils or dirt that might be on the fabric and gives you better dye results.

2. Dissolve one cup soda ash in one gallon of hot water. Soak the fabric in the soda ash solution for 5-10 minutes, wring lightly and hang dry.

3. Dissolve your dye powders (2 tsps. for colors without an *, 4 tsps. for colors with one *, 8 tsps. for colors with two *) in a small amount of warm water, stirring into a smooth paste. Stir in 1/2 cup lukewarm water. For reds and colors containing red, filter the dye solution through a coffee filter or piece of silk to remove difficult to dissolve particles. Add 1/2 cup shaving cream to the filtered dye solution, then pour this mixture into the squeeze bottle.

4. Dilute about half a can of shaving cream with a cup of water in a large mixing bowl. Whisk the mixture until well blended and thick and creamy. Pour mixture into the tray until about an inch deep.

5. Squirt the dye/shaving cream mixture over the shaving cream/water mixture in the tray in any pattern you wish. Use a comb, chopsticks, or any tool to swirl and spread the dye into any pattern desired.

6. Place a piece of the prepared fabric on the surface of the shaving cream and dye pattern. Remove any air bubbles by pushing down gently with a tool or a gloved hand.

7. Allow the fabric to sit on the surface of the dye/shaving cream for 5 minutes, then remove fabric by lifting carefully. Place on a flat surface shaving cream side up and allow to sit for 2 to 24 hours to develop the dye. The piece needs to remain moist for the activation to take place.

8. Rinse fabric in cool running water to remove the soda ash, and then increase temperature to hot. Continue to rinse until water is almost clear, then wash in hot water and Synthrapol to remove any excess dye. Dry, press and voila!

Presentation of Fashion Show | Historical Background of Fashion Show

Fashion Show

Fashion Show
A fashion show is an event put on by a fashion designer to showcase his or her upcoming line of clothing. In a typical fashion show, models walk the catwalk dressed in the clothing created by the designer. Occasionally, fashion shows take the form of installations, where the models are static, standing or sitting in a constructed environment. The order in which each model walks out wearing a specific outfit is usually planned in accordance to the statement that the designer wants to make about his or her collection.

The way that each outfit is presented on the catwalk isn’t necessarily the way the designer is trying to make people wear his or her creations in everyday life. In this instances, this is more of an intellectual/artistic construction of the designer for the same purpose of making a statement or presenting a particular idea. It is then up to the audience to not only try to understand what the designer is trying to say by the way the collection is being presented, but to also visually de-construct each outfit and try to appreciate the detail and craftsmanship of every single piece. A wide range of contemporary designers tend to produce their shows as theatrical productions with elaborate sets and added elements such as live music or a variety of technological component like holograms, for example

History of Fashion Show
Because “the topic of fashion shows remains to find its historian,”the earliest history of fashion shows remains obscure. In the 1800s, “fashion parades” periodically took place in Paris couture salons.

American retailers imported the concept of the fashion show in the early 1900s.The first American fashion show likely took place in 1903 in the New York City store Ehrlich Brothers.By 1910, large department stores such as Wanmakers in New York City and Philadelphia were also staging fashion shows. These events showed couture gowns from Paris or the store’s copies of them; they aimed to demonstrate the owners’ good taste and capture the attention of female shoppers.By the 1920s, retailers across the United States held fashion shows.Often, these shows were theatrical, presented with narratives, and organized around a theme (e.g. Parisian, Chinese, or Russian).These shows enjoyed huge popularity through mid-century, sometimes attracting thousands of customers and gawkers.

In the 1970s and 1980s, American designers began to hold their own fashion shows in private spaces apart from such retailers. In the early 1990s, however, many in the fashion world began to rethink this strategy. After several mishaps during shows in small, unsafe locations, “the general sentiment was, ‘We love fashion but we don’t want to die for it,’” recalls Fern Mallis, then executive director of the Council of fashion designers of American. In response to these shows, the New York shows were centralized in Brayn Park during fashion week in late 1993. Lately from the 2000 to today, fashion shows are usually also filmed and appear on specially assigned television channels or even in documentaries.

Engrave Roller Printing | Working Procdure of Roller Printing |Advantages/Disadvantages of Engrave Roller Printing Machine

Engrave Roller Printing
Roller Printing also called engrave roller printing. It is a modern continuous printing technique. In this method, a heavy copper cylinder (roller) is engraved with the print design by carving the design into the copper. Copper is soft, so once the design is engraved, the roller is electroplated with chrome for durability. This printing technique developed in the late 19th and early 20th centuries. Until the development of rotary screen printing; it was the only continuous technique. Designs with up to 16 colors present no problem in Roller Printing.

Main parts of Roller Printing

1.  Color doctor
2.  Lint doctor
3.  Blankets
4.  Back grey
5.  Furnishers
6. Color box / tray
7.  Color unit

Roller Printing Machine

Working Process of Roller Printing:

This machine has a main cylinder that is fitted with a large gear.In this printing, the print paste is supplied from reservoirs to rotating copper rollers, which are engraved with the desired design. These rollers contact a main cylinder roller that transports the fabric. By contacting the rollers and the fabric the design is transferred to the fabric. As many as 16 rollers can be available per print machine, each roller imprints one repeat of the design. As the roller spins, a doctor blade in continuous mode scrapes the excess of paste back to the colour trough. At the end of each batch the paste reservoirs are manually emptied into appropriate printing paste batch containers and squeezed out. The belt and the printing gear (roller brushes or doctor blades, squeegees and ladles) are cleaned up with water.

The Defects in the Engrave Roller Printing

1.  Scratches
2.  Snappers
3.  Lifts
4.  Streaks
5.  Scumming
6.  Lobbing

Advantages of Engrave Roller Printing Machine

1.  Higher production without rotary screen printing machine.
2.  14 colors can be used for printing.
3.  Medium design can be produced.
4.  Can be used for printing any style.
5.  Any color is used for printing without higher alkali or conc. acid.
6.  Repeats do not exist as printing is continuous.
7.  Higher production by using single color.
8.  Complex design is possible.

Disadvantages of Engrave Roller Printing Machine

1.  Large design is not possible.
2.  Generally, shedding fault is found.
3.  Higher coloring effect is not possible as like block printing.
4.  Lower production by using more than one color.
5.  Changing time is high. 
6.  Engraving the printing roller is expensive Operation

Difference between Rotary screen printing and Copper screen printing

The Knitting Action of the Latch Needle | How to Latch Needle Works?

FigA. Knitting action of the latch needle.

Figure A shows the position of a latch needle as it passes through the cam system,completing one knitting cycle or course as it moves up and in its trick or slot.

1 The rest position. The head of the needle hook is level with the top of the verge of the trick. The loop formed at the previous feeder is in the closed hook. It is prevented from rising as the needle rises, by holding-down sinkers or web holders that move forward between the needles to hold down the sinker loops.

2 Latch opening. As the needle butt passes up the incline of the clearing cam, the old loop, which is held down by the sinker, slides inside the hook and contacts the latch, turning and opening it.

3 Clearing height. When the needle reaches the top of the cam, the old loop is cleared from the hook and latch spoon on to the stem. At this point the feeder guide plate acts as a guard to prevent the latch from closing the empty hook.

4 Yarn feeding and latch closing. The needle starts to descend the stitch cam so that its latch is below the verge, with the old loop moving under it. At this point the new yarn is fed through a hole in the feeder guide to the descending needle hook, as there is no danger of the yarn being fed below the latch. The old loop contacts the underside of the latch, causing it to close on to the hook.

5 Knocking-over and loop length formation. As the head of the needle descends below the top of the trick, the old loop slides off the needle and the new loop is drawn through it. The continued descent of the needle draws the loop length, which is approximately twice the distance the head of the needle descends, below the surface of the sinker or trick-plate supporting the sinker loop. The distance is determined by the depth setting of the stitch cam, which can be adjusted.

The rest position actually occurs between positions 1 and 2, when the open needle hook just protrudes above the needle trick verge. In this position, a feeder would be passed without the needle receiving a new loop and the old loop would not be cast off, so that a float stitch would be produced. The tucking in the hook position occurs between positions 2 and 3, when the needle can receive the new yarn but the old loop has not been cleared from the open latch.

The latch needle used on the Stoll CMS V-bed flat machine has a spring-loaded latch so that it fully opens and fully closes. Also, the latch spoon does not project beyond the needle head. Loops thus slide easily over the hook and latch, the yarn is less likely to be split, and there is greater security for the knitted loops.

NB: Although the above knitting action is described assuming the needle to be moving through the knitted loops, the movement is relative and the same effect can be achieved by moving the loops over a stationary needle.