WELCOME TO OUR PRESENTATION

Presented By:Group name: ShadowGroup members:1. Mahtab Uddin Ahmed Likhon ID:121-285-0-452. Radeef Mujahid (L) ID:121-277-0-453. Anisul Haque ID:121-301-0-454. Ishtiaq Ahmed ID:121-288-0-455. Moniruzzaman Shawon ID:121-290-0-456. Md. Mahmudur Rahman ID:121-271-0-457. Md. Mushfiqur Rahman ID:121-276-0-458. Aminul Islam ID:121-289-0-45

PresentationOn

“Dry Finishing or Dry Process on Denim”

Denim:Denim is a sturdy cotton twill textile in which the weft passes under two or more warp threads. This twill weaving produces the familiar diagonal ribbing of the denim that distinguishes it from cotton duck.

It is a characteristic of any indigo denim that only the warp threads are dyed, whereas the weft threads remain plain white. As a result of the warp-faced twill weaving, one side of the textile then shows the blue warp threads and the other side shows the white weft threads. This is why blue jeans are white on the inside. This type of dyeing also creates denim's fading characteristics, which are unique compared to every other textile.

Etymology and origin:The word "denim" comes from the name of a fabric that was first made in the city of Nîmes, France, by the André family. It was originally called serge de Nîmes but the name was soon shortened to "denim."

Denim has been used in the United States since the late 18th century.

Denim was traditionally colored blue with indigo dye to make blue jeans, although "jean" formerly denoted a different, lighter, cotton fabric. The contemporary use of the word "jean" comes from the French word for Genoa, Italy (Gênes), where the first denim trousers were made.

CHARACTERISTICS OF DENIM FABRIC:

• It is for long wearing.

• It is hard wearing.

• It is very strong and durable.

• It resists snags and tears

• It creases easily.

GARMENT WASHING:The technology which is used to modify the appearance, outlook comfort ability & fashion of the garments is called garment washing.

Since 1978, garments pre washing has become more and more popular. It began with denim jeans for the following reasons,

Before garments pre washing was done on jeans, consumers had to wash them at home before wearing them because before washing they were too stiff, too long and too big to wear.

After pre washing, the consumers do not have to worry about the fit after they wash them as pre washing has taken away almost all the shrinkage and made the jeans stable.

After pre washing the denim color looks livelier particular with the pronounced washed look left on the double needled seams.

Types of finishing/wash process: Wet wash process Dry wash process

Types of Dry wash process:

1. Sand Blasting

2. Hands scraping

3. Overall wrinkles & Permanent wrinkle

4. Grinding &Destroy

5. Tacking or Tag Pinning

6. PP Spray & PP Sponging

7. Crinkle

8. Whisker

9. Chevron , Knee Star, Hot Spot

10. Resin

11. Ripping, Pilling and Cuts

12. Patch & Repairs along with Bleach Spots

1. Sample washing Machine (Horizontal / Vertical Type)2. Washing Machine (Side loading)3. Washing Machine (Front loading)4. Hydro extractor Machine5. Dryer Machine (Steam)6. Dryer Machine (Gas)7. Chemical Mixture Machine8. Industrial Oven (Gas/Electric)9. Boiler10. Submersible Pump

11. Grinding Machine12. Tagging Machine13. Steam chamber for crinkle14. E.T.P (Effluent Treatment Plant)15. Generator16. Sand Blasting Gun17. Sand Blasting chamber18. Spray gun and dummy19. Screw compressor20. Laser draw

TYPE OF MACHINE USED IN WASHING PLANT:

1. Enzyme2. Detergent3. Acetic Acid4. Anti-stain5. Bleaching powder6. Sodium hyposulfite7. Caustic Soda8. Soda Ash9. Sodium Bicarbonate10. Potassium Permanganate11. Flax softener12. Micro Emulsion Silicon

13. Salt (sodium chloride)14. Buffer15. Hydrogen peroxide16. Stabilizer17. Fixing18. Catanizer19. Optical Brightener20. Resin21. Sodium Metabisulphite

TYPES OF CHEMICAL USE IN WASHING PLANT:

1. Sand Blasting: Sand blasting is the process of scrubbing off the garment by blowing high speed air mixed with very fine particles of sand. This is a very successful and most widely used process for fashion articles. When the surface area of the garment is blasted, white cotton appears beneath the blasted area and the effect is appeared very similar to the worn out jeans.

Different types of dry washing process on denim:

2. Sand Blasting With Sand Paper:Sand ballasting with paper, commonly known as scrapping is the most widely used process for creating blasting effect. It is usually done by mounting the garment on rubber balloons. After mounting the garment air balloon is filed with air to expose the area to operator. It is important to fill the pressure.

Area of Application:Specified areas for sand blasting are front thigh, back seat, back panel near bottom or front panel around knee. Sometime full body blasting is also done for giving a unique look to fabric. Hot spots may be designed for more real look on front knees or back seat by intense blasting in these areas.

3. Hands scraping:A hand scraper is a single-edged tool used to scrape metal from a surface. This may be required where a surface needs to be trued, corrected for fit to a mating part, needs to retain oil (usually on a freshly ground surface), or even to give a decorative finish.

Surface plates were traditionally made by scraping. Three raw cast surface plates, a flat scraper and a quantities of bearing blue (6) (or Red Lead) were all that was required in the way of tools.

The scraper in the center of the image is a three corner scraper and is typically used to debar holes or the internal surface of bush type bearings. Bushes are typically made from bronze or a white metal.

4. Wrinkle:A wrinkle, also known as a rhytide, is a fold, ridge or crease in the cloth or garments. Wrinkle is a particular type of pressure in the finished fabric. It is produced during finishing operations by the thickness of the seam used to join pieces for processing. Wrinkle resistance in a fabric is a desirable attribute, but it is not easily measured quantitatively. Wrinkle resistance varies from quite low in many fabrics to very high in resilient fabrics. In order to form a wrinkle, a fabric’s wrinkle resistance must be overcome. The fabric may, however, produce strains and store potential energy that can become evident as wrinkle recovery under suitable conditions.

i. Permanent Wrinkle Process:Permanent wrinkle is doing on garments after all types of wet process wash in dry position. Permanent wrinkle is done on the garments made from

all types of fabrics like, Denim, Twill, Canvas, Poplin, Corduroy, Knit & Polyester etc. For permanent wrinkle we are use resin which is spray

on garments particular/specific area by nozzle. Resin is diluted with water which is recommended by

chemical supplier, generally 20% resin& 80% water. Then trolley with resin treatment garments put

inside the Industrial oven. Set temperature 140°c to 160°c, Time 20-40

minutes.

ii. Overall Wrinkle Process: Generally overall wrinkle is doing on garments

after all types of wet process & dry process. Overall wrinkle is done on the garment made from

all types of fabrics like, Denim, Twill, Canvas, Poplin, Corduroy, Knit, Polyester, Viscose

& Nylon etc. Now tie the whole garment in tight position by

thread. For overall wrinkle, we are used resin in washing

machine with water and run tied garments for 5 to 10 minutes at 50°c temperature.

5. Grinding &Destroy:Edge distressing or grinding is the process of destruction on jeans form edges of the garment. When we look at old jeans we find it destroyed from the edges of pockets, fly area, belt and bottom. This used effect can be created on jeans by grinding and is of key importance in high fashion garments. Grinding is done of garments by pen type of stone tools. It can be done in mid of the wash process. In many workshops it is done before any wash process as first process after stitching. Stone tools similar to grinders used in wood and stone industry are utilized to work on garments with a few amendments to their design.

6. Tacking or Tag Pinning:Tacking or more commonly tag pinning is a very in fashion style in denim garment in these days. In this process the effect is created by swift tag machines with the help of plastic or nylon tag pins in rigid form of garment to get contrast.

Usually tag pin machines are used to attach tag pins to garment. The procedure is very simple and proceeds as; garment is folded on required area and tacked through folds. Number of folds can be two to four or five in regular in tacking. These tag guns are not especially designed for heavy folds like we do in tacking so durability of the gun is a consistent problem. Also broken needles of tag gun are issue for both operator and consumer. Automated tacking machines are used more successfully in some units. These machines are bit expensive but are far more efficient and secure than tag guns.

Area of Application:This effect can be designed anywhere on the garment in different styles. Most favorite areas for tacking are on waistband, bottom hems, back pocket and front pocket corners etc.

On front or back sides of garment, tacking can also designed horizontal of vertical patterns on full length panel.

7.P P Spray & P P Sponging: Potassium permanganate spray is done on jeans to take a bright effect on sand blast area. One important thing about potassium permanganate spray is, this is usually a sporting process to increase the effect of sand blast. Potassium permanganate solution is sprayed on blasted area of jeans garment with the help of normal spray gun. This potassium permanganate spray appears pink on garment when fresh and turns to muddy brown on drying. The garment is hanged in open to dry after potassium permanganate spray and when the potassium permanganate turns its colors completely then it is considered to ready for next process.

It is always followed by neutralization process. Sodium Meta bisulphate is most commonly used neutralizer. A number of products are available in market for neutralization process like sodium Meta bisulfate selected on the bases of effect required on blasted area.

The variables in spray process:Garments are mounted on air filled rubber dummies and chemical is sprayed on blasted areas. The variables in spray process are as follow-

1. Distance of spray gun to garment- less distance will give more defined and sharp effect where as distant spray will result to more mild and merged effect. Distance ranges from one foot to two and a half foot.

2. Air to Water Ratio of Gun- this is to be set very carefully. Low air pressure possibly will through KMnO4 drops on garment resulting to bright white spots whereas high pressure will produce very low bright effect spray effect to areas where it is not required.

3. Potassium Permanganate Solution Concentration- of course, this will control the extent to brightness.

8. Whisker:Mustaches or whiskers are one of the most important design of a used look garment. The idea of whiskers is taken form the worn out lines and impression patterns generated by natural wearing on hips and front thigh area. On old jeans, a number of patterns can be finding consequential to fabric, body shape of user or sitting posture.

Various methods are designed to create this impression on jeans. Mostly rubber balloons are available with different pattern designs. Garments are mounted on balloons and filled with air to get impressions of whiskers. Garment is scrubbed over pattern carefully with sand paper on engraved pattern lines. This operation requires high skilled labor and who can handle uniformity and sequence in whisker line. Fabric may damage during rubbing if care is not taken. But this method is more successful in industries where the production is consistent to articles i.e similar articles are produced in large quantities. This method is famous for high quality and cost effectiveness.

9. Chevron, Knee Star, Hot Spot:On Denim, whiskers / Mustaches, Chevrons are nothing but the worn out lines / impression generated by natural wearing on hip & thigh area. There are many designs & pattern available.

This is being done manually with help of sharp edge Emery paper rolled on fine wood stick or pasted on plastic material. Before starting execution placements & pattern must be marked on garments, this will help operator to execute the pattern right to match the aesthetics of garment.

Hot spots are heavy/intense area on thigh or knee which is made purposely to create used look & on knee area if any whiskers line are there, called knee star.

All above operations are carried out in width direction hence its appears intense than hand sand with less strokes, because hand sand is carried out in length direction.

10. Resin: Resin (Formaldehyde free) being used for achieving 3D effect (3 Dimensional), Rigid Look etc. This process can be done by spraying or dipping the garments in to Resin, Catalyst, Silicone & PU solution in right combination according to the fabric strength & desired effect needed. After application of resin solution in right proportion, make manual designing as needed on the thigh, hip & back knee area to get 3Dimentional effect. After making it, it should be manually dried with hot press or hair dryer & then must be cured in oven at right temperature, time as mentioned in resin product manual.

If resin not cured properly, 3 D effect will not be permanent & can cause skin irritation/rashes to the wearer. Highly skilled operators need to execute this process in order to get consistency & uniformity.

11. Ripping, Pilling and Cuts:These effects are created where to copy a real worn out and roughly used jeans. These are created by using sharp edge tool line clippers, blades and knives.

Warp yarn is cut by knife and the white weft yarn is left in place to create a beautiful worn out effect. The garment with cuts is then washed in washers to reveal the white the white thread. This makes the horizontal white lines of weft and if some dye is added to wash bath it will add more beauty to the garment. The secret is the cuts are always kept weft wise i.e in horizontal to the garment. This will keep the weft in place and warp will be removed in washing process. If it let the warp is cut then the only thing you get after wash is a big hole.

Closure:The scope of denim dry finishing is very broad. Only innovative products will be able to open up new markets and new horizons for denim industry. To achieve this it is essential to invest in further research and development. Globalization has opened the door to competition at the highest level. Every industry should now produce products that are best in terms of quality and price. Customers today have a wide range of choices and the one who produces the best quality at a high competitive price will survive and prosper. The driving force for change in denim dry finishes is the need for a competitive strategy by cost conscious finisher to add the value. Compatibility is essential to provide short multifunctional finishes that can be applied simultaneously. Innovative and enhanced results are possible through application of various types of denim finishing, which in turn would bring greater financial profits. To achieve this, the garment manufacturers are required to develop a futuristic vision and take appropriate measures to overcome the problems of denim processing.

Reference:1. http://en.wikipedia.org/wiki/Denim#cite_note-autogenerated1-1

2. http://en.wikipedia.org/wiki/Cotton_duck

3. http://en.wikipedia.org/wiki/Indigo_dye

4. http://en.wikipedia.org/wiki/N%C3%AEmes

5. http://en.wikipedia.org/wiki/Denim#cite_note-autogenerated1-1

6. http://en.wikipedia.org/wiki/Engineer%27s_blue

7. "How jeans conquered the world". BBC News. 2012-02-28.

8. In 1789 George Washington toured a Beverly, Massachusetts factory producing machine-woven cotton denim. (Massachusetts Foundation for the Humanities: Mass Moments

9. Coe, Nick. "The Essential Raw Denim Breakdown – Our 100th Article!". RawrDenim.com. Edmonton, Alberta, Canada: RawrDenim.com. Retrieved 2012-03-28. "I had read somewhere that a pair of raw denim is like an individualized canvass. Indeed the fade results and any other visible marks, rips, or tears are specific you and your body. For a dramatic illustration of what we mean, hop over to Takayuki Akashi's documentary on the “Traveling Denim“."

10. Slater, Sean. "When Should I Wash My Raw Jeans? – A Rough Guide". RawrDenim.com. Edmonton, Alberta, Canada: RawrDenim.com. Retrieved 2012-03-28. "If you’re able to wear your jeans all day, every day then 6 months may be long enough (or perhaps even too long).

11. "Denim Dialogues, Vol. II: Making Them Your Own". Handlebar Magazine. 2011-09-12. Retrieved 2012-12-01.

12. "Jeansbeetles.com". Retrieved 2010-08-04.

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