Presentation On:

“ Dry Finishing On Denim ”

Course: Industrial Garments Wash

Code: GMT 127 

Date of Submission: 07-07-2014

Submitted to

Engr. Chanchal Kumar Kundu

B.Sc. (Textile tech), CTT, DU, BUTexM.Sc (Textile Mgt.), M.Sc (Textile tech) UB, Sweden

Senior Assistant ProfessorBGMEA University of Fashion and Technology

BUFT

Submitted By:

Fahad Islam 121-244-0-45

Batch: 121Section : AMT-2

Dept. of Apparel Manufacturing and Technology

BGMEA University of Fashion and Technology

Acknowledgement  

We are thankful to these following persons for their kind help to make our assignment successfully by providing us information to sample.

 1) Kumar Debnath Sajol

Director (Marketing)Asian Global Sourcing Ltd. (AGS)

Kumar@Asianglobalbd.NetH# 2/A, 3rd Floor, Rd# 2/B, Sonargaon Janapath Road

Sec# 11, Uttara, Dhaka-1230 

2) Mohammad Abdus SalamMerchandiserUpdate Group

Abdussalam@Updategroupbd.ComTower Hamlet (10th Floor)16, Kamal Ataturk Avenue

Banani, Dhaka

Introduction

Garment finishing is one the process applied on garment in order to get a desired look or appearance of the garment, with the introduction of new technologies and equipment it has been fairly easy to obtain desired shades and results.

For finishing of denim fabrics, a range of techniques are used. They all are projected at new possible effects of fabric appearance, namely mill wash or rinse wash, moon wash, over dyed-look, stone wash , sand wash ,bleach, damaged-look, scrubbed look , sand-blast, PP spray , whisker Effect , 3D effects and etc.

Especially, the dry finishing creates many effects on denim fabric, it stimulates the customers to buy and also enhances the market potential of the denim market.

We can say that dry finishing has taken denim to the next level, the next generation denim.

Denim:

Denim has always been on everyone’s wish list, especially faded.

Because of its toughness, style and less care required. Also, now a days governed by the shades or finishes offered by different buyers.

As a result a lot of effort is being put to cater with different shades with less hazardous techniques employed and high productivity.

Denim

Dry Finishing:

The distressed denim that we see around everywhere undergo a wide variety of wet as well as dry treatments to get the desired effects.

Destroying denims is as much an art as it is a technique. The direction in fashion is varied across all areas particularly in denim dry finishing, whether worn or torn to wrinkled or pressed, these trends can appeal to a wide range of consumers.

These can be achieved by variety of denim dry processing technique, which are mainly dependent on physical and on chemical abrasion of the surface dye there by producing different wash-down looks to the denim fabrics.

Types

HAND BRUSH WHISKER 3D WHISKER CRINKLE 3D WRINKLE CHEVRON PATCH

GRINDING RESIN

HEM GRINDING TACKING NICKING PP SPRAY LASER FADDING CURING

Hand Scraping:

Hand scraping is step which is generally being done in rigid form of garments to get distress look. Location can be front thigh & back seat or it can be overall / global application as per standard. Emery paper (silicon) is being used to scrap the garments in particular placement. Emery paper comes in different number generally starts from 40 till 600 and above, higher the number finer the emery paper, lower the coarseness of the paper.

In garment industry from 220, 320 & 400 number papers are most popular & widely used. Purpose of doing this process is make used worn out look to the garments. The most important factor is to select right number of paper according to the fabric strength & intensity need. Feathering /merging white sanded part to dark blue area in such way that it should look natural & not artificial.

Scraping can be done on inflated rubber balloons for better effect (horizontal or vertical it’s up to operator’s convenience), even it can be done on plain wooden board of garment size & hand pressure should be uniform in order to get better results.

Hand Scraping

PP spray (KMnO4) : Potassium permanganate spray is done on denim to take a

bright effect on sand blast area. One important thing about the potassium permanganate spray is, this is usually a sporting process to increase the effect of sand blast.

Potassium permanganate solution is sprayed on the blasted area of denim garment with the help of a normal spray gun. This potassium permanganate spray appears pink on the 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 the next process. It is always followed by neutralization process.

Sodium Meta bi-sulphate is most commonly used neutralizer. A number of products are available in the market for the neutralization process like sodium meta bi-sulphate selected on the bases of effect required on blasted area.

PP Spray

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

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

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

PP Spray

PP Spray

WHISKERWhiskers are one of the most important designs of a used look garment. The idea of whiskers is taken from the worn out lines and impression patterns generated by natural wearing on hips and front thigh area. On old denim, a number of patterns can be find consequential to fabric, body shape of user or sitting posture.Methods: Various methods are designed to create this impression on

denim. 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. 

WHISKER Sometimes separate patterns are made and fixed on balloons

to make mustaches. These patterns are made of thin rubber sheets and electric wires or rubber cords and pasted on balloons for pattern lines. Thin line patterns are very easy to work in that way but it is not much successful for broad lines.

Engraved patterns on thick board like hard rubber sheets are widely used for whiskers impression making. This idea is very simple to draw lines on rubber sheets and engrave them with blade. Garment is places on sheet and scrapped on specific area to draw this impression on garment. For its low cost patterns, it is most frequently used in small industries especially where the production is not consistent to style.

In some workshops it is done manually with the help of sharp edge rolled on fine wood sticks of pasted on plastic material. Before starting execution, placement and pattern must be marked on garment, this will help operator to execute the pattern right to match the aesthetics of garment.

WHISKER

WHISKER

Destroy:

One of the most popular distressing effects currently, ‘Destruction’ is an art which make denim look unique & used.

To make destruction pen type of stone tools being used in mid of wash process to apply on desired area. It can also be achieved by cutting it thru knife the warp yarns & keep the weft yarn as is to show white thread.

Holes also can be made by cutting weft & warp yarns. These are all manual processes & every garment will look unique & different than others.

Destroy

Destroy

Grinding

Grinding is being done on pocket edges & bottom hems edges by running against abrasion surface or stone to achieve worn out effect.

Many different make of machines & pen grinding tools are available in the market which runs with pneumatic system.

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 a 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.

Grinding

Grinding

CHEVRON

On denim, 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 roller 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. A chevron effect on Denim .

This operation is carried out in width direction hence it appears intense than hand sand with less strokes, because hand sand is carried out in length direction.

CHEVRON

TACKING

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.

TACKING

Garment is folded on specified areas and the fold is locked by tag pins. Now the garment is processed in washer and a permanent fold appears after removal of tag pin. This is important that tag pin is removed when the garment is dried completely.

The inner of the fold is dark in shade due to less exposure to mechanical rubbing and chemicals. Variation is provided by using different lengths of tag pins varying from 05 mm to 15 mm. This range of length is more commonly used in industry.

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.

TACKING

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 affect appears is very similar to the worn out denim.

Sandblasting has become the key method for finishing most modern denim requiring that ‘worn-out’ look. Under the sandblasting process the denim is smoothed, shaped and cleaned by forcing abrasive particles across it at high speeds. The process is fast and cheap and demand for pre-worn denim has led to a massive rise in its use. But this fashion comes at a price: the health and even the lives of sandblasting workers.

A single worker can produce between 20 and 30 pieces per hour hand-sanding while with manual sandblasting he could make between 35 and 60 pieces.

SAND BLASTING

Sand blast provides a very uniform result which cannot be achieved with its alternates. Its specialty is the merging effect that is blended with such a beauty that it has no difference with natural effect. Sand Blasting Effects on Denim High pressure of air produces a powerful backward thrust to operator so it is always recommended to fix the gun in appropriate stands rather than placing it on shoulders or using it with bare hands.

On some fabrics sand blasting is not successful for it covers the characteristics of fabric. Especially in fabrics which are famous for Slub patterns it flattens the look. 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.

SAND BLASTING

Resin Application (3D Effect)

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.

3D Effect

3D Effect

LASER TECHNOLOGY

It is a computer controlled process for denim fading. This technique enables patterns to be created such as lines and/or dots, images, text or even pictures. It is water free fading of denim. Being an automatic system, chances of human error are slim. Also called spray painting in denims. This technique has relatively high cost

Replacing Traditional Technique for Denim Finishes The laser technology is the fastest growing technique presented by many

companies as a perfect replacement for traditional methods of sandblasting, stone washing, burning, etc. and much more that the industry has yet not seen. The success of the technology is based on the fact that Indigo today is a synthetically produced vat dye that is bound to the fabric by mechanical forces rather than chemical and unlike other vat dyes, Indigo has very little affinity to cotton making it suitable for washed down treatments.

The various laser techniques available in the industry are considered a much safer, environment friendly, economical and superior technology that has advantages that offers not only aesthetic variation but also gives freedom to designers to innovate at quick speed saving critical commercial time in product development and crucial cost during production. According to experts the technologies on offer increase output per workstation by almost 500 % while reducing loss of fabric strength by 50%.

LASER TECHNOLOGY

Another advantage that is interesting for users is the significant elimination of environmental problems associated by previous abrasive processes while having the ability to replicate an exact abrasion pattern on all units besides infinite flexibility to create different ‘worn look’ designs otherwise impossible. The health benefits cannot be undermined as processes like hand sanding generate tremendous amount of dust that can be detrimental to workers health.

Wastages in processes like stone washing where considerable wear and tear on machine and excessive water is normal are also significantly reduced, as there is no wear and tear and zero water application. In fact the industrial design and in built cooling system allows the machine to run continuously for hours and requires minimal maintenance. 

Not only can denim be laser engraved, but pile fabrics as well. The laser burns away the pile in selected areas leaving a permanent design that closely mimics and embossed pattern. 100% cotton corduroy and velvet can be laser engraved to produce an impressive permanent design without the use of resins

LASER TECHNOLOGY

LASER TECHNOLOGY

JEANOLOGIA

The textile laser and the eco-washing machine G2 was shown at ITMA Barcelona. This new technology makes possible savings of 62% of power, 67% of water and 85% of chemical products and 55% of time in denim finishing Jeanologia company presented latest innovations for Denim finishing, under the slogan of 3E (Ecology, Efficiency and Ethics), that allows to get greater energy, water, chemical sand time savings. Jeanologia has long been a pioneer in the development of textile laser which has avoided the use of unhealthy techniques and has reduced the energy consumption and the pollution

The new laser technology will allow greater production compared with other ways of jean finishing such as manual scraping, spray or sandblasting. Laser offers high levels of productions.

New technology for denim finishing, faster and with less energetic consumption

JEANOLOGIA

As well as laser, Jeanologia has G2Technology, an eco-washing machine that works only with active oxygen and ozone, allowing wash denim and shirts with vintage finishing, without using water or chemicals.

With laser technology 100 or 200 of denim can be produced per hour, while manual scraping produces only 10 units per hour, sandblasting 30 and spray 60. Specifically, the G2 technology allows to save per garment a 62% of Kw/h, a 67% of water (liters), an 85% of chemical, as well as a 55% of production time.

Conclusion

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.

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.

Thank You