Dr N.N.Mahapatra
B.Sc( Hons),B.Sc (Tech )(Bom)M.Sc ( Chem ),Ph.D ( Chem ),M.B.A( IMM,Cal)
C.Col FSDC ( UK),CText FTI ( Manchester ),Int Trg ( Australia)),Sen Mem ,AATCC (USA),FAIC(USA)
FIC ,FTA , FICS,FIE,FIIChE ,MISTE ( INDIA)
President
COLORANT LTD Plot No. 116, Phase II Near Ambica Cross Road G.I.D.C.Vatva,
Ahmedabad-382445
Gujarat,India
Technology breakthrough always is the source of inspirations and advantages . It replaces the older generation of technology and induces linear,step by step strategy of technology substitution.The technology fusion approach is non-linear , complimentary and co-operative ; blends incremental technical improvements from several previously separate fields of technology to create new and innovative products . Owing to the continuous development of new fields of application as well the claim of an increased economy ,special products and corresponding techniques are getting momentum. Technology breakthrough creates and produces new and innovative products by different diversifications in the existing spinning technology .The desirable physical and /or technical properties of the existing melt spun fibres as well as solution spun fibres can be achieved by appropriate control and /or modification in the spinning and post spinning operations and /or modifications in the polymeric materials used for spinning .On this assumption , by making the melt spinning as well as solution spinning system more versatile , different types of fibres can be produced.
Fibre Innovation Technology , Inc. ( F.I.T), has become the first North American fibres manufacturer to offer Ingeo , a breakthrough material that allows man-made fibres to be derived from 100% annually renewable resources. They have signed an agreement with Cargill Dow LLC to produce and sell Ingeo fibres in North America and selected Asian markets. In January 2003 ,Cargill Dow LLC introduced Ingeo fibre to the textile world .
Ingeo , the fibres start life as a plant such as corn . Plant sugars are fermented and turned into a high performance polymer known as polylactide . Ingeo is the brand name given to the man made fibre , produced from polylactic acid ( PLA ). It is made annually renewable natural sources such as corn , and being fully compostable .PLA has been of interest for many years in a limited way , mainly in medical applications . But now Cargill Dow has established the technology and is being used for various textile end uses.
Combined with the increasing consumer understanding of the importance of the various environmental advantages – renewable resources , minimizing the use of fossil fuels , compostability , reduced greenhouse gas emissions – the scope for such a fibre is most exciting , both commercially and technically . Ingeo fibres has permeated the conscience of the apparel world across the globe and through the supply chain embodying a new approach towards environmental responsibility as a lifestyle philosophy for the future . Ingeo fibres represent a new brand concept based on the principles of sustainability – economic viability , social responsibility and environmental soundness . Ingeo claims to represent the worlds first man-made derived from 100% annually renewable resources. Imagine a polymer used to make everything from packaging and consumer goods to fibres for apparel and furnishings , derived from renewable resources instead of oil . Polymer that offers more disposable options and is more environmentally friendly to manufacture than traditional petroleum based plastics . Derived from 100% annually renewable resources such as corn ,the product , NatureWorks polymer ,is the world ‘s first polymer showing a significant reduction in greenhouse gas emissions .
Manufacturing – The process to make Ingeo fibres is based on the fermentation of simple plant sugars to create a proprietary polymer which is spun into a fibre . In other words the man-made fibre is created by converting corn into a polymer which is spun into a fibre . The polymer is known as polylactide or Natureworks PLA . The ingeo fibre is extruded from Natureworks PLA and then manufactured into filaments, staple fibre etc.
Yarns,fabrics and garments made from Ingeo fibres can be processed on conventional machinery through all of the manufacturing stages ; there is no need for any capital investment in plant . In many of the downstream processing sectors –fibre spinning ,yarn spinning , fabric production and dyeing and finishing – Ingeo fibre is comparable with polyester . Both are available in filament and staple form ; they are melt spun ; weaving and knitting set-up conditions are similar ; fabrics can be heat treated to give dimensional stability .and they are both dyed with disperse dyes .
Properties of Ingeo fibres – Ingeo fibre combines the qualities of natural and synthetic fibres in a new way . Strength and resilience are balanced with comfort , softness and drape in textiles .Amazingly ,and in addition , Ingeo fibre is naturally flame retardant and has good moisture management characterstics .It has got good stain resistance properties . Ingeo fibre balances strength and resilience with comfort , softness and drape in textiles . Ingeo also uses no chemical additives or surface treatments and amazingly ,is naturally flame retardant . Ingeo fibre stain resistance properties make it an ideal carpet fibre for the home ,the office and transportation . However it is important to recognize that both fibres are unique and do behave differently .This recognition is now confirmed by the fact that PLA ( also called Ingeo) is acknowledged in both the USA and Europe as a generic fibre in its own right.
The melting point of PLA is 170 deg c . The heatseting is done at 125-130 deg c for 30 secs. Hydrolysis degradation of the polymer will occur ,particularly under combined aqueous high-temperature and alkaline conditions . The degree of hydrolysis is influenced by time ,temperature and pH ,and can be safely controlled by modification of the dyeing and finishing processes .
Dyeing and Finishing of Ingeo fibres – As always with any new fibre ,the pretreatment ,dyeing and finishing processes need special attention ,mainly in meeting the needs of the fast-moving ,fashion –driven , performance –demanding apparel sector. PLA fibre is dyed at 110-115 deg c as compared to PET fibre which is dyed at 130-135 deg c . It is found that the individual dye shades are hypsochromic and brighter than on polyester fibre , and show a greater variation in exhaustion levels . For accurate and successful dyeing ,the dyeing behaviour on a Ingeo substrate must be understood.. During the last two years ,major dye companies like Dystar and Clariant have identified a range of selected disperse dyes ,showing good exhaustion and leveling /migration properties on Ingeo fibres ( like Disperse Yellow 54 , Disperse red 60 ,Disperse blue 56 etc) .Dystar has recently published an Ingeo Fibre Coloration Pack which gives comprehensive details about selected dyes and the processing parameters for Ingeo fibre and blends. ( like Dianix Crimson SF , Dianix Luminous Red G , Dianix Yellow Brown CC , Dianix Rubine CC and Dianix Blue K- FBL ).
Ingeo fibre is generally sufficiently clean to only require a mild scour ; still then to ensure the complete removal of spinning oils ,fabric processing lubricants ,etc . If a bleach treatment is to be used for dyeing bright pale shades ,then a mild process as below is adequate
Soda ash – 3 gpl Hydrogen Peroxide( 35 % ) – 3 ml/lit.Stabilizer -0.5 gpl. Wetting agent – 1 gpl Run at 95 deg c for 30 mins Hot wash- cold wash –neutralize.
If a fabric is to be bleached than add Optical Whitener at 110 deg c . Like disperse dyes only selected Optical Whitener ‘s are used.
The normal dyeing temperature is 110 deg c for 30 mins , but in dark shades the temperature is raised to 115 deg c to increase the colour depth and better exhaustion. But care should be taken not to give more hold time at high temperature which may lead to loss of fibre strength . Levelness of shade is not a problem in Ingeo fibre dyeing. Still then the dye selection and process parameters setting should be careful.
For light and medium shades slight soaping is required after dyeing process but in case of dark and heavy dark shades reduction cleaning is required. It may be as follows
a. alkali reduction clearing .
b. acid reduction clearing .
Both the above processes has to be followed in such a way to avoid hydrolysis degradation.The process for alkali reduction clearing is Soda ash – 2 gpl. Sodium hydrosulphite( hydros) – 2 gpl. Run at 60 deg c for 15 mins.
This leads to no significant change in shade and better wash fastness . But in acidic reduction clearing ( use Cyloconon ECO ( BASF ) – 1-2 gpl at pH 4-5 ) will give less fibre hydrolysis and is considered more environmentally positive.
Wash and light fastness results tend to be slightly lower , compared to the same shade on standard polyester.
Blending with Ingeo fibre — The most common blend is with cotton like Cotton/Ingeo 70/30 .Besides Ingeo fibre is also blended with wool and silk in various proportions. There is real potential of Wool/Ingeo fabric blends because not only of the positive environmental benefits , but also due to their compatible physical stretch and recovery properties .As fabrics in 100% Ingeo fibre and Ingeo fibre blends continue to be developed by the mills ,then similarly the amount of technical knowledge on spinning ,dyeing and finishing is being expanded .
While dyeing Ingeo /Cotton blends care should be taken of the potential cumulative hydrolysis effect due to high temperature alkaline conditions while bleaching and dyeing of cotton portion. So in such cases the cotton portion is bleached using TAED ( tetra acetyl ethylene diamine )at a neutral or slightly acidic pH which leads to minimum hydrolysis degradation of the PLA fibre . Normally Bifunctional and Vinyl Sulphone reactive dyes are recommended for dyeing of cotton portion.
An alternative process for dyeing cotton portion is to use after-treated direct dyes .Such an application is done as a single stage all-in dyeing . Direct dyes have the following advantages in dyeing Ingeo/cotton blends
A.They are not applied from an alkaline medium and therefore do not cause degradation .
B. A shorter and more straight forward dye cycle.
C. Good all round colour fastness including dark shades ,by using a cationic after treatment such as Sirius B ( Dystar )
Uses of Ingeo fibres – Due to various inherent properties Ingeo fibre is ideally suited to fabrics from fashion to furnishings . Ingeo fibres is ideally suited for a range of textile products and applications where it competes with traditional fibres on a price and performance basis. It is also used for an ideal fibre for the home , the office and transportation . In nonwovens , Ingeo fibre can produce a whole unique new family of compostable products without compromising performance . Imagine a disposable diaper that is also completely biodegradable so that no waste is left to contaminate the earth .In fiberfill , for products such as pillows , duvets , comforters and padded outerwear , Ingeo fibres superior loft means that it feels more like down than a synthetic imitation. In industrial applications Ingeo fibres can be used for geotextiles , agrotextiles and special filtration media . Its consumer uses include carpets , garments , bedding and furnishings Global garment manufacturers around the world are using Ingeo fibres understanding that the fashion and apparel of today need to be conscientiously driven , allowing the consumer to enjoy nature while knowing they are also looking after it .
The other name for Ingeo fibres is PLA fibres ( polylactide fibre) which is being used successfully in apparel,furnishings,fubrefill,floorcoverings, industrial ( geo and agrotextiles) and nonwovens( diapers,hygine products , wipes)
The innovative and revolutionary Ingeo fibre represents a voice for this new trend that nurtures environmental responsibility and sustainability bringing it to the forefront of fashion’s conscience . The Ingeo /cotton blends 70/30 are used for Trousers ,Belted Fiberfill jacket and normal jacket. In addition to the menswear , the use also includes garments for women ,including Capri pants , gilet ,trousers and T-shirt .
In India textile companies like Raymonds, RSWM , Nahar and Vardhman have started using Ingeo fibres in various blends and selling it as value added item and getting a premium. Lastly Ingeo will soon establish itself as a mainstream fibre and truly the fibre for the 21 st century .
Acknowledgement – The author is thankful to Mr Subhash Bhargava FSDC ( UK) Technocrat and Founder ,Colorant Ltd for giving permission to publish this article.
