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)



COLORANT LTD                                                                                                              Plot No. 116, Phase II                                                                                              Near Ambica Cross Road                                                                                          G.I.D.C.Vatva,

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.