EXTRACTION OF DYE FROM HIBISCUS FLOWER AND APPLICATION OF IT ON WOOL

EXTRACTION OF DYE FROM HIBISCUS FLOWER AND APPLICATION OF IT ON WOOL

Textile is one of the profit making and rising industries in India. It not only creates a huge amount of employment but also generates a substantial amount of revenues by virtue of import. Textile industry consumes a very high amount of dyes, chemical and auxiliaries, some of which are hazardous in nature.It also creates a substantial amount of pollution.One of the fascinating aspect of environmental issues is that an environmental chemical, auxiliaries and dyes till yesterday were considered safe may carry the tag of generally recognized as safe today and tomorrow, they may be dubbed as hazardous one

-Natural dyes have pharmacological effects and possible health benefits.
-They are obtained from renewable sources.
-Natural dyes cause no disposal probes.
-They are biodegradable. Hibiscus flowers and leaves are available easily in India.
-A very little and scattered information about modification and standardization of natural dyeing process is available. Thus we have attempt to explore the possibility of process modification and standardization of dyeing of wool and wool and human hair textiles with natural dye. By using ecofriendly natural dyes.  Therefore it was thought that by making use of Hibiscus flowers and leaves and extraction color from it and further use this dye for the coloration of Wool and human hair and wool fabric. And further make use of remaining trash of flowers and leaves as compost.

PROCEDURE FOR EXTRACTION OF COLOUR OF HIBISCUS:

• Aqueous method : Boil the dyestuff in soft water at 100 degree celsius. Filter the dye solution and record the optical density.

• Alkaline : Prepare 1% alkaline solution with addition of sodium carbonate or sodium hydroxide in water. Enter the dye material in it and boil the same at 100 degree celsius. Filter the dye solution and record the optical density.

• Acidic  method : Prepare 1% of acidic solution by adding HCL in soft water. Enter the dye material and boil it at 100 degree celsius. Filter the dye solution and record the optical density. 

• Alcoholic method :Alcoholic solution is made by adding equal amount of alcohol and water. Enter the dye material and boil it at 100 degree celsius. Filter the dye   

      

DYE EXTRACTION:

     Petals that are all the same color when they are in  full bloom, or gather leaves from the plant Dry the petal at room temperature for 3-4 days. Put the petals into a pot boil the mixture for 2 Hr place  a strainer over another pot and pour the dye mixture through the strain

APPLICATION OF NATURAL DYES ON TEXTILES:

• Dyeing process for natural colouration of wool :

1. Wool and silk are natural protein fibers and are available in wide variety having varied qualities. Both the fibers has complex chemical structure and very much susceptible to alkali attack (at pH >9).
2. Hence, dyeing of these fibres with natural colours needs special care avoid fibre damage by alkaline pH. Moreover, both wool and silk contain both amino and carboxylic functional groups. While, wool contains equal number of amino and carboxylic groups held together as salt linkages which bridge the main peptide chains. 
3. Therefore, in aqueous solution, wool carries no net charge. However, silk fibre has a slightly cationic character with the isoelectric point at about pH 5.0. Also, silk is less sensitive to temperature. Therefore, selection of mordants, conditions of mordant, pH and other conditions for dyeing, necessary cares are to be taken for colouration of these textile fibres for mordant and application of natural dyes. 
4. Wool and silk fibre based textiles can be dyed with different natural colours mostly through pre-mordanting or post mordanting system. Mordanting is done with tannin rich natural source chemicals like harda, gall nut etc and/or metal salts like, alum, aluminium sulphate, ferrous sulphate etc. 
5. Depending on shade depth requirement, mordant and dlye concentration are to be determined.
6. Dyeing conditions for a particular fibre-mordant–dye system need to be optimized by study of dyeing process variables before bulk dyeing. In pre-mordanting system, these animal fibre based textiles are selectively mordanted (single or sequential double mordanted) with 5-20% (owm) mordant at 80-90°C for about 30-40 minutes having ML ratio 1:5-1:20 and can be taken for subsequent dyeing generally without washing. 
7. The pre-mordanted samples are entered in the dye bath (generally acidic dye bath) at 50-60°C and ML ratio 1:20, raise temperature upto the optimum dyeing temperature (may be 90°C) and dyeing is then continued for further 30 to 40 minutes followed by thorough rinsing, soaping and washing. 
8. However, in post mordanting system of applying natural colour on wool and silk textiles, dyeing is done at optimum dyeing condition and the dyed samples are dip into a mordant bath containing mainly 1-2% metal salt (owm) for true colour development 

• PUBLISHED BY:

KOMAL MADDEWAR.

DEPT. OF TEXTILE TECHNOLOGY.

DKTE TEXTILE AND ENGINEERING INSTITUTE.