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Page 98 - Shawl Weaving Artisan - TP
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    Textile & Handloom                                                               Exercise 1.6.59
           Shawl Weaving Artisan - Wet Processing

           Extraction of natural dyes

           Objectives : At the end of this exercise you shall be able to
           •  analyse the extracted natural dyes from different sources.

             Requirements
             Materials

             •  Note book                       - 1 No.         •  Sharpener                         - 1 No.
             •  Pencil                          - 1 No.         •  Eraser                            - 1 No.

           PROCEDURE

           TASK 1: Extraction of natural dyes

           Step 1: Harvesting and collection                    •  Use a cheesecloth, filter paper, or a centrifuge to
           •  Collect plant  materials such as leaves, flowers,    separate the liquid from the solids.
              roots, or bark.                                   Step 5: Concentration

           •  Ensure the materials are fresh, healthy, and free of   •  Concentrate the extracted liquid through evaporation,
              contaminants.                                        distillation, or freeze-drying.
           Step 2: Cleaning and preparation                     •  This step helps to increase the color intensity and
           •  Clean the plant materials to remove dirt, debris, or   stability of the dye.
              impurities.                                       Step 6: Standardization
           •  Chop, crush, or grind the materials to release their   •  Standardize the extracted dye to ensure consistency
              colorant compounds.                                  in color and quality.
           Step 3: Extraction                                   •  This step may involve adjusting the pH, temperature,
           •  Use a solvent, such as water, ethanol, or glycerine,   or concentration of the dye.
              to extract the colorant compounds  from the plant   Step 7: Storage
              materials.                                        •  Store the extracted dye in  a cool, dark place to
           •  Heat, stir, or steep the mixture to facilitate extraction.  preserve its color and stability.
           Step 4: Filtration                                   •  Use  airtight  containers or  glass jars to  protect  the

           •  Filter the extracted liquid  to remove solids and    dye from light, oxygen, and moisture.
              impurities.

           TASK 2:  Ask trainees to extract the dye from natural materials like fruits, vegetables, leaves, flowers, stems
                   etc. and write all the observations in the below mentioned (Table 1)
                       Natural dye        Extraction
            S.No.                                             Solvent          Temperature            PH
                         source            method

              1

              2

              3

              4

              5

           86

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