Student Activity Packet

Activity 3: Dyeing with the Natural Dye Tumeric

Description

This hands-on experiment gives you first-hand experience with the skills, materials, and equipment involved in the dyeing process. It is an example of a use of the scientific method with its concerns for consistent processes and careful observation. Begin by reading the Student Essay "Where Do Colors Come From?"

Dyeing with the Natural Dye Turmeric - Experiment Instructions

In this experiment, you will use a natural dye bought at the grocery store.

FOR YOUR SAFETY -- Remember:

  • You are making a dye and it could stain your clothes, so wear an apron.
  • Since you will be heating the dyes, protect your eyes by wearing goggles.
  • Always add dry chemicals to water. Never add water to chemicals.

    Materials:

    - goggles
    - oven mitts
    - measuring cup
    - enamel or stainless steel pan
    - clothes line
    - stop watch
    - 1/4 teaspoon of turmeric (available at the grocery store spice counter)
    - 2 cups of water
    - thermometer (such as used to make candy)
    - 4 pieces of one-foot-long white wool yarn
    - 4 squares (4 inches x 4 inches) of 100% cotton cloth; (such as an old sheet)
    - stirring rod or spoon
    - a heat source such as a hot plate or stove top.
    - a sink or bowl of hot water and a bowl of cold water
    - paper towels

    Procedure:

    1. Mix the water with the turmeric in an enamel or stainless steel pan.

    2. Heat the water to a little above body temperature (38-48 degrees Celsius or 100-120 degrees Fahrenheit). Stir while heating.

    3. Add the yarn and the cotton. Continue to stir.

    4. Slowly bring the water and turmeric mixture to a simmer (a simmer is below a boil -- the surface of the water should bubble quietly) and simmer gently for two or three minutes, stirring lightly to move the yarn and cotton around.

    5. Carefully lift the wool or cotton out of the simmering water and turmeric. Rinse the wool in hot water and squeeze gently. Rinse in cool water and again squeeze gently.

    6. Hang in a shady place to dry.

    Dyeing with the Natural Dye Turmeric - Questions

    Pre-experiment Questions:

    1. Describe the turmeric, by appearance and odor, before you put it into the water.

    2. Look at the turmeric plant.

      Turmeric
      Carol Ann Rinzler, The Complete Book of Herbs, Spices
      and Condiments.       (New York: Facts On File, 1990). Used by permission.

      How do you think that the turmeric plant was ground into the powder you are using in your experiment? Which parts of the plants were used? How long do you think this grinding process took?

    Post-experiment Questions:

    1. After the cotton and the yarn have dried, compare the colors of each of the fabrics. Describe the color of the yarn and of the cotton.

    2. Are the colors the same? If they are different, why do you think they are different?

    3. What would you have to do to dye the yarn and the cotton the same color yellow?

    4. Compare your groups' dyed yarn and cotton with that of another group. Are the dyed pieces of fabric the same color? Explain why you think they are similar or different.
    Color Intensity Over Time

    Dyeing Time Dyed Color In Sunlight In Dark
    ------ yarn cotton yarn cotton yarn cotton
    2 min. ? ? ? ? ? ?
    4 min. ? ? ? ? ? ?
    6 min. ? ? ? ? ? ?

    Place one dyed cotton square and yarn strand from each timed dyeing trial in the bright sunlight. Place another dyed cotton yarn strand in a dark location. After several days attach a dried sample of each material to the chart and compare the results.

    1. How do the two fabrics compare in color intensity when placed in the sunlight? Is there any change in color intensity based on how long the fabrics were exposed to the dye?

    2. If there was a change, why do you think the sunlight caused a change in color?

    3. Was there any change of color intensity in the fabric that was placed in the dark location?

    Test your dyed cloth for color fastness.

    Wash one dyed cotton square and one strand of dyed yarn in soap and water. Attach a sample of each to the chart page. Compare the color intensity of the washed and the unwashed samples. What do you think is contributing to the final color intensity?

    Copyright © 1998 The Lemelson Center for the Study of Invention and Innovation, National Museum of American History, Smithsonian Institution. All rights reserved.

    Comments and questions to the Lemelson Center:lemcen@si.edu

    Last Revision: 6/5/98