Coloring fabrics with dyes from plant materials

Developers:

Nancy Werner

West Rockhill Elementary, Perkasie, PA

Donna S. Grecian

Analytical Research, Rohm and Haas Company

Grade Level:

4 through 6

Discipline:

General Science

Goals:

Understanding basic color theory and color separation/chromatography.
Preparing colored dyes from plant materials.
Compare and contrast various fabrics in these dyes.
Investigating effects of acid and base on color.

Activity 1: Color Theory (Teacher Demonstration)

Objectives:

Upon completion of this exercise, students will be able to:

1. Predict the color outcomes that result from combinations of colors.
2. Demonstrate that combinations of 2 of the 3 primary colors will create 3 secondary colors.
3. Record observations of the color mixtures.

Background:

Color surrounds us everywhere. We see it in the sky, in the oceans, and in all plants and animals. Color adds beauty to our clothing and food. But to discover color, we need to examine it. We used liquid chromatography to discover the basic color theory.

However, we wanted to continue our experimentation with color through the world of plants. Until the 1850's, all dyes were of a natural source so we went to our garden beds and selected various fruits and vegetables to test. We also selected a variety of fabrics that we could test in the dye baths. We wanted to discover the fabric's variability in holding the colors of the plant dyes. We must note that our dye baths were all water based. We refrained from adding any mordants to the dyes. We also created acid (vinegar) baths and alkaline (baking soda) baths to see whether these addends produced any effects to our fabrics. We were thrilled with our findings as brilliant colors were exposed to us.

Our last series of experiments was liquid chromatography to see whether the plant baths - plain, acid, or alkaline would show separation. Again we were delighted with our findings that plant dyes are all different as they travel the chromatography column.

Materials:

Food coloring dyes (McCormick liquid kit)
Dropper bottles
3 clear containers filled halfway with H₂O
Rubber gloves
Art smocks

Teacher Preparations:

Using food coloring, combine 5 drops of dye with 10ml H2O in small jar or dropper bottle. Make a dropper bottle for the red, yellow, and blue. Note: Yellow will look orange because of concentration.

Procedure:

1. Using the 3 primary dyes from the color kit-red, yellow, and blue-prepare the secondary colors in 3 other dropper bottles.
   

   	Ratios:	10 drops red + 5 drops yellow = orange
   		5 drops blue + 5 drops yellow = green
   		5 drops blue + 10 drops red = purple

   Hints:
   

   •	Add yellow to the water first so students can see it actually is yellow-in the color kit it is so concentrated it looks orange.
   •	Check your dye stock solutions prior to the demo for color fading.

2. In 3 clear cylinder containers filled halfway with H2O, drop the primary colors to create the secondary colors. Predict results prior to adding second color to the container. Observe results. Record observations on worksheet.

Observations/Discussions:

1. Students will observe the combining of pairs of the 3 primary colors that will provide the 3 secondary colors.
   

   	Red + blue = purple
   	Yellow + blue = green
   	Red + yellow = orange

2. Discuss the process of dye combinations.
3. Discuss the concentration effects.
4. Predict what would happen if you added more drops to the colors.

Extensions:

1. Provide droppers with different colors not present in the lesson-e.g., brown, black, or gray.
2. Develop a color wheel using color pencils.
3. Predict outcome of combining various colors in the color wheel. Test hypotheses.

Worksheets:

Worksheets for Activity 1 are available for download in PDF format:

•

color1.pdf  (6K)

Activity 2 - Extraction of Dyes

Objectives:

1. Identify the plants and discuss each of them with the students.
2. Predict the colors that each plant will provide.
3. Compile table to record the experimental conditions-plant type, weights of plant material and H2O, and temperature.

Materials:

Heating sources - enough to make the required number of batches
5 heat resistant containers or beakers
H₂O
Rubber gloves
Tongue depressors or spoons for stirring
Assorted plant materials—we used fresh spinach, red beets, red

raspberries, carrots, and onion skins. Frozen or canned products can be used if fresh produce is not available, although we have observed color differences likely due to the salt in the canned goods (our development of this experiment was based on fresh produce).

Cooking thermometer
Art smocks
Strainer

Safety Notes:

1. The preparation of vegetables should be done by the teacher or with parental guidance.
2. The hot plates and beakers should be placed in a safe area of the classroom.
3. A caution strip would be beneficial to denote this cooking space.

Procedures:

1. Record all weights in chart on worksheet.
2. Cut all plant items as small as possible.
3. Weigh glass beaker. Add plant matter and weigh again.
4. Add 400 ml H2O to each container of plant matter.
5. Place on hot plates or heat source in a safe area away from students.
6. Allow to simmer for 4 hours. Stir occasionally. Teacher will measure final temperature of each bath and provide information to students.
7. Remove from heat and allow plant materials to soak overnight.
8. Strain next morning into clean jars or containers.
9. Discard cooked plants.
10. Refrigerate if keeping longer that 24 hours, as material begins to ferment.

Observations/Discussions:

1. Student will predict outcome of cooking plants.
2. Student will list which plant that they like best of the 5 choices.
3. Student will discuss the texture, absorbency, H2O content, size of the plant cuttings, and what part of the plant is being cooked - leaves, stems, roots, etc.
4. Student will discuss why carrots do not result in orange dye (due to water insolubility of beta carotene).
5. Student will discuss the size of the cuttings and whether this makes a difference in the cooking.

Extensions:

1. What other plants could we use-flowers?
2. Invite students to bring other plants or flowers to class.
3. Predict what else might happen with the various plants-e.g., unexpected colors, solubility effects, temperature effects.
4. Do experimentation with these various plants.

Lab Notebook

Use the form provided in Activity 1.

Worksheets:

Worksheets for Activity 2 are available for download in PDF format:

•

color2.pdf  (11K)

Activity 3 - Dyeing the Fabrics

Objectives:

1. Investigate the effect of the dye bath on a variety of natural and synthetic fabrics.
2. Compare and contrast the final fabric colors based on the fabrics and solutions.

Materials:

Teacher Preparation: Prewash, and precut each fabric into 2" X 6" swatches.

Widemouth jars/beakers of strained juice from plants (1 dye bath per group)
Aluminum pans
Paper towels
Tongue depressors
Rubber gloves
Fabric scissors
Art smocks
Acid bath-30ml of vinegar in 300ml of H2O (one per group)
Base bath-one tablespoon of baking soda in 300ml of H2O; stir until dissolved (one per group)

Procedure:

1. Wet the fabric swatches, and squeeze out the excess.
2. Completely submerge the swatches into the dye baths and let sit for 15 minutes. Carrot/Spinach teacher demo can be done during this 15 minutes wait-since both produce little to no color, it is not necessary to soak the demo fabrics for 15 minutes.
3. While wearing rubber gloves, take one swatch from the bath, and let the excess dye drip off.
4. Cut each swatch into 3 squares. Place one square to dry on a paper towel. The second and third squares should be placed into the acid and base baths, respectively.
5. Stir the acid/base baths. Remove the squares and let excess liquid drip off (wear gloves).
6. Place the 2 squares on 2 separate towels to dry. Label the towels "control", "acid", or "base" to prevent confusion. Record your observations.
7. Repeat steps 3 through 6 with the remaining fabric swatches.

Observations/Discussions:

1. Students will discuss the various results.
2. Which fabric showed lots of change?
3. Which fabrics showed little change?
4. Which fabrics changed when placed in the acid bath? How did they change?
5. Which fabrics changed when placed in the base bath? How did they change?
6. Were you surprised with any of the findings? Red raspberry dye in base bath becomes a dark, steel blue-gray and onion skin dye in base becomes a bright yellow.
7. Explain the negative reaction of the carrots with no color on the fabrics.
8. Observe and record fabric results.
9. Rank the fabrics from lightest to darkest.

Extensions:

1. Predict the outcome of 3 different plants-vegetables or flowers.
2. Prepare dyes to test the predictions.

Lab Notebook

Worksheets:

Worksheets for Activity 3 are available for download in PDF format:

•

color3.pdf  (5K)

Activity 4 - Color Separation by Paper Chromatography

Objectives:

1. Determine that secondary colors are combinations of primary colors.
2. Recognize that plant dyes of the same color are not necessarily the same compound.

Materials:

Chromatography paper cut into 4" x 6" pieces (teacher prep)
Widemouth clear containers for developing chambers (2 per group)
Water
Microdroppers
Pencil/ruler
Stapler
Dye bath from processed plants
Vinegar
Baking soda
Dropper bottles from color kit (See Activity 1)
1-oz glass vials (3 per group)

Procedures:

Part 1: Food Coloring Chromatography

1. Use the color kit from Activity 1 for this experiment.
2. On a 4" x 6" piece of chromatography paper, draw a line 1/2" away from and parallel to the long edge of the paper (this is the bottom).
3. Place a drop of each of the 6 colors from the kit on this one line, spacing drops about 3/4" apart.
4. Roll the paper into a tube and staple together with 3 staples. Do not overlap the edges.
5. Pour about 1/4" H2O in a widemouth clear container.
6. Place the paper tube, with the spots at the bottom, in the clear container. The bottom edge of the paper will sit in the water. Do not let the paper touch the sides.
7. Record your observations.

Part 2: Plant Dye Chromatography

1. Using the dye bath assigned to your group, pipet 1 dropperful of the dye into each of three 1-ounce vials.
2. Add 1 dropperful of vinegar to one vial; label this vial "Dye + acid".
3. Add 1 dropperful of baking soda solution to the second vial; label this vial "Dye + base".
4. Label the third vial "Dye control".
5. Prepare a second 4" x 6" sheet of chromatography paper according to the directions in Step 2, Part 1 above.
6. Place a drop of each of the 3 vials the line, spacing drops about 1" apart. Label the spots A (for acid), B (for base), and C (for control). Hint: you may need several drops-let each drop dry before adding the next drop to minimize spreading.
7. Roll the paper into a tube and staple together with 3 staples. Do not overlap the edges.
8. Pour about �" H₂O in a second widemouth clear container.
9. Place the paper tube, with the spots at the bottom, in the clear container. The bottom edge of the paper will sit in the water. Do not let the paper touch the sides.
10. Record your observations.

Observations/Discussions:

1. Students will observe the capillary action of the chromatography paper and watch the colors. A paper towel absorbing water is a good analogy for capillary action.
2. Students will observe the patterns and levels of each plant's dye.
3. Students will compare/contrast the pattern seen with the plant dye bath with those seen with the acid and base baths.
4. Observations to note for the chromatography:

   	Onion:	control drop does not move up the paper
   	Onion:	acid drop does not move up the paper
   	Onion:	base drop moves up the paper with the water and is deep yellow
   	Raspberry:	control drop moves up the paper with the water and is deep pink
   	Raspberry:	acid drop moves up the paper with the water and is deep pink
   	Raspberry:	base drop moves up the paper, splitting into yellow and purple spots
   	Red beets:	control drop moves up the paper with the water and is reddish purple
   	Red beets:	acid drop moves up the paper with the water and is pale pink
   	Red beets:	base drop moves up the paper with the water and is deep pink/purple with an orange center and a yellow tail

   Note: Color intensities will vary based on number of drops used and concentration of dye bath.

Extensions:

Try repeating the experiment using different plant materials based on student suggestions. Have students predict results and test their hypotheses.

Lab Notebook

Use the form provided in Activity 1.

Worksheets:

Worksheets for Activity 4 are available for download in PDF format:

•

color4.pdf  (5K)

References:

1. Buchanan, Rita. A Dyer's Garden. CO: Interweave Press, Inc., 1995.
2. Kowalchik, Claire and William H. Hylton, editors. Rodale's Illustrated Encyclopedia of Herbs. Emmaus: Rodale Press, 1987.
3. Smith, Alastair. The Usborne Big Book of Experiments. New York: Scholastic. 1996.
4. Tunis, Edward. Colonial Craftsmen and the Beginnings of American Industry. New York: Thomas Y. Crowell Co., 1965.