Document 91238

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P.O. BOX 219 • BATAVIA, ILLINOIS 60510 • 800/452-1261
Vol. 93-4
©1993 Flinn Scientific, Inc.
Tie-Dyeing ~Chemistry Fun
Penney Sconzo
Westminster School
Atlanta, Georgia
The art of dyeing probably originated in
India or China no later than 2500 BC. Most
natural dyes came from parts of plants such
as the bark, berries, flowers, leaves, and
roots. Because these dyes did not have a
strong attraction for the fibers being dyed, a
process known as mordantinq was used to
improve colorfastness. To react with acidic
dyes, fibers were treated with basic or
metallic mordants which might include
solutions of aluminum, copper, iron, or
chromium salts. Compounds formed by the
dye and the mordant, called lakes, prevented the colors from washing out and
made the color longer lasting. Such natural
dyes became less and less important as synthetic dyes that produced brighter colors
were developed. Today, Iogwood black is the
only natural dye widely used.
In 1856, William Henry Perkin began the
synthetic organic chemical industry by
accidentally discovering the purple dye,
mauveine, when he tried to produce quinine
from aniline. The synthetic dyes were known
as coal tar dyes because the six-membered
ring structures of carbon atoms were all derived from coal tar. Congo Red was the first
dye discovered with so great an affinity for
cellulose that a mordant was not required.
About 100 years after Perkin's first discovery, fiber-reactive dyes capable of forming
covalent linkages with the fiber were discovered. A fiber-reactive dye is washfast.
During dyeing, dye molecules must diffuse
from the aqueous solution and into the
fibers. Fibers such as cotton absorb water
readily and are said to be hydrophilic, while
fibers such as polyester absorb water with
difficulty and are described as hydrophobic.
Dyeability is influenced if a fiber can somehow carry an ionic charge and better interact with oppositely charged colored ions. To
dye cellulose, a reactive dye must combine
with the hydroxyl groups in the fiber.
Tie dyeing is one of the oldest methods of
printing designs on fabrics. Typically, parts
of the fabric are bunched together in a
design and knotted or tied together with
string. Tied sections are protected from
absorbing the dye and patterns are created.
Related Chemical Concepts:
Dyes, chrornophores, affinity (hydrophobic/hydrophilic).
covalent bonding vs.
adsorbtion, electrolyte concentration, equilibrium, kinetics, reaction rates (temperature effects, concentration effects), pH
Materials Needed and Preparation
• T-shirts, 100% cotton, PFD (prepared for
If you buy T-shirts that are not prepared
for dyeing, they must be pre-washed in
hot water with 2 tablespoons of a mild
detergent like Joy®, Dawn", Ivory", etc.
Do not use a detergent with phosphates
or chlorines. Dry shirts on the hot cycle
to remove spinning lubricants or other
surface additives.
• Sodium carbonate activator solution
For a class of 30 students you will need
approximately 8 liters of sodium carbonate activator solution. To prepare this
solution, mix 250 grams of sodium carbonate anhydrous into 8 liters of distilled
water and stir.
• Urea solution
For a class' of 30 students you will need
approximately 8 liters of Urea solution.
To prepare this solution, mix 650 grams
of urea into 8 liters of water and stir.
This solution can be stored if it is not
mixed with the reactive dye. Urea
increases the solubility of the heavy
shades of reactive dyes.
• Reactive Dyes
Place a small amount of cold water in a
beaker and add 4 to 6 teaspoons (12-18
grams) of the reactive dye you have
selected. Mix until lumps are removed
and all dye is moistened. Add urea solution (as described above) to make a total
of one liter of dye solution.
The amount of reactive dye is not specific
as it depends on how strong you want the
colors to be. Colors like yellow will need
more dye. Remember some of the dye
will wash out when the T-shirt is washed
in hot water, so make the color darker
than you want as an end product
Each student will require about one cup
of dye solution. For a class of 30 students, prepare a total of 2 liters <5freac- .
tive dye solution for each color you want
to use.
Reactive dyes should be stored at room
If kept dry, reactive dyes have a shelf life
of two years.
• Plastic bucket
• Plastic drop cloth
(Continued on page 2)
etc. This makes a great lab to do before
the Christmas holidays. Students can
make personalized gifts that are affordable. Use this activity as a fund raiser for
the science club at your school.
• Rubber bands! size 33 (3 1I2"L x 1/8"W)
.Jumbo, Beral-type pipets, 15 ml bulb
• Beakers, 1000 ml
• Oven racks or sturdy plastic coat hangers
interlocked between slats of wood
• Rubber gloves
• Ziplocksbags or small trash bags
• Newspaper
1. Fill the plastic bucket with 8 liters of
sodium carbonate activator solution.
Soak the T-shirts in the sodium carbonate activator solution for a minimum of
20 minutes. The ionization of cellulose
increases with increasing alkalinity of
the solution and above pH 8 there is an
adequate number of ionized hydroxyl
groups in the fiber for most dyeing purposes. Soaking the T-shirts for 2 hours
will maximize the number of possible
bonding sites. After the T-shirt has
soaked, wring the T-shirt out over the
plastic bucket.
The sodium carbonate activator solution
is very basic so be sure to wear rubber
gloves when placing shirts in the solution and when the shirt is wrung out at
the end of the activation period.
Figure 2
Hint This should be' done in an area separate from the dyeing area to prevent
shirts frompickingup
dye by mistake.
3. Dyeing can be done on oven racks placed
over sinks or on racks with newspaper
underneath to absorb' excess dye. After a
shirt is placed on a clean rack, dyes can
be applied using jumbo Beral-type
pipets. Apply the dye to one side of the
shirt by slowly squirting the reactive dye
solution onto each section of the shirt. A
beautiful design can be made by dyeing
each section of the shirt a .different
color. Once you are done dyeing one side
of the shirt, turn the shirt over and
repeat the dyeing process. Shirts should
drain for 15 minutes if possible.
Students tend to use a lot of dye and
there is a lot of dripping so be prepared.
Hint: Fewer beakers of dye and more
pipets work best. Too many beakers take
too long to clean up and reorganize
between classes. Shirts can pick up some
dye by mistake, but students will be
applying so much dye that it probably
will not matter. Clean work areas will
minimize problems.
2. Shirts are now ready to fold and tie. A
spiral pattern is created by laying the
shirt flat on a surface protected by a
clean dropcloth. The shirt is held with
the thumb and fingers at the point where
the center of the spiral will be located.
Use a twisting motion to coil the shirt
and use your other hand to bring the
loose ends of the shirt into the circle (see
Figure 1). Take four rubber bands and
slide them around the shirt so they intersect at the center where the twist began
(see Figure 2). You now have what
appears to look like a "pie" cut into eight
pieces. The bound shirt can be turned
over and dyed on both sides. We selected
this type of folding pattern because it is
the easiest to do and the entire tie-dyeing process can be completed in a 50minute lab period. Students also like this
pattern the best.
4. Place shirts in a plastic Ziplock" bag or
small trash bag and close to keep the
shirt moist. Drying will prevent the reactive dyes from fully reacting. Most colors
will have completely reacted after 4
hours but less reactive colors such as
green and turquoise will take as long as
24 hours. Be patient. Let the dyes react
5. At home, rinse the shirt in warm water
(75-900F) in order to remove the unreacted dye and the sodium carbonate activator. Change the water and continue to
rinse. Repeat until the water remains
clear and the shirt does not feel slippery.
Set the washing machine on the HOT
water setting and wash as many as 10
shirts at one time in 2 tablespoons of the
pre-wash, such as Joy® or Dawn" dishsoap. Dry shirts on the hottest dryer setting. The reactive dye is washfast so it is
now safe to wash with other clothes using
normal detergents. The reactive center on
the dyes is a dichloro-triazinyl group so
do not use bleaches on the shirt.
6. Now be creative! Try other patterns for
folding. Dye labcoats, socks, tennis shoes,
Safety Precautions:
Students should wear old clothes and
shoes. Reactive dyes are "wash fast." Once
the reactive dye makes contact with clothes
it will not wash out.
Do not let the students get sloppy.
Students should not squirt each other with
filled pipets of reactive dye solution.
Students should wear appropriate protective clothing, e.g., chemical splash goggles,
disposable plastic gloves and chemicalresistant aprons.
Hands may become stained from the reactive dye. It is not easily washed off and will
take about two days for the dye to wear off
your hands,
Sodium carbonate activator solution is
very basic. Be sure to wear rubber or plastic
gloves when placing the T-shirts in solution
and when the shirt is wrung out at the end
of the activation period.
All of the chemical solutions and reactive
dyes may be disposed of according to Flinn
Suggested Disposal Method #26b. Consult
your current Flinn Chemical Catalog/
Reference Manual.
Literature Cited:
American Association of Textile Chemists
and Colorists (MTCC). Dyeing Primer. A
series of short papers on the Fundamentals
of Dyeing. P.O. Box 12215, Research
Triangle Park, NC 27709.
Vickerstaff, T. "Theoretical Principles of
Dyeing with Reactive Dyes." Procion
Dyestuffin Textile Dyeing, 1962, pp. 17-40.
Special thanks to Gerald Blackstone,
Eastchester High School, Eastchester, NY
and Elenore Grow, Horizon High School,
Brighton, CO for showing me how to tie-dye.
Ordering information for Flinn's TieDyeing-Chemistry
Fun Kit is listed on
page 7 of this Flinn Fax. Individual tiedyeing supplies may be found below.
Pipets, Jumbo,
15 ml capacity,
Urea, 650 g
$ 9.50
Reactive Dye, Yellow,
45 grams
250 g
Reactive Dye, Red,
45 grams
Reactive Dye, Blue,
45 grams
Reactive Dye, Green,
45 grams