general details about natural dyes

1. Presented by
S.Krishnam Raju
141la11013
3rd year
Textile technology
Vignan University.

2. Introduction
Nowadays the environment aspects of effluent treatment are too complicated problems in
processing industries. So due to overcome this problem, now a day’s eco-friendly process
is required. If we used the natural coloring matters with ecofriendly process, there is no
need of effluent treatment. Natural dyes are eco-friendly to the environment. All natural
dyes are not having good fixation to material.
Natural dyes:
Natural dyes are dyes or colorants derived from plants, invertebrates, or minerals. The
majority of natural dyes are vegetable dyes from plant sources –roots, berries, bark, leaves,
and wood—and other organic sources such as fungi and lichens.
Dyeing Processes
The essential process of dyeing requires soaking the material containing the dye(the
dyestuff)in water, adding the textile to be dyed to the resulting solution (the dye bath), and
bringing the solution to a simmer for an extended period, often measured in days or even
weeks, stirring occasionally until the color has evenly transferred to the textiles.[9]
Direct Dye
Some dyestuffs, such as indigo and lichens, will give good color when used alone; these
dyes are called direct dyes or substantive dyes.
Mordant Dye
The majority of plant dyes, however, also require the use of a mordant, a chemical used to
"fix" the color in the textile fibers. These dyes are called adjective dyes.
Mordant
In traditional dyeing, the common mordents are
1. Vinegar,
2. Tannin from oak bark, sumac or oak galls,
3. Ammonia from stale urine,

3. 4. Wood ash or stale urine may have been used as an Alkali mordant.
5. Rhubarb leaves (which contain oxalic acid) Acidic mordant
6. Iron water can be used as a substitute to ferrous sulphate
7. Some plants, such as mosses and tea, contain a small amount of aluminum. This can be
used as a substitute to alum.
Common Natural dyes and its origin

4. Advantages of Natural Dyes:
1) Health and safety aspects of natural dyes: Though all natural dyes are not 100% safe
they are less toxic than their synthetic counterparts. Many of the natural dyes like turmeric,
annatto and saffron are permitted as food additives. Many natural dyes have
pharmacological effects and possible health benefits.
2) They are obtained from renewable sources.
3) Natural dyes cause no disposal problems, as they are biodegradable.
4) Practically no or mild reactions are involved in their preparation.
5) They are unsophisticated and harmonized with nature.
6) Many natural dyes have the advantage that even though they have poor wash fastness
ratings, they do not stain the adjacent fabrics in the washing process because of the non-
substantive nature of the dye towards the fabric. An exception to this is turmeric, which
shows substantively for cotton.
7) Natural dyes are cost effective

5. 8) It is possible to obtain a full range of colors using various mordents.
Types and Methods
Alum:
 Available in most grocery stores and very safe to use; it's normal to add cream of
tartar to produce brighter, cleaner colors.
 Dissolve the Alum (about 3 oz. per pound of fabric or yarn and 1 oz. cream of
tartar) separately in warm water.
 Pour into a water bath of 4 gallons of water, heated to 160°. Add your fabric being
careful not to crowd.
 Bring to a slow boil in about 30 minutes and then hold at that level of boil for 45
minutes.
 Your fabric will take a better dye if you allow it to cool in the bath.
 You can use it immediately, or let it dry.
 Chemical name: potassium aluminum sulfate.
Chrome:
 This gives wonderful deep, rich colors.
 You have to be more careful with it, then the alum, to avoid uneven coloring later
on.
 Adding cream of tartar will help brighten the colors even more. Use 1/2 oz. of
chrome with 4 gallons of water, to 1 pound of fabric or yarn.
 Heat the water to 160°, and remember to pre-dissolve the chrome in warm water
first. Put your wet, washed fabric in the bath and simmer for 30 minutes.
 Remove the fabric, add 1/2 oz. of cream of tartar (pre-dissolved) stir thoroughly,
replace the fabric and simmer for 1 hour.
 Be careful to keep the fabric totally under the water in the bath, or when you do
dye your fabric it will streak.
 Wash the fabric after mordanting in the chrome and allow it to dry slowly, before
dying.
 If you're going to be dyeing the fabric lighter colors, you can use a bit less chrome.
 Too much will result in a harsher feel to the fabric?
 Chemical name: potassium dichromate.
Tin:
 The most difficult of all the mordents metallic to use.

6.  Too much will destroy your fabric or yarn. Its greatest use is as an aid to other
mordents, with bright, crisp yellows and reds resulting.
 As an actual mordant, use 1/2 oz. tin, with 2 oz. cream of tartar and 3/4 oz. oxalic
acid - to one pound fabric or yarn in 4 gallons of water.
 Heat the water to 140°, put in the wet, washed fabric and raise the temperature of
the bath to 190°. Hold at that level for 1 hour. Do Not Boil.
 Chemical name: stannous chloride, tin crystals. Oxalic acid is Oxalic wood sorrel,
a bleaching or cleaning agent - very strong acid.
Dyeing procedure
Example:
Recipe for dyeing wool with onion skins
Fabric: applicable to wool or other animal (protein) fibers.

7. You will need:
• 100 grams of natural wool
• 30 grams of onion skins (use only the dry, brown, outer skins)
• 8 grams of alum (the mordant)
• 7 grams cream of tartar (the assistant)
• Some liquid detergent (the scouring agent)
• A water supply
2. Yellow Onion skins on alum mordant wool

8. You will need:
 Yellow Onion skins on heuchera mordant wool.
 Yellow Onion skins and garlic skins on unmordanted wool.
 Yellow Onion skins and garlic skins on alum mordant wool.
 Red Onion skins on unmordanted wool.
 Red Onion skins on alum mordant wool.
 Red Onion skins on heuchera mordant wool.
Dyeing with Bougainvillea

Applications
Ayurvastra
 Ayurveda is a traditional and the most influential form of medicine native to India
originating from its Vedic traditions.
 Ayurvastra is a fabric that is dyed as prescribed in the Ayurveda texts, using various
natural herbs like neem, Talsi, sida, turmeric, and sandalwood.
 These fabrics are permeated with therapeutic herbs, and aromatic oils. They possess
medicinal properties, and are good for skin problems, headache, asthma, and many
other ailment
Antimicrobial Effect on Annatto Treated Material
Our cloth is producing pathogenic odor, bacteria, fungi and moulds. They include a variety
of microorganisms like bacteria, algae, fungi and virus. Microbes require certain conditions
to grow including dirt, perspiration, warm environment moisture and a receipting surface

9. like skin or fabrics. Textiles are carriers of microorganisms such as pathogenic bacteria,
odor generating bacterial, mould and fungi Annatto is a natural carotenoid obtained from
Bixa Orellana shrub. In Recent Years, the seeds are gaining economic importance as a
highly desirable colorant. The ripe fruits of annatto on drying yield annatto seed which
serves as the raw material for the production of annatto color. The coloring matter is
collected from the outer part of the seed. Annatto dye is non – toxic and is mainly used for
coloring edible products. It is used for only the purpose of coloring edible items like butter,
ghee, chocolates. Annatto is also used as an ingredients in medicine to cure fevers,
dysentery and kidney diseases. Now, it is mostly used to color the medicine like tablets and
capsule. And it is used to produce ointments for curing wounds. In India, it used as an insect
repellant.
It is a natural dye obtained from annatto tree. Annatto possess good substantive towards
cotton material and give orange color. If we use mordant means there is a chance of getting
color from light orange to orange red. It gives pleasant odor to textile material. Natural
herbal products can be used for antimicrobial composition to be the effective candidates in
bringing out herbal textiles. The plants and plant products are traditionally used for healing
Plant Profile:
Family Bixaceae
English name Arnott or Annatto plant
Indian name  Sindarin (Sanskrit)
 Sinduriya, Latkan (Hindi)
 Rang male (Kannada)
 Uragumanjal (Tamil)
Species Bixa Orellana

10. of wounds, burn-injuries and antimicrobial activity against skin infections. Several
medicinal plants are used for years in treating many diseases in daily life. Plants are reliable
source of potentially important bioactive natural products. The growing interest in herbs
and economically useful plant is part of the movement towards green economical life style.
Extraction of Annatto:
Annatto extracts can be found in many forms. It may be a power, paste, oil or as a chunk.
It can also be used in food for culinary enhancements and flavoring. The procedure to make
any of them is a little time taking as well as tedious. If annatto seeds are being used as it is,
it is not really tough. The seeds have a coating of an oily paste that coating bixin. Bixin is
a yellow orange carotenoid. It is extracted using aqueous alkaline solution and vegetable
oil solvent.
Vegetable oil solvent gives oil soluble bixin; alkaline solution gives water soluble norbixin
and propylene glycol yields a combination. For powder form, annatto seeds need to be
dried and cursed to extract the powder. Deriving the paste form needs addition of water,
vinegar and other herbs too at times. Annatto oil is available in flavored as well as
unflavored form. It needs putting a little bit of edible oil in annatto seeds. It is basically
reddish orange colored oil. Annatto oil is quite popular primarily in South America and it
is used for cooking in a number of cuisines.
Uses of Annatto
 Mainly Latin American cuisines traditionally use annatto in recipes of Spanish
origin that originally call for saffron; for example, in Arroz con Polo, to give the
rice a yellow color.
 In Venezuela, annatto (called locally onoto) is used in the preparation of halluces,
perico, and other traditionally dishes.

11.  In Brazil, both annatto (the product) and the tree are called urucum and the product
itself may also be called color au. In the Caribbean islands, both fruit and tree are
popularly called achiote or bija instead of Bixa.
 Annatto has been linked with many cases of food- related allergies, and is the only
natural food coloring. Because it is a natural colorant, companies using annatto may
label their products, “all natural colors” on the principal display panel (PDP).
 IT’S well known that synthetic food color, expressly some azo dyes, can provoke
hypersensitivity reaction such as urticarial, antineurotic edema, and asthma
(Michaelson and Julian, 1973, granola and Thune, 1975).
 Natural food colors are scarcely investigated with respect to potential allergic
properties. Annatto extract, a commonly used food color in edible fats e.g. butter,
has been tested in patients. Among 61 consecutive patients suffering from chronic
urticarial and/or antineurotic edema 56 patients were orally provoked by annatto
extract during elimination diet.
 Calling was performed with a dose equivalent to the amount used in 25gm of
butter.26% of patients reacted to this color 4hour after intake. Similar challenges
with synthetic dyes showed the following result.
As a Food Coloring
 The water soluble part is called norbixin, the fat soluble part of the crude extract is
called bixin and both share the same E number as annatto. Annatto seed contains
4.5-5.5% pigments, which consists of 70 – 80% bixin.
 In the United States, annatto extract is listed as a color additive “exempt from
certification” and is informally considered to be natural color. The yellowish orange
color. The yellowish orange color is produced by the chemical compounds bixin
and norbixin which are classified as carotenoids. They do not have the correct
chemical structures to be vitamin A precursors unlike beta-carotene which is
another well-known carotenoid.
 A higher level of bixin gives it a more reddish shade; the more norbixin in an
annatto color, the more yellow it is. It takes on a pink shade at low pH, unless an
acid-proof version is used.
 Annatto has been linked with many cases of food-related allergies. It is the only
natural food coloring believed to cause as many allergic-type reactions as artificial
food coloring.

12. Materials and Methods:
Cotton fabric is used for applying the annatto dyes .The cotton fabric is soft fluffy stable
fiber, so the fabric when it placed on the surface of the skin our body gets feel cool,
relaxation, and feel so breathe freely.
Testing Methods:
1. Rubbing Fastness.
2. Washing Fastness
3.Anti-microbial test
Testing:
1. Rubbing fastness:
 To determine the fastness of the dyed material due to rubbing of the material.
 Two tests are prescribed, one with a dry rubbing cloth and the other with a wet
rubbing cloth.
 Evaluate the degree of staining of the piece of undyed cloth with the geometric grey
scale (staining) and assign the ratings.
2. Washing Durability:
 To determine the effect of washing fastness to the annatto dyed fabric.
 A specimen of textile in contact with species of specified adjacent fabric is
mechanically agitated in soap solution, rinsed and dried.

13.  The change in color of the specimen and the staining of the adjacent fabrics are
assessed with the standard grey scale.
3. Anti-microbial testing:
 The term Anti-microbial points to a broad range of technologies that provide
varying degrees of protection for products and buildings against microorganisms.
So the annatto dyed material is analyzed for anti- microbial activity.
 The test method is carried out using AATCC test method 147-1993, 1996(parallel
streak method).
Novel technologies in antimicrobial finishing are successfully employed in non-woven
sector especially in medical the bioactive fibers includes sanitary materials, surgical
threads, dressing materials and materials for filtration of gases and liquids, air conditioning
and ventilation, and special materials for food industry also. The Ultimate goal of this is to
create a color to the fabric and that will kill microbes’. But maintain all necessary textile
properties including durability and comfort properties.
References:
1. Collins, P. (1991). Annatto legislation in Europe. In: Proceedings of 1st
International symposium on Annatto; Campinas, Brazil; 17-21 June 1991; edited
by Carvalho, P.R.N. and Yabiku, H.Y. Campinas, Brazil: Instituto de Technology
de Alimentos.
2. Didrikson, C. (1991). Annatto on the European market. In: Proceedings of 1st
International Symposium on Annatto (see under Collins, P.).
3. International Trade Centre (1993). Annatto Seeds: Export Opportunities for the
Andean Region. Geneva: International Trade Centre.
4. Preston, H.D. and Rickard, M.D. (1980). Extraction and chemistry of annatto. Food
Chemistry, 5, 47-56.
5. Venter, M.W. (1981). The cultivation of Bixa Orellana (L.). Crop Production
(South Africa), 5(10), 87-89.
6. Wood, A.B. et al. (1991). Bikinied assay in annatto seed and its extracts: an
evaluation of methods and recommendations for sample handling. Paper presented
by Natural Resources Institute at the 1st Int. Symposium on Annatto, Campinas
Brazil, June 1991.