Polyester fiber

 

The British scientists John Whinfield and James Dickson first invented polyester cloth in 1941 in England. After World War II was over, in 1945, the United States company DuPont bought the right to make polyester and by 1950 a factory in Delaware was beginning to actually make it.

People make polyester out of oil. You take the oil, which is a kind of very big hydrocarbon molecule, and break it down into two smaller molecules, ethylene glycol and dimethyl naphthalate, both still made entirely of oxygen, carbon, andhydrogen atoms. Dimethyl terephthalate is an ester, and ethylene glycol is a kind of alcohol. When you mix the ester and the alcohol together, they form molecules with both positive and negative charges, and the charges make the molecules line up in chains of crystals that hold together as long fibers. 

The polymerized material comes out of the machine in long ribbons, and you cut the ribbons into little chips and let them harden. Then you melt the chips again and push the goo out through little holes to make thinner ribbons, and wind the thinner ribbons around spools. Then you heat the thinner ribbons and stretch them out to about five times their original length, to make them thin enough to use as thread to weave cloth. 

Since the 1960s, polyester has been the cheapest kind of cloth, and almost half of all the world's clothing is made of polyester. You are probably familiar with polyester mainly from team shirts like for soccer or basketball.
Polyester fiber is a " manufactured fiber in which the fiber forming substance is any long chain synthetic polymer composed at least 85% by weight of an ester of a dihydric alcohol (HOROH) and terephthalic acid (p-HOOC-C6H4COOH)" [3]. The most widely used polyester fiber is made from the linear polymer poly (ethylene terephtalate), and this polyester class is generally referred to simply as PET. High strength, high modulus, low _shrinkage, heat set stability, light fastness and chemical resistance account for the great versatility of PET.

These fibres are also known as Terylene, Terene, Dacron etc.

These fibres are synthetic textile fibres of high polymers which are obtained by esterification of dicarboxylic acids,

with glycols or by ester exchange reactions between dicarboxylic acid esters and glycols.

Thus Terylene is made by polymerising using ester exchange reation between dimethyl teraphthlate and ethylene glycol.


Raw Materials

The main raw materials required for the manufacture of Terylene polyester fibres are p-xylene ethylene glycol and methanol.or Dacron ( Du Pont ) is produced by polycondensation reaction using Teraphthaleic Acid (TPA) and Ethylene Glocol

Manufacture of TPA

P-xylene-- Air, nitric Acid-->P-Toluic Acid--> Teraphthaleic Acid

Manufacture of DMT

p-xylene--Air 200 degC, co-toluate--> Toluic Acid--Ch3OH--> Monomethyl toluate--oxidation--> Monomethyl teraphthalate--CH3OH--> DMT

The use of Dimethyl Teraphthalate is preferred instead of Teraphthalic acid as the purity of the reacting chemicals is essential and it is easier to purify DMT than teraphthalic acid.

Manufacture of Ethylene Glycol



Ethylene--Oxidation with air-->Ethylene Oxide--Hydrolysis-->Ethylene Glycol
or
Ethylene--Hypochlorous Acid HOCl--> Ethylene Chlorohydrin--Alkaline Hydrolysis--> Ethylene Glycol

Production
The polymer is made by heating teraphthalic acid with excess of ethylene glycol ( Both of high priority) in an atmosphere of nitrogen initially at atmospheric pressure. A catalyst like Hydrochloric acid speeds up the reaction.

The resulting low molecular weight ethylene glycol teraphthalate is then heated at 280 deg C for 30 minutes at atmospheric pressure and then for 10 hours under vacuum. The excess of ethylene glycol is distilled off. the ester can polymerise now to form a product of high molecular weight. The resulting polymer is hard and almost white substance, melting at 256 deg C and has a molecular weight of 8000-10000. Filaments are prepared from this.

Spinning of Polyester Fibres

The polymer is extruded in the form of a ribbon. This ribbon is then converted into chips.The wet chips are dried and fed through a hopper, ready for melting. This molten polymer is then extruded under high pressure through spinnerettes down to cylinder.

Each spinnerette contains 24 or so holes. A spinning finish is applied at this stage as a lubricant and an antistatic agent. The undrawn yarn is then wound onto cylinders.This yarn goes to the drawing zone, where draw twist machines draw it to about four times their original length. This is hot drawn in contrast to cold drawing of nylon filaments.
For the production of staple fibres, the filaments are first brought together to from a thick tow. These are distributed in large cans. The tow is drawn to get correct strength. Then it is passed through a crimping machines, the crimps being stabilized by heating in ovens. It is then cut into specified lengths and baled ready for dispatch.

Properties of Polyester

Tenacity (gpd)	High Tenacity	Normal Tenacity	Staple
Dry	6-7	4.5-5.5	3.5-4
Wet	6-7	4.5-5.5	3.5-4
Elongation (%)
Dry	12.5-7.5	25-15	40-25
Wet	12.5-7.5	25-15	40-25
Density	1.38	1.38	1.38

Moisture RegainAt 65% RH and 70 deg F--> 0.4%Because of low moisture regain, it develops static charge. Garments of polyester fibres get soiled easily during wear.

Thermal Properties

Polyester fibres are most thermally stable of all synthetic fibres. As with all thermoplastic fibres, its tenacity decreases and elongation increases with rise in temperature. When ignited, polyester fibre burns with difficulty.

Shrinkage

Polyester shrinks approx 7% when immersed in an unrestrained state in boiling water. Like other textile fibres, polyester fibres undergo degradation when exposed to sunlight.

Its biological resistance is good as it is not a nutrient for microorganisms.

Swelling and Dissolving

The fibre swells in 2% solution of benzoic acid salycylic acid and phenol.

Alcohols, Ketones, soaps, detergents and drycleaning solvents have no chemical action on polyester fibres.

Chemical Resistance

Polyester fibres have a high resistance to organic and mineral acids. Weak acids do not harm even at boil. Similarly strong acids including hydrofluoric acids do not attack the fibres appreciably in the cold.

CHEMICAL PROPERTIES
Polyester fibers have good resistance to weak mineral acids, even at boiling temperature, and to most strong acids at room temperature, but are dissolved with partial decomposition by concentrated sulfuric acid. Hydrolysis is highly dependent on temperature. Thus conventional PET fibers soaked in water at 70oC for several weeks do not show a measurable loss in strength, but after one week at 100oC, the strength is reduced by approximately 20%.


Polyesters are highly sensitive to bases such as sodium hydroxide and methylamine, which serve as catalysts in the hydrolysis reaction. Methylamine penetrates the structure initially through noncrystalline regions, causing the degradation of the ester linkages and, thereby, loss in physical properties. This susceptibility to alkaline attack is sometimes used to modify the fabric aesthetics during the finishing process. The porous structures produced on the fiber surface by this technique contribute to higher wettability and better wear properties [7].

Polyester displays excellent resistance to oxidizing agents, such as conventional textile bleaches, and is resistant to cleaning solvents and surfactants. Also, PET is insoluble in most solvents except for some polyhalogenated acetic acids and phenols. Concentrated solutions of benzoic acid and o-phenylphenol have a swelling effect.


PET is both hydrophobic and oleophilic. The hydrophobic nature imparts water repellency and rapid drying. But because of the oleophilic property, removal of oil stains is difficult. Under normal conditions, polyester fibers have a low moisture regain of around 0.4%, which contributes to good electrical insulating properties even at high temperatures. The tensile properties of the wet fiber are similar to those of dry fiber. The low moisture content, however, can lead to static problems that affect fabric processing and soiling.


 OPTICAL PROPERTIES

PET has optical characteristics of many thermoplastics, providing bright, shiny effects desirable for some end uses, such as silk-like apparel. Recently developed polyester microfiber with a linear density of less than 1.0 denier per filament (dpf), achieves the feel and luster of natural silk [23].

THERMAL PROPERTIES

The thermal properties of PET fibers depend on the method of manufacture. The DTA (Fig. 5.) and TMA (Fig. 6) data for fibers spun at different speeds show peaks corresponding to glass transition, crystallization, and melting regions. Their contours depend on the amorphous and crystalline content. The curves shown for 600 m/min and above are characteristic of drawn fiber. The glass transition range is usually in the range of 75^oC; crystallization and melting ranges are around 130^oC and 260^oC, respectively.

Uses of Polyester

1. Woven and Knitted Fabrics, especially blends.
2. Conveyor belts, tyre cords, tarpaulines etc.
3. For filling pillows
4. For paper making machine
5. Insulating tapes
6. Hose pipe with rubber or PVC
7. Ropes, fish netting and sail cloth.

BASIC WEAVES

1. Plain weave


The simplest of all patterns is the plain weave. Each weft yarn goes alternately over and under one warp yarn. Each warp yarn goes alternately over and under each weft yarn. Some examples of plain weave fabrics are crepe, taffeta, organdy and muslin. The plain weave may also have variations including the following:


Rib weave: the filling yarns are larger in diameter than the warp yarns. A rib weave produces fabrics in which fewer yarns per square centimeter are visible on the surface.
Matt Weave or Basket weave: here, two or more yarns are used in both the warp and filling direction. These groups of yarns are woven as one, producing a basket effect.
Interlaced with 1 warp yarn over first filling yarn and 1 warp yarn under next filling yarn forming each repeat. (1/1)
Look for an even repeat of yarns that looks like a checkerboard
Yields fabrics with: highest interlacing most raveling snag resistance most tendency for wrinkling lower tear strength Regular basket weave:
Irregular basket weave:



2. Twill weave:


Twill weave is characterized by diagonal ridges formed by the yarns, which are exposed on the surface. These may vary in angle from a low slope to a very steep slope. Twill weaves are more closely woven, heavier and stronger than weaves of comparable fiber and yarn size. They can be produced in fancy designs.
Interlaced with 2 or 3 warp yarns over and one or 2 warp yarns under respective filling yarns
Diagonal ridge formed left-to-right or right-to-left
fewer interlacing and therefore more yarns per inch
more raveling
more pliable drape and hand
more wrinkle resistance
more resistance to showing soil and soiling
more durability and heavier
tendency to have defined face and back
twill direction defined as left or right hand or variation
angle of twill can vary from 15¤ to 75¤ with 45¤ typicalIdentifying the Weave3. Satin weave
Structuring Process
Interlacing float over 4 or more yarns before a single interlacing (4/1, 7/1 or 11/1)
float in warp direction (satin), floats in filling direction (sateen)
Warp-faced fabric have vertical floats while filling-faced fabrics have horizontal floats
Shiny surface on float side if structured with smooth, shiny yarns
Flat, lustrous, smooth surface
Surface slides easily for linings
Floats result in fewest number of interlacing among plain, rib, twill weaves and therefore yield highest potential yarn count
Long floats (7/1, 11/1) and filament fabrics subject to snagging and poor abrasion resistance
Short floats (4/1, 1/4) and spun fabrics can be tough, compact, durable fabrics with low luster (sateen is formed with spun yarns, usually cotton)


Matt or Basket Weave


Basket weave is the amplification in height and width of plain weave. Two or more yarns have to be lifted or lowered over or under two or more picks for each plain weave point. When the groups of yarns are equal, the basket weave is termed regular, otherwise it is termed irregular.

This is commonly used for edges in drapery, or as a bottom in very small weave repeats, because the texture is too loose-fitting for big weave repeats; moreover, yarns of different groups can slip, group and overlap, spoiling the appearance. This is why only basket weaves 2-2, 3-3 and 4-4 exist


Satin weave

Satin weave is characterised by floating yarns, used to produce a high luster on one side of the fabric. Warp yarns of low twist float or pass over four or more filling yarns. Low twist and floating of warp yarns, together with fiber content, give a high degree of light reflection. Thanks to the distribution of interlacing points, all emphasized diagonal effects are avoided. As with twill, there is only one interlacing point on each thread and pick of the weave repeat. Satins differ from twills by having a step number different from 1.

Fabric defects

The finished fabrics can show various kind of faults which can be ascribed to the operations which

follow one another till the realization of the finished fabric. The most common defects which

appear in more or less extended areas of the fabric are:

·         Knot

·         crease mark

·         abrasion or hole

·         tear

·         stain

·         dirt contamination

·          moirè = presence of vawy areas in periodical sequence, reflecting the light and due to a

             different compression of weft or also of warp.

·         grain = presence of designs with streaked and sinuous lines.

The most common fabric defects due to warp are:

- Faulty thread = a thread or pieces of thread which are coarse, fine, irregular owing to higher or

lower twist or to other twist direction, of different colour, with two or three ends;

- missing thread = a thread or pieces of ground or effect threads which are missing in the fabric

weave;

- tight/slack thread = a thread or pieces of thread which are tighter or slacker than the other

pieces/threads;

- incorrectly woven yarn = a thread which in some parts only of the fabric is not interlaced in the

standard way

- broken warp = small pieces of cut or missing warp thread

- reversed thread = crossed, exchanged threads or thread pieces;

- warp stripes = one or more faulty threads giving rise to zones of different aspect; it can be due

to scraping or rubbing from members of production machines or to inaccurate reeding;

The most common fabric defects due to weft are:

·    Faulty weft = a weft or pieces of weft which are coarse, fine, irregular (slubs, etc.), twisted,

   reversed, with different twist, of different colour, double weft

·   missing weft = weft or pieces of weft missing in the fabric weave

·   tight/slack weft = a weft or pieces of weft which are tighter or slacker than the other

   pieces/wefts

·   incorrectly woven weft = a weft which in some parts only of the fabric is not interlaced in the       standard way

·   cut wefts = short pieces of cut wefts

·   weft bars (starting marks) = visual light/dark effect in weft direction due to higher or lower weft density caused by the weaving machine.

The quality control on the fabrics is carried out on a special inspecting machine, equipped with

special lamps which facilitate the defect detection by the operator, marks them with labels of

different colours according to the fault type and importance.

Depending on the number of faults and on their importance, the fabric pieces can be classified as

standard (in respect to quality specifications) or can be subjected to a more or less serious

degrading with consequent compensations to the customers or with the sale of the fabric at a

reduced price.

Various defects can arise during the stages of weaving preparation (warping, sizing, threading-in

into the heddles and into the reed) as well as during weaving itself. It is therefore important to

regulate accurately the various devices of the weaving machine and to understand how to act in

case of anomalous operating situations which create defects and/or reduce weaving efficiency.

Textile testing video

NATURAL DYEING OF TEXTILES

Introduction
Dyeing is an ancient art which predates written records. It was practised during the Bronze age in Europe. Primitive dyeing techniques included sticking plants to fabric or rubbing crushed pigments into cloth. The methods became more sophisticated with time and techniques using natural dyes from crushed fruits, berries and other plants, which were boiled into the fabric and gave light and water fastness (resistance), were developed.
Some of the well known ancient dyes include madder, a red dye made from the roots of the Rubia tinctorum, blue indigo from the leaves of Indigofera tinctoria, yellow from the stigmas of the saffron plant, and dogwood, an extract of pulp of the dogwood tree. The first use of the blue dye, woad, beloved by the Ancient Britons, may have originated in Palestine where it was found growing wild. The most famous and highly prized colour through the age was Tyrian purple, noted in the Bible, a dye obtained from the spiny dye-murex shellfish. The Phoenicians prepared it until the seventh century, when Arab conquerors destroyed their dyeing installations in the Levant. A bright red called cochineal was obtained from an insect native to Mexico. All these produced high-quality dark colours. Until the mid-19th century all dyestuffs were made from natural materials, mainly vegetable and animal matter.
Today, dyeing is a complex, specialised science. Nearly all dyestuffs are now produced from synthetic compounds. This means that costs have been greatly reduced and certain application and wear characteristics have been greatly enhanced. But many practitioners of the craft of natural dying (i.e. using naturally occurring sources of dye) maintain that natural dyes have a far superior aesthetic quality which is much more pleasing to the eye. On the other hand, many commercial practitioners feel that natural dyes are non-viable on grounds of both quality and economics. In the West, natural dyeing is now practised only as a handcraft, synthetic dyes being used in all commercial applications. Some craft spinners, weavers, and knitters use natural dyes as a particular feature of their work.
In many of the world’s developing countries, however, natural dyes can offer not only a rich and varied source of dyestuff, but also the possibility of an income through sustainable harvest and sale of these dye plants. Many dyes are available from tree waste or can be easily grown in market gardens. In areas where synthetic dyes, mordants (fixatives) and other additives are imported and therefore relatively expensive, natural dyes can offer an attractive alternative.


Dyeing of textiles Practical Action


The knowledge required for sourcing and extracting such dyes and mordants is, however, often not available as extensive research work is required to identify suitable plants, minerals, etc. In Zambia for example, there is a wealth of plants available for producing
natural dyes, but due to lack of knowledge of the processes involved in harvesting and processing the plants, little use is made of this natural resource. In some countries, such as India, Nigeria and Liberia, where this research has been carried out, or where there exists a tradition of natural dyeing, natural dyes and mordants are used widely.
Types of textiles suitable for dying
Natural dyes can be used on most types of material or fibre but the level of success in terms of fastness and clarity of colour varies considerably. Users of natural dyes, however, tend to also use natural fibres, and so we will look in more detail at this group. Natural fibres come mainly from two distinct origins, animal origin or vegetable origin. Fibres from an animal origin include wool, silk, mohair and alpaca, as well as some others which are less well known. All animal fibres are based on proteins. Natural dyes have a strong affinity to fibres of animal origin, especially wool, silk and mohair and the results with these fibres are usually good. Fibres of plant origin include cotton, flax or linen, ramie, jute, hemp and many others. Plant fibres have cellulose as their basic ingredient. Natural dyeing of certain plant based textiles can be less successful than their animal equivalent. Different mordanting techniques are called for with each category. When a blend of fibre of both animal and plant origin is being dyed, then a recipe should be chosen which will accentuate the fibre which is required to be dominant.
Equipment needed for home dyeing and very small-scale commercial dyeing
Most equipment needed for dyeing fabrics at home, or at the very small-scale commercial level, can be found in almost any market place throughout the world. The following is a list of the equipment requirements and a brief explanation of their use.

1.    • Heat source. This can be any type of cooking stove; gas, wood, kerosene, charcoal, electricity. This is used for heating the liquid used during mordanting and dyeing.

2.    • Pestle and mortar. Used for milling the natural dye or minerals, where this is called for.

3.    • Mordanting and dyeing pans. Stainless steel or enamel pans are the most suitable for dyeing. The size of pan depends upon the quantities of fabric that will be dyed. Do not use pans made from copper, aluminium or iron, unless absolutely necessary, as these metals have properties which can change the colour of the dye.

4.    • tirring rods. Stainless steel or glass rods are best as they can be cleaned and used for different colour dyes. If wooden stirring rods are used then there should be a different spoon for each colour.

5.    • Thermometer. This is used to measure the temperature of the liquid during mordanting and dyeing. A long thermometer (to reach the liquid at the bottom of the pan) is preferred, with a range of 0 – 100oC (32 – 210oF).

6.    • Measuring jugs. These are used to measure the quantities of liquid called for in the recipe. Sometimes precise quantities are called for.

7.    • Storage containers. Used for storing the dyestuffs and mordants. Large glass and plastic jars are ideal. Some mordants and dyes are sensitive to light and should therefore be stored in sealed light-proof containers.

8.    • Plastic bowls and buckets. A variety of plastic bowls or buckets of varying sizes are useful when wetting or rinsing fabrics.

9.    • Strainer. Used for straining the liquid off the dyestuff in the dyebath.

10.                       • Weighing scales. Used for obtaining the correct quantities as specified in the recipe. A scales with metric and imperial measurement is useful as conversions from one system to the other are not then needed.

11.                       • Protective equipment. Gloves for holding hot pans will prevent burns. An apron will protect your clothing. Rubber gloves will prevent skin irritation caused by mordants, and

2 Dyeing of textiles Practical Action

1.    will also prevent you from dyeing your hands. A face mask can cut down the amount of fumes or powder inhaled during the dyeing process.

Mordants
Few natural dyes are colour-fast with fibres. Mordants are substances which are used to fix a dye to the fibres. They also improve the take-up quality of the fabric and help improve colour and light-fastness. The term is derived from the Latin mordere, to bite. Some natural dyes, indigo for example, will fix without the aid of a mordant; these dyes are known as ‘substantive dyes’. Others dyes, such as madder and weld, have a limited fastness and the colour will fade with washing and exposure to light.
Traditionally, mordants were found in nature. Wood ash or stale urine may have been used as an alkali mordant, and acids could be found in acidic fruits or rhubarb leaves (which contain oxalic acid), for example. Nowadays most natural dyers use chemical mordants such as alum, copper sulphate, iron or chrome (there are concerns, however about the toxic nature of chrome and some practitioners recommend that it is not used).
Mordants are prepared in solution, often with the addition of an ‘assistant’ which improves the fixing of the mordant to the yarn or fibre. The most commonly used mordant is alum, which is usually used with cream of tartar as an additive or assistant. Other mordants are:

1.    • Iron (ferrous sulphate)

2.    • Tin (stannous chloride)

3.    • Chrome (bichromate of potash)

4.    • Copper sulphate

5.    • Tannic acid

6.    • Oxalic acid

Using a different mordant with the same dyestuff can produce different shades, for example;

1.    • Iron is used as a ‘saddener’ and is used to darken colours.

2.    • Copper sulphate also darkens but can give shades which are otherwise very difficult to obtain.

3.    • Tin brightens colours.

4.    • Tannic acid, used traditionally with other mordants, will add brilliancy.

5.    • Chrome is good for obtaining yellows.

6.    • Oxalic acid is good for extracting blues from berries.

7.    • Cream of Tartar is not really a mordant but is used to give a lustre to wool.

Mordants are often poisonous, and in the dye-house they should be kept on a high shelf out of the reach of children. Always use protective clothing when working with mordants and avoid breathing the fumes.
The mordant can be added before, during or after the dyeing stage, although most recipes call for mordanting to take place prior to dyeing. It is best to follow the instructions given in the recipe being used or experiment on a sample before carrying out the final dyeing. Later in this brief we will explain how the mordant is mixed and used as part of the dyeing process.
These chemical mordants are usually obtained from specialist suppliers or from chemists. Where this is prohibitive, due to location or cost, natural mordants can be used. There are
3 Dyeing of textiles Practical Action
a number of plants and minerals which will yield a suitable mordant, but their availability will be dependent upon your surroundings. Some common substitutes for a selection of mordants are listed below.

1.    • Some plants, such as mosses and tea, contain a small amount of aluminium. This can be used as a substitute to alum. It is difficult to know, however, how much aluminium will be present and experimentation may be necessary.

2.    • Iron water can be used as a substitute to ferrous sulphate. This can be made simply by adding some rusty nails and a cupful of vinegar to a bucket-full of water and allowing the mixture to sit for a couple of weeks.

3.    • Oak galls or sumach leaves can be used a substitute to tannic acid.

4.    • Rhubarb leaves contain oxalic acid.

Natural dyestuffs
Dyestuffs and dyeing are as old as textiles themselves. Nature provides a wealth of plants which will yield their colour for the purpose of dyeing, many having been used since antiquity. In this section we will look at some of these naturally occurring dyes, their source and the colours they produce. Later in the brief we will look at the application of the dyes to textiles.
Almost any organic material will produce a colour when boiled in a dye-bath, but only certain plants will yield a colour that will act as a dye. The plants given in Table 1 are a selection of plants that have stood the test of time, and are used widely and traditionally by natural dyers. Natural dyes fall into the following categories:

1.    • Leaves and stems

2.    • Twigs and prunings

3.    • Flower heads

4.    • Barks

5.    • Roots

6.    • Outer skins, hulls and husks

7.    • Heartwoods and wood shavings

8.    • Berries and seeds

9.    • Lichens

10.                       • Insect dyes

Figure 2: Marigold

Common Name	Latin Name	Parts Used	General Colour Guide	Suggested Mordant
Alder	Alnus spp	Bark	Yellow/ brown/ black	Alum, iron. Copper sulphate
Alkanet	Anchusa tinctoria	Root	Grey	Alum, cream of tartar
Apple	Malus spp	Bark	Yellow	Alum
Blackberry	Rubus spp	Berries, young	Pink,	Alum, tin

4 Dyeing of textiles Practical Action

shoots				Purple
Betel nut		Areca catechu		Nut		Deep pink
Blackwillow	Salix negra		Bark		Red, brown		Iron
Bloodroot	Sanguinaria canadensis		Roots		Red		Alum, tin
Buckthorn	Rhammus cathartica		Twigs, berries, bark		Yellow, brown		Alum, cream of tartar, tin, iron
Cherry (wild)	Prunus spp		Bark		Pink, yellow, brown		Alum
Dahlia	Dahlia spp		Petals		Yellow bronze		Alum
Dog’s mercury	Mercurialis perennis		Whole plant		Yellow		Alum
Dyer’s broom	Genista tinctoria		Flowering tops		Yellow		Alum
Elder	Sambucus negra		Leaves, berreis, bark		Yellow, grey		Iron, alum
Eucalyptus		Eucalyptus		Leaves		Deep gold, grey
Fustic		Chloropho-ria tinctoria		Wood shavings		Yellow
Groundnut	Arachis hypogea		Kernel skins		Purple, brown, pink		Copper sulphate, alum
Henna		Lawsonia inermis		Leaves		Gold
Hypogymnia lichen		Hypogymnia psychodes		Whole lichen		Gold, brown
Indigo	Indigofera		Leaves		Blue		Not required
Ivy	Hedera helix		Berries		Yellow, green		Alum, tin
Madder	Rubia tinctora		Whole plant		Orange, red		Alum, tin
Maple	Acer spp		Bark		Tan		Copper sulphate
Marigold	Calendual spp		Whole plant, flower heads		Yellow		Alum
Nettles	Urtica dioica		Leaves		Beige, yellowy greens		Alum, copper
Onion	Allium cepa		Skins		Yellow, orange		Alum
Oak	Quercus spp		Inner bark		Gold, brown		Alum
Ochrolech-ina lichen	Ochrolech-ina parella		Whole lichen		Orange, red (when fermanted in urine then boiled)		Alum
Privet	Ligustrum vulgare		Leaves, berries		Yellow, green, red, purple		Alum, tin
Ragwort		Senecio		Flowers		Deep yellow
Safflower	Carthamus tinctoria		Petals		Yellow, red		Alum
Sloe- Blackthorn	Prunus spinosa		Sloe berries, bark		Red, pink, brown		Alum
Tea		Camelia sinensis		Leaves		Beige
Turmeric		Circuma longa		Root		Yellow
Wild mangosteen		Diospyros peregrina		Fruit		Grey, pink
Weld (wild mignonette)	Reseda luteula		Whole plant		Olive green		Alum, cream of tartar
Woad	Isatis tinctoria		Whole plant		Blue		Lime

Table 1. A list of plants commonly used for preparing dyes.
The choice of mordant for a particular plant is dependant upon the material with which it will be used. It is necessary to check a recipe before using a plant, or one can experiment to see what effect a mordant has for a particular application.
It is recommended that plants be grown specifically for the purpose of dyeing. Harvesting plants from the wild on a non-sustainable basis can endanger the survival of the plant. Many lichens are registered as protected organisms and it is illegal to gather them from the wild.