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//-->NATURAL DYEINGOF TEXTILESIntroductionDyeing is an ancient art which predates written records. It was practised during the Bronzeage in Europe. Primitive dyeing techniques included sticking plants to fabric or rubbingcrushed pigments into cloth. The methods became more sophisticated with time andtechniques using natural dyes from crushed fruits, berries and other plants, which wereboiled 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 oftheRubia tinctorum,blue indigo from the leaves ofIndigofera tinctoria,yellow from thestigmas of the saffron plant, and dogwood, an extract of pulp of the dogwood tree. The firstuse of the blue dye, woad, beloved by the Ancient Britons,may have originated in Palestine where it was foundgrowing wild. The most famous and highly prized colourthrough the age was Tyrian purple, noted in the Bible, a dyeobtained from the spiny dye-murex shellfish. ThePhoenicians prepared it until the seventh century, whenArab conquerors destroyed their dyeing installations in theLevant. A bright red called cochineal was obtained from aninsect native to Mexico. All these produced high-qualitydark colours. Until the mid-19th century all dyestuffs weremade from natural materials, mainly vegetable and animalmatter.Today, dyeing is a complex, specialised science. Nearly alldyestuffs are now produced from synthetic compounds.This means that costs have been greatly reduced andcertain application and wear characteristics have beengreatly enhanced. But many practitioners of the craft ofnatural dying (i.e. using naturally occurring sources of dye)maintain that natural dyes have a far superior aestheticquality which is much more pleasing to the eye. On theother hand, many commercial practitioners feel that naturaldyes are non-viable on grounds of both quality andeconomics. In the West, natural dyeing is now practisedonly as a handcraft, synthetic dyes being used in allcommercial applications. Some craft spinners, weavers,and knitters use natural dyes as a particular feature of their work.Figure 1: IndigoIn many of the world’s developing countries, however, natural dyes can offer not only a richand varied source of dyestuff, but also the possibility of an income through sustainableharvest and sale of these dye plants. Many dyes are available from tree waste or can beeasily grown in market gardens. In areas where synthetic dyes, mordants (fixatives) andother additives are imported and therefore relatively expensive, natural dyes can offer anattractive alternative.Dyeing of textilesPractical ActionThe 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 producingnatural dyes, but due to lack of knowledge of the processes involved in harvesting andprocessing the plants, little use is made of this natural resource. In some countries, such asIndia, Nigeria and Liberia, where this research has been carried out, or where there exists atradition of natural dyeing, natural dyes and mordants are used widely.Types of textiles suitable for dyingNatural dyes can be used on most types of material or fibre but the level of success in termsof fastness and clarity of colour varies considerably. Users of natural dyes, however, tend toalso use natural fibres, and so we will look in more detail at this group. Natural fibres comemainly from two distinct origins, animal origin or vegetable origin. Fibres from an animalorigin include wool, silk, mohair and alpaca, as well as some others which are less wellknown. All animal fibres are based on proteins. Natural dyes have a strong affinity to fibres ofanimal origin, especially wool, silk and mohair and the results with these fibres are usuallygood. 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 basedtextiles can be less successful than their animal equivalent. Different mordanting techniquesare called for with each category. When a blend of fibre of both animal and plant origin isbeing dyed, then a recipe should be chosen which will accentuate the fibre which is requiredto be dominant.Equipment needed for home dyeing and very small-scale commercialdyeingMost equipment needed for dyeing fabrics at home, or at the very small-scale commerciallevel, can be found in almost any market place throughout the world. The following is a list ofthe equipment requirements and a brief explanation of their use.•••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.Pestle and mortar.Used for milling the natural dye or minerals, where this is called for.Mordanting and dyeing pans.Stainless steel or enamel pans are the most suitable fordyeing. The size of pan depends upon the quantities of fabric that will be dyed. Do notuse pans made from copper, aluminium or iron, unless absolutely necessary, as thesemetals have properties which can change the colour of the dye.tirring rods.Stainless steel or glass rods are best as they can be cleaned and used fordifferent colour dyes. If wooden stirring rods are used then there should be a differentspoon for each colour.Thermometer.This is used to measure the temperature of the liquid during mordantingand dyeing. A long thermometer (to reach the liquid at the bottom of the pan) isoopreferred, with a range of 0 – 100 C (32 – 210 F).Measuring jugs.These are used to measure the quantities of liquid called for in therecipe. Sometimes precise quantities are called for.Storage containers.Used for storing the dyestuffs and mordants. Large glass and plasticjars are ideal. Some mordants and dyes are sensitive to light and should therefore bestored in sealed light-proof containers.Plastic bowls and buckets.A variety of plastic bowls or buckets of varying sizes areuseful when wetting or rinsing fabrics.Strainer.Used for straining the liquid off the dyestuff in the dyebath.Weighing scales.Used for obtaining the correct quantities as specified in the recipe. Ascales with metric and imperial measurement is useful as conversions from one systemto the other are not then needed.Protective equipment.Gloves for holding hot pans will prevent burns. An apron willprotect your clothing. Rubber gloves will prevent skin irritation caused by mordants, and••••••••2Dyeing of textilesPractical Actionwill also prevent you from dyeing your hands. A face mask can cut down the amount offumes or powder inhaled during the dyeing process.MordantsFew natural dyes are colour-fast with fibres. Mordants are substances which are used tofix a dye to the fibres. They also improve the take-up quality of the fabric and help improvecolour and light-fastness. The term is derived from the Latinmordere,to bite. Some naturaldyes, 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 thecolour will fade with washing and exposure to light.Traditionally, mordants were found in nature. Wood ash or stale urine may have been usedas an alkali mordant, and acids could be found in acidic fruits or rhubarb leaves (whichcontain oxalic acid), for example. Nowadays most natural dyers use chemical mordantssuch as alum, copper sulphate, iron or chrome (there are concerns, however about thetoxic 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 improvesthe 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:••••••Iron (ferrous sulphate)Tin (stannous chloride)Chrome (bichromate of potash)Copper sulphateTannic acidOxalic acidUsing a different mordant with the same dyestuff can produce different shades, forexample;•••••••Ironis used as a ‘saddener’ and is used to darken colours.Copper sulphatealso darkens but can give shades which are otherwise very difficult toobtain.Tinbrightens colours.Tannic acid,used traditionally with other mordants, will add brilliancy.Chromeis good for obtaining yellows.Oxalic acidis good for extracting blues from berries.Cream of Tartaris 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 shelfout of the reach of children. Always use protective clothing when working with mordantsand avoid breathing the fumes.The mordant can be added before, during or after the dyeing stage, although most recipescall for mordanting to take place prior to dyeing. It is best to follow the instructions given inthe recipe being used or experiment on a sample before carrying out the final dyeing. Laterin this brief we will explain how the mordant is mixed and used as part of the dyeingprocess.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 are3Dyeing of textilesPractical Actiona number of plants and minerals which will yield a suitable mordant, but their availabilitywill be dependent upon your surroundings. Some common substitutes for a selection ofmordants are listed below.•Some plants, such as mosses and tea, contain a small amount of aluminium. This canbe used as a substitute to alum. It is difficult to know, however, how much aluminiumwill be present and experimentation may be necessary.Iron water can be used as a substitute to ferrous sulphate. This can be made simplyby adding some rusty nails and a cupful of vinegar to a bucket-full of water andallowing the mixture to sit for a couple of weeks.Oak galls or sumach leaves can be used a substitute to tannic acid.Rhubarb leaves contain oxalic acid.•••Natural dyestuffsDyestuffs and dyeing are as old as textilesthemselves. Nature provides a wealth ofplants which will yield their colour for thepurpose of dyeing, many having been usedsince antiquity. In this section we will look atsome of these naturally occurring dyes, theirsource and the colours they produce. Laterin the brief we will look at the application ofthe dyes to textiles.Almost any organic material will produce acolour when boiled in a dye-bath, but onlycertain plants will yield a colour that will actas a dye. The plants given in Table 1 are aselection of plants that have stood the test oftime, and are used widely and traditionallyby natural dyers. Natural dyes fall into thefollowing categories:••••••••••Leaves and stemsTwigs and pruningsFlower headsBarksRootsOuter skins, hulls and husksHeartwoods and wood shavingsBerries and seedsLichensInsect dyesLatin NameAlnus sppAnchusatinctoriaMalus sppRubus sppParts UsedBarkRootBarkBerries, youngFigure 2: MarigoldCommonNameAlderAlkanetAppleBlackberryGeneral Colour GuideYellow/ brown/ blackGreyYellowPink,SuggestedMordantAlum, iron.Copper sulphateAlum, cream oftartarAlumAlum, tin4Dyeing of textilesPractical ActionBetel nutBlackwillowBloodrootBuckthornCherry (wild)DahliaDog’s mercuryDyer’s broomElderEucalyptusFusticGroundnutHennaHypogymnialichenIndigoIvyMadderMapleMarigoldNettlesOnionOakOchrolech-inalichenPrivetRagwortSafflowerSloe-BlackthornTeaTurmericWildmangosteenWeld (wildmignonette)WoadAreca catechuSalix negraSanguinariacanadensisRhammuscatharticaPrunus sppDahlia sppMercurialisperennisGenistatinctoriaSambucusnegraEucalyptusChloropho-riatinctoriaArachishypogeaLawsoniainermisHypogymniapsychodesIndigoferaHedera helixRubia tinctoraAcer sppCalendual sppUrtica dioicaAllium cepaQuercus sppOchrolech-inaparellaLigustrumvulgareSenecioCarthamustinctoriaPrunusspinosaCameliasinensisCircuma longaDiospyrosperegrinaReseda luteulaIsatis tinctoriashootsNutBarkRootsTwigs, berries,barkBarkPetalsWhole plantFlowering topsLeaves, berreis,barkLeavesWood shavingsKernel skinsLeavesWhole lichenLeavesBerriesWhole plantBarkWhole plant,flower headsLeavesSkinsInner barkWhole lichenLeaves, berriesFlowersPetalsSloe berries,barkLeavesRootFruitWhole plantWhole plantPurpleDeep pinkRed, brownRedYellow, brownPink, yellow, brownYellow bronzeYellowYellowYellow, greyDeep gold, greyYellowPurple, brown, pinkGoldGold, brownBlueYellow, greenOrange, redTanYellowBeige, yellowy greensYellow, orangeGold, brownOrange, red (whenfermanted in urine thenboiled)Yellow, green, red, purpleDeep yellowYellow, redRed, pink, brownBeigeYellowGrey, pinkOlive greenBlueIronAlum, tinAlum, cream oftartar, tin, ironAlumAlumAlumAlumIron, alumCopper sulphate,alumNot requiredAlum, tinAlum, tinCopper sulphateAlumAlum, copperAlumAlumAlumAlum, tinAlumAlumAlum, cream oftartarLimeTable 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 itwill be used. It is necessary to check a recipe before using a plant, or one can experimentto see what effect a mordant has for aparticular application.It is recommended that plants be grownspecifically for the purpose of dyeing.Harvesting plants from the wild on a non-sustainable basis can endanger the survivalof the plant. Many lichens are registered asprotected organisms and it is illegal togather them from the wild. One source of5Figure 3:Groundnuts [ Pobierz całość w formacie PDF ]
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//-->NATURAL DYEINGOF TEXTILESIntroductionDyeing is an ancient art which predates written records. It was practised during the Bronzeage in Europe. Primitive dyeing techniques included sticking plants to fabric or rubbingcrushed pigments into cloth. The methods became more sophisticated with time andtechniques using natural dyes from crushed fruits, berries and other plants, which wereboiled 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 oftheRubia tinctorum,blue indigo from the leaves ofIndigofera tinctoria,yellow from thestigmas of the saffron plant, and dogwood, an extract of pulp of the dogwood tree. The firstuse of the blue dye, woad, beloved by the Ancient Britons,may have originated in Palestine where it was foundgrowing wild. The most famous and highly prized colourthrough the age was Tyrian purple, noted in the Bible, a dyeobtained from the spiny dye-murex shellfish. ThePhoenicians prepared it until the seventh century, whenArab conquerors destroyed their dyeing installations in theLevant. A bright red called cochineal was obtained from aninsect native to Mexico. All these produced high-qualitydark colours. Until the mid-19th century all dyestuffs weremade from natural materials, mainly vegetable and animalmatter.Today, dyeing is a complex, specialised science. Nearly alldyestuffs are now produced from synthetic compounds.This means that costs have been greatly reduced andcertain application and wear characteristics have beengreatly enhanced. But many practitioners of the craft ofnatural dying (i.e. using naturally occurring sources of dye)maintain that natural dyes have a far superior aestheticquality which is much more pleasing to the eye. On theother hand, many commercial practitioners feel that naturaldyes are non-viable on grounds of both quality andeconomics. In the West, natural dyeing is now practisedonly as a handcraft, synthetic dyes being used in allcommercial applications. Some craft spinners, weavers,and knitters use natural dyes as a particular feature of their work.Figure 1: IndigoIn many of the world’s developing countries, however, natural dyes can offer not only a richand varied source of dyestuff, but also the possibility of an income through sustainableharvest and sale of these dye plants. Many dyes are available from tree waste or can beeasily grown in market gardens. In areas where synthetic dyes, mordants (fixatives) andother additives are imported and therefore relatively expensive, natural dyes can offer anattractive alternative.Dyeing of textilesPractical ActionThe 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 producingnatural dyes, but due to lack of knowledge of the processes involved in harvesting andprocessing the plants, little use is made of this natural resource. In some countries, such asIndia, Nigeria and Liberia, where this research has been carried out, or where there exists atradition of natural dyeing, natural dyes and mordants are used widely.Types of textiles suitable for dyingNatural dyes can be used on most types of material or fibre but the level of success in termsof fastness and clarity of colour varies considerably. Users of natural dyes, however, tend toalso use natural fibres, and so we will look in more detail at this group. Natural fibres comemainly from two distinct origins, animal origin or vegetable origin. Fibres from an animalorigin include wool, silk, mohair and alpaca, as well as some others which are less wellknown. All animal fibres are based on proteins. Natural dyes have a strong affinity to fibres ofanimal origin, especially wool, silk and mohair and the results with these fibres are usuallygood. 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 basedtextiles can be less successful than their animal equivalent. Different mordanting techniquesare called for with each category. When a blend of fibre of both animal and plant origin isbeing dyed, then a recipe should be chosen which will accentuate the fibre which is requiredto be dominant.Equipment needed for home dyeing and very small-scale commercialdyeingMost equipment needed for dyeing fabrics at home, or at the very small-scale commerciallevel, can be found in almost any market place throughout the world. The following is a list ofthe equipment requirements and a brief explanation of their use.•••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.Pestle and mortar.Used for milling the natural dye or minerals, where this is called for.Mordanting and dyeing pans.Stainless steel or enamel pans are the most suitable fordyeing. The size of pan depends upon the quantities of fabric that will be dyed. Do notuse pans made from copper, aluminium or iron, unless absolutely necessary, as thesemetals have properties which can change the colour of the dye.tirring rods.Stainless steel or glass rods are best as they can be cleaned and used fordifferent colour dyes. If wooden stirring rods are used then there should be a differentspoon for each colour.Thermometer.This is used to measure the temperature of the liquid during mordantingand dyeing. A long thermometer (to reach the liquid at the bottom of the pan) isoopreferred, with a range of 0 – 100 C (32 – 210 F).Measuring jugs.These are used to measure the quantities of liquid called for in therecipe. Sometimes precise quantities are called for.Storage containers.Used for storing the dyestuffs and mordants. Large glass and plasticjars are ideal. Some mordants and dyes are sensitive to light and should therefore bestored in sealed light-proof containers.Plastic bowls and buckets.A variety of plastic bowls or buckets of varying sizes areuseful when wetting or rinsing fabrics.Strainer.Used for straining the liquid off the dyestuff in the dyebath.Weighing scales.Used for obtaining the correct quantities as specified in the recipe. Ascales with metric and imperial measurement is useful as conversions from one systemto the other are not then needed.Protective equipment.Gloves for holding hot pans will prevent burns. An apron willprotect your clothing. Rubber gloves will prevent skin irritation caused by mordants, and••••••••2Dyeing of textilesPractical Actionwill also prevent you from dyeing your hands. A face mask can cut down the amount offumes or powder inhaled during the dyeing process.MordantsFew natural dyes are colour-fast with fibres. Mordants are substances which are used tofix a dye to the fibres. They also improve the take-up quality of the fabric and help improvecolour and light-fastness. The term is derived from the Latinmordere,to bite. Some naturaldyes, 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 thecolour will fade with washing and exposure to light.Traditionally, mordants were found in nature. Wood ash or stale urine may have been usedas an alkali mordant, and acids could be found in acidic fruits or rhubarb leaves (whichcontain oxalic acid), for example. Nowadays most natural dyers use chemical mordantssuch as alum, copper sulphate, iron or chrome (there are concerns, however about thetoxic 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 improvesthe 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:••••••Iron (ferrous sulphate)Tin (stannous chloride)Chrome (bichromate of potash)Copper sulphateTannic acidOxalic acidUsing a different mordant with the same dyestuff can produce different shades, forexample;•••••••Ironis used as a ‘saddener’ and is used to darken colours.Copper sulphatealso darkens but can give shades which are otherwise very difficult toobtain.Tinbrightens colours.Tannic acid,used traditionally with other mordants, will add brilliancy.Chromeis good for obtaining yellows.Oxalic acidis good for extracting blues from berries.Cream of Tartaris 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 shelfout of the reach of children. Always use protective clothing when working with mordantsand avoid breathing the fumes.The mordant can be added before, during or after the dyeing stage, although most recipescall for mordanting to take place prior to dyeing. It is best to follow the instructions given inthe recipe being used or experiment on a sample before carrying out the final dyeing. Laterin this brief we will explain how the mordant is mixed and used as part of the dyeingprocess.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 are3Dyeing of textilesPractical Actiona number of plants and minerals which will yield a suitable mordant, but their availabilitywill be dependent upon your surroundings. Some common substitutes for a selection ofmordants are listed below.•Some plants, such as mosses and tea, contain a small amount of aluminium. This canbe used as a substitute to alum. It is difficult to know, however, how much aluminiumwill be present and experimentation may be necessary.Iron water can be used as a substitute to ferrous sulphate. This can be made simplyby adding some rusty nails and a cupful of vinegar to a bucket-full of water andallowing the mixture to sit for a couple of weeks.Oak galls or sumach leaves can be used a substitute to tannic acid.Rhubarb leaves contain oxalic acid.•••Natural dyestuffsDyestuffs and dyeing are as old as textilesthemselves. Nature provides a wealth ofplants which will yield their colour for thepurpose of dyeing, many having been usedsince antiquity. In this section we will look atsome of these naturally occurring dyes, theirsource and the colours they produce. Laterin the brief we will look at the application ofthe dyes to textiles.Almost any organic material will produce acolour when boiled in a dye-bath, but onlycertain plants will yield a colour that will actas a dye. The plants given in Table 1 are aselection of plants that have stood the test oftime, and are used widely and traditionallyby natural dyers. Natural dyes fall into thefollowing categories:••••••••••Leaves and stemsTwigs and pruningsFlower headsBarksRootsOuter skins, hulls and husksHeartwoods and wood shavingsBerries and seedsLichensInsect dyesLatin NameAlnus sppAnchusatinctoriaMalus sppRubus sppParts UsedBarkRootBarkBerries, youngFigure 2: MarigoldCommonNameAlderAlkanetAppleBlackberryGeneral Colour GuideYellow/ brown/ blackGreyYellowPink,SuggestedMordantAlum, iron.Copper sulphateAlum, cream oftartarAlumAlum, tin4Dyeing of textilesPractical ActionBetel nutBlackwillowBloodrootBuckthornCherry (wild)DahliaDog’s mercuryDyer’s broomElderEucalyptusFusticGroundnutHennaHypogymnialichenIndigoIvyMadderMapleMarigoldNettlesOnionOakOchrolech-inalichenPrivetRagwortSafflowerSloe-BlackthornTeaTurmericWildmangosteenWeld (wildmignonette)WoadAreca catechuSalix negraSanguinariacanadensisRhammuscatharticaPrunus sppDahlia sppMercurialisperennisGenistatinctoriaSambucusnegraEucalyptusChloropho-riatinctoriaArachishypogeaLawsoniainermisHypogymniapsychodesIndigoferaHedera helixRubia tinctoraAcer sppCalendual sppUrtica dioicaAllium cepaQuercus sppOchrolech-inaparellaLigustrumvulgareSenecioCarthamustinctoriaPrunusspinosaCameliasinensisCircuma longaDiospyrosperegrinaReseda luteulaIsatis tinctoriashootsNutBarkRootsTwigs, berries,barkBarkPetalsWhole plantFlowering topsLeaves, berreis,barkLeavesWood shavingsKernel skinsLeavesWhole lichenLeavesBerriesWhole plantBarkWhole plant,flower headsLeavesSkinsInner barkWhole lichenLeaves, berriesFlowersPetalsSloe berries,barkLeavesRootFruitWhole plantWhole plantPurpleDeep pinkRed, brownRedYellow, brownPink, yellow, brownYellow bronzeYellowYellowYellow, greyDeep gold, greyYellowPurple, brown, pinkGoldGold, brownBlueYellow, greenOrange, redTanYellowBeige, yellowy greensYellow, orangeGold, brownOrange, red (whenfermanted in urine thenboiled)Yellow, green, red, purpleDeep yellowYellow, redRed, pink, brownBeigeYellowGrey, pinkOlive greenBlueIronAlum, tinAlum, cream oftartar, tin, ironAlumAlumAlumAlumIron, alumCopper sulphate,alumNot requiredAlum, tinAlum, tinCopper sulphateAlumAlum, copperAlumAlumAlumAlum, tinAlumAlumAlum, cream oftartarLimeTable 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 itwill be used. It is necessary to check a recipe before using a plant, or one can experimentto see what effect a mordant has for aparticular application.It is recommended that plants be grownspecifically for the purpose of dyeing.Harvesting plants from the wild on a non-sustainable basis can endanger the survivalof the plant. Many lichens are registered asprotected organisms and it is illegal togather them from the wild. One source of5Figure 3:Groundnuts [ Pobierz całość w formacie PDF ]