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{{short description|Soluble chemical substance or natural material which can impart color to other materials}}
{{other uses}}
[[File:Childhood Joy.jpg|thumb|upright=1.35|Drying colored cloth]]
[[File:Indigo skeletal.svg|thumb|Chemical structure of [[indigo dye]], the blue coloration of blue jeans. Although once extracted from plants, indigo dye is now almost exclusively synthesized industrially.<ref name=Ullmann>{{Ullmann|last=Steingruber |first=Elmar|title=Indigo and Indigo Colorants|doi=10.1002/14356007.a14_149.pub2}}</ref>]]

A '''dye''' is a [[wiktionary:colored|color]]ed substance that chemically bonds to the [[wikt:material|material]] to which it is being applied. This distinguishes dyes from [[pigment]]s which do not chemically bind to the material they color. Dye is generally applied in an [[aqueous solution]] and may require a [[mordant]] to improve the fastness of the dye on the fiber.<ref name="Ullmann's Encyclopedia of Industrial Chemistry">{{Ullmann|last=Booth|first=Gerald|title=Dyes, General Survey |doi=10.1002/14356007.a09_073}}</ref>

The majority of [[natural dye]]s are derived from non-animal sources such as roots, berries, bark, leaves, wood, fungi and [[lichen]]s.<ref>{{cite book|url=https://books.google.com/books?id=8CwxW75P_dsC&q=natural+organic+dye+textbook|title=Harvesting Color: How to Find Plants and Make Natural Dyes|first=Rebecca|last=Burgess|date=8 November 2017|publisher=Artisan Books|access-date=8 November 2017|via=Google Books|isbn=9781579654252}}</ref> However, due to large-scale demand and technological improvements, most dyes used in the modern world are synthetically produced from substances such as petrochemicals.<ref>{{Britannica URL |title=Synthetic dyes |url=technology/dye/Synthetic-dyes }}</ref> 
Some are extracted from [[insect]]s and/or [[mineral]]s.<ref>{{Cite book |last=Kassinger |first=Ruth |url=http://archive.org/details/dyesfromseasnail0000kass |title=Dyes : from sea snails to synthetics |date=2003 |location=Brookfield, Conn. |publisher= Twenty-First Century Books |via=Internet Archive |isbn=978-0-7613-2112-5}}</ref>

Synthetic dyes are produced from various chemicals. The great majority of dyes are obtained in this way because of their superior cost, optical properties (color), and resilience (fastness, mordancy).<ref name="Ullmann's Encyclopedia of Industrial Chemistry"/> Both dyes and pigments are colored, because they absorb only some wavelengths of visible [[light]]. Dyes are usually soluble in some solvent, whereas pigments are insoluble. Some dyes can be [[Precipitation (chemistry)|rendered insoluble]] with the addition of [[salt (chemistry)|salt]] to produce a [[lake pigment]].

==History==
[[File:Dyeing British Library Royal MS 15.E.iii, f. 269 1482.jpg|right|thumb|Dyeing wool cloth, 1482: from a French translation of [[Bartolomaeus Anglicus]]]]

[[Textile]] dyeing dates back to the [[Neolithic]] period. Throughout history, people have dyed their textiles using common, locally available materials. Scarce dyestuffs that produced brilliant and permanent colors such as the natural invertebrate dyes [[Tyrian purple]] and crimson [[kermes (dye)|kermes]] were highly prized luxury items in the ancient and medieval world. Plant-based dyes such as [[isatis tinctoria|woad]], [[Indigo dye|indigo]], [[Saffron (use)|saffron]], and [[rubia|madder]] were important trade goods in the economies of Asia and Europe. Across Asia and Africa, patterned fabrics were produced using [[resist dyeing]] techniques to control the absorption of color in piece-dyed cloth. Dyes from the [[New World]] such as [[cochineal]] and [[Haematoxylum campechianum|logwood]] were brought to Europe by the [[Spain|Spanish]] treasure fleets,<ref>{{cite book|chapter-url=https://books.google.com/books?id=89Qs0uba9VAC&q=dyes+brought+to+europe+from+spain&pg=PA29|title=Lasers in the Conservation of Artworks: Proceedings of the International Conference Lacona VII, Madrid, Spain, 17 - 21 September 2007|editor-first1=Marta|editor-last1=Castillejo|editor-first2=Pablo|editor-last2=Moreno|editor-first3=Mohamed|editor-last3=Oujja|editor-first4=Roxana|editor-last4=Radvan|editor-first5=Javier|editor-last5=Ruiz|display-editors=3|date=15 August 2008|publisher=CRC Press|access-date=8 November 2017|via=Google Books|isbn=9780203882085| chapter=Study of laccaic acid and other natural anthraquinone dyes by Surface-Enhanced Raman Scattering spectroscopy |last1=Cañamares |first1=M. V. |last2=Leona |first2=M. |pages=29–33}}</ref> and the dyestuffs of Europe were carried by colonists to America.<ref>{{cite book|url=https://books.google.com/books?id=EElNckPn0FUC&q=dyestuffs+carried+to+america+by+colonists&pg=PA45|title=Natural Dyes and Home Dyeing (formerly Titled: Natural Dyes in the United States)|first=Rita J.|last=Adrosko|date=8 November 1971|publisher=Courier Corporation|access-date=8 November 2017|via=Google Books|isbn=9780486226880}}</ref>

Dyed [[flax]] fibers have been found in the [[Georgia (country)|Republic of Georgia]] in a prehistoric cave dated to 36,000 [[Before Present|BP]].<ref>{{cite journal |last1=Balter |first1=Michael |title=Clothes Make the (Hu) Man |journal=Science |date=11 September 2009 |volume=325 |issue=5946 |pages=1329 |doi=10.1126/science.325_1329a |pmid=19745126 }}</ref><ref>{{cite journal |last1=Kvavadze |first1=Eliso |last2=Bar-Yosef |first2=Ofer |last3=Belfer-Cohen |first3=Anna |last4=Boaretto |first4=Elisabetta |last5=Jakeli |first5=Nino |last6=Matskevich |first6=Zinovi |last7=Meshveliani |first7=Tengiz |title=30,000-Year-Old Wild Flax Fibers |journal=Science |date=11 September 2009 |volume=325 |issue=5946 |pages=1359 |doi=10.1126/science.1175404 |pmid=19745144 |bibcode=2009Sci...325.1359K |url=https://nrs.harvard.edu/urn-3:HUL.InstRepos:4270521 |url-access=subscription }}</ref> [[Archaeology|Archaeological]] evidence shows that, particularly in [[India]] and [[Phoenicia]], [[dyeing]] has been widely carried out for over 5,000 years. Early dyes were obtained from [[animal]], [[vegetable]] or [[mineral]] sources, with no to very little processing. By far the greatest source of dyes has been from the [[plant kingdom]], notably roots, berries, bark, leaves and wood, only few of which are used on a commercial scale.<ref>{{Cite book |title=The Art and Craft of Natural Dyeing |last=Liles |first=J.N |publisher=University of Tennessee Press |year=1990 |isbn=9780870496707 |pages=2–4 |url=https://books.google.com/books?id=VUW-l1Wg1wYC|quote= "..By 1500 в.с. the Phoenicians had a thriving Tyrian (royal) purple dye industry in Tyre and other cities. Among the ancients, India was probably the most advanced. The Indians dyed all natural fibers well, especially the more complicated and time-consuming cotton...".}}</ref>

Early industrialization was conducted by [[J. Pullar and Sons]] in Scotland.<ref name=reader>{{cite news |url=https://www.pressreader.com/uk/the-courier-advertiser-fife-edition/20160607/282772060836523 |title=John Pullar (1803–1878) |newspaper=The Courier & Advertiser |date=7 June 2016}}</ref> The first synthetic dye, [[mauveine|mauve]], was discovered [[serendipity|serendipitously]] by [[William Henry Perkin]] in 1856.<ref>{{cite journal |last1=Hübner |first1=Karl |title=150 Jahre Mauvein |journal=Chemie in unserer Zeit |date=August 2006 |volume=40 |issue=4 |pages=274–275 |doi=10.1002/ciuz.200690054 }}</ref><ref>{{cite journal |last1=Travis |first1=Anthony S. |title=Perkin's Mauve: Ancestor of the Organic Chemical Industry |journal=Technology and Culture |date=1990 |volume=31 |issue=1 |pages=51–82 |doi=10.2307/3105760 |jstor=3105760 }}</ref><ref name="Murray1999">{{cite journal |last1=Eiland |first1=Murray Lee |title=Problems Associated with the Dissemination of Synthetic Dyes in the Oriental Carpet Industry |journal=Icon |date=1999 |volume=5 |pages=138–159 |jstor=23786082 }}</ref> The discovery of mauveine started a surge in synthetic dyes and in organic chemistry in general. Other [[aniline]] dyes followed, such as [[fuchsine]], [[safranine]], and [[induline]]. Many thousands of synthetic dyes have since been prepared.<ref>{{cite book |editor-last=Hunger |editor-first=K. |year=2003 |title=Industrial Dyes: Chemistry, Properties, Applications |location=Weinheim |publisher=Wiley-VCH | isbn=978-3-527-30426-4 | doi=10.1002/3527602011}}{{pn|date=October 2024}}</ref><ref>{{cite book |last=Zollinger |first=H. |year=2003 |title=Color Chemistry: Synthesis, Properties and Applications of Organic Dyes and Pigments |edition=3rd |location=Weinheim |publisher=Wiley-VCH | isbn=978-3-906390-23-9}}{{pn|date=October 2024}}</ref>

The discovery of [[mauveine]] in 1856 led to the development of a synthetic dyestuff industry. In Manchester, England, a number of people set up dyestuff manufacturing plant including [[Ivan Levinstein]], [[Levinstein Ltd]],<ref>1908 Stock Exchange Year-Book </ref> [[Charles Dreyfus]], [[Clayton Aniline Company]],<ref>1908 Stock Exchange Year-Book</ref> William Claus, Claus & co.<ref>ICI Dyestuffs Division and predecessor companies archive Claus & Co. Held at University of Manchester Library</ref>

The discovery of mauve also led to developments within [[immunology]] and [[chemotherapy]]. In 1863 the forerunner to [[Bayer AG]] was formed in what became [[Wuppertal]], [[Germany]]. In 1891, [[Paul Ehrlich]] discovered that certain cells or organisms took up certain dyes selectively. He then reasoned that a sufficiently large dose could be injected to kill pathogenic microorganisms, if the dye did not affect other cells. Ehrlich went on to use a compound to target [[syphilis]], the first time a chemical was used in order to selectively kill bacteria in the body. He also used [[methylene blue]] to target the [[plasmodium]] responsible for [[malaria]].<ref>{{cite book |last1=Burrows |first1=Andy |last2=Holman |first2=John |last3=Parsons |first3=Andy |last4=Pilling |first4=Gwen |last5=Price |first5=Gareth |title=Chemistry³: Introducing inorganic, organic and physical chemistry |date=2009 |publisher=OUP Oxford |isbn=978-0-19-927789-6 |pages=1005–1006 }}</ref>

[[File:Blick in Farbstoffsammlung 01.JPG|thumb|Historical collection of over 10,000 dyes at [[Technical University Dresden]], [[Germany]]]]

== Chemistry ==
The color of a dye is dependent upon the ability of the substance to absorb light within the visible region of the electromagnetic spectrum (380–750&nbsp;nm). An earlier theory known as Witt theory stated that a colored dye had two components, a [[chromophore]] which imparts color by absorbing light in the visible region (some examples are [[Nitro compound|nitro]], [[Azo compound|azo]], [[quinoid]] groups) and an [[auxochrome]] which serves to deepen the color. This theory has been superseded by modern electronic structure theory which states that the color in dyes is due to excitation of valence [[π-electron]]s by visible light.<ref>{{cite journal |last1=Bafana |first1=Amit |last2=Devi |first2=Sivanesan Saravana |last3=Chakrabarti |first3=Tapan |title=Azo dyes: past, present and the future |journal=Environmental Reviews |date=December 2011 |volume=19 |issue=NA |pages=350–371 |doi=10.1139/a11-018 |bibcode=2011EnvRv..19..350B }}</ref>

==Types==
[[File:RITdye.JPG|thumb|RIT brand dye from mid-20th century Mexico, part of the permanent collection of the [[Museo del Objeto del Objeto]]]]
[[File:Hårfärgning - 2007.jpg|thumb|A [[woman]] dyeing her [[hair]]]]
Dyes are classified according to their solubility and chemical properties.<ref name="Ullmann's Encyclopedia of Industrial Chemistry"/>

'''[[Acid dye]]s''' are [[water]]-[[soluble]] [[anionic]] dyes that are applied to [[fiber]]s such as [[silk]], [[wool]], [[nylon]] and modified [[acrylic fiber]]s using neutral to acid dye baths. Attachment to the fiber is attributed, at least partly, to salt formation between anionic groups in the dyes and [[cationic]] groups in the fiber. Acid dyes are not substantive to [[Cellulose|cellulosic]] fibers. Most synthetic food colors fall in this category. Examples of acid dye are Alizarine Pure Blue B, [[Acid red 88]], etc.

'''Basic dyes''' are water-soluble [[cationic]] dyes that are mainly applied to [[acrylic fiber]]s, but find some use for wool and silk. Usually [[acetic acid]] is added to the dye bath to help the uptake of the dye onto the fiber. Basic dyes are also used in the coloration of [[paper]].

'''Direct''' or '''[[substantive dye]]ing''' is normally carried out in a neutral or slightly [[alkaline]] dye bath, at or near [[boiling point]], with the addition of either [[sodium chloride]] (NaCl) or [[sodium sulfate]] (Na<sub>2</sub>SO<sub>4</sub>) or [[sodium carbonate]] (Na<sub>2</sub>CO<sub>3</sub>). Direct dyes are used on [[cotton]], paper, [[leather]], wool, silk and [[nylon]]. They are also used as [[pH indicator]]s and as [[staining (biology)|biological stains]].

[[organic dye laser|Laser dyes]] are used in the production of some lasers, optical media ([[CD-R#ORGANIC DYE|CD-R]]), and [[camera sensors]] ([[color filter array]]).<ref>{{cite book|url=https://books.google.com/books?id=_F4hAwAAQBAJ&q=organic+dye+laser&pg=PA539|title=Laser Fundamentals|first=William T.|last=Silfvast|date=21 July 2008|publisher=Cambridge University Press|access-date=8 November 2017|via=Google Books|isbn=9781139855570}}</ref>

'''[[Mordant dye]]s''' require a [[mordant]], which improves the fastness of the dye against water, [[light]] and [[perspiration]]. The choice of mordant is very important as different mordants can change the final color significantly. Most natural dyes are mordant dyes and there is therefore a large literature base describing dyeing techniques. The most important mordant dyes are the synthetic mordant dyes, or chrome dyes, used for wool; these comprise some 30% of dyes used for wool, and are especially useful for black and navy shades. The mordant [[potassium dichromate]] is applied as an after-treatment. It is important to note that many mordants, particularly those in the heavy metal category, can be hazardous to health and extreme care must be taken in using them.

'''[[Vat dye]]s''' are essentially insoluble in water and incapable of dyeing fibres directly. However, reduction in [[alkaline liquor]] produces the water-soluble [[alkali]] [[metal]] [[salt]] of the dye. This form is often colorless, in which case it is referred to as a [[leuco dye]], and has an affinity for the textile fibre. Subsequent [[oxidation]] reforms the original insoluble dye. The color of denim is due to [[Indigo dye|indigo]], the original vat dye.

'''[[Reactive dyes]]''' utilize a [[chromophore]] attached to a [[substituent]] that is capable of directly [[chemical reaction|reacting]] with the fiber substrate. The [[covalent]] bonds that attach reactive dye to natural fibers make them among the most permanent of dyes. "Cold" reactive dyes, such as [[Procion MX]], [[Cibacron F]], and [[Drimarene K]], are very easy to use because the dye can be applied at room temperature. Reactive dyes are by far the best choice for dyeing [[cotton]] and other [[cellulose]] fibers at home or in the art studio.

'''[[Disperse dye]]s''' were originally developed for the dyeing of [[cellulose acetate]], and are water-insoluble. The dyes are finely ground in the presence of a dispersing agent and sold as a paste, or spray-dried and sold as a powder. Their main use is to dye [[polyester]], but they can also be used to dye nylon, [[cellulose triacetate]], and acrylic fibers. In some cases, a dyeing [[temperature]] of {{convert|130|C|F}} is required, and a pressurized dyebath is used. The very fine particle size gives a large surface area that aids dissolution to allow uptake by the fiber. The dyeing rate can be significantly influenced by the choice of dispersing agent used during the grinding.

'''Azoic dyeing''' is a technique in which an insoluble [[azo dye]] is produced directly onto or within the fiber. This is achieved by treating a fiber with both diazoic and coupling [[wikt:component|components]]. With suitable adjustment of dyebath conditions the two components react to produce the required insoluble azo dye. This technique of dyeing is unique, in that the final color is controlled by the choice of the diazoic and coupling components. This method of dyeing cotton is declining in importance due to the toxic nature of the chemicals used.

'''[[Sulfur dye]]s''' are inexpensive dyes used to dye cotton with dark colors. Dyeing is effected by heating the fabric in a solution of an organic compound, typically a nitrophenol derivative, and sulfide or [[polysulfide]]. The organic compound reacts with the sulfide source to form dark colors that adhere to the fabric. Sulfur Black 1, the largest selling dye by volume, does not have a well defined chemical structure.

'''Some dyes commonly used in Staining:''' 
{| class="wikitable"
|+
!Basic dyes
!Acidic dyes
|-
|[[Safranin]]
|[[Eosin]]
|-
|[[Fuchsine|Basic fuchsin]]
|[[Acid fuchsin]] 
|-
|[[Crystal violet]]
|[[Congo red]]
|-
|[[Methylene blue]]
|
|}
{{clear}}

==Food dyes==
One other class that describes the role of dyes, rather than their mode of use, is the [[food coloring|food dye]]. Because food dyes are classed as [[food additive]]s, they are manufactured to a higher standard than some industrial dyes. Food dyes can be direct, mordant and vat dyes, and their use is strictly controlled by [[law|legislation]]. Many are [[Azo compound|azo]] dyes, although [[anthraquinone]] and [[triphenylmethane]] compounds are used for colors such as [[green]] and [[blue]]. Some naturally occurring dyes are also used.<ref>{{cite journal |last1=Rodriguez-Amaya |first1=Delia B |title=Natural food pigments and colorants |journal=Current Opinion in Food Science |date=February 2016 |volume=7 |pages=20–26 |doi=10.1016/j.cofs.2015.08.004 }}</ref>

==Other important dyes==
A number of other classes have also been established, including:
* Oxidation bases, for mainly hair and fur
* [[Laser dye]]s: [[rhodamine 6G]] and [[coumarin]] dyes.<ref>{{cite book |editor1-first = F. J. |editor1-last=Duarte |editor1-link=F. J. Duarte |editor2-first=L. W. |editor2-last=Hillman |title=Dye Laser Principles |location=New York |date=1990}}</ref>
* [[Leather]] dyes, for leather
* [[Fluorescent brightener]]s, for textile fibres and paper
* [[Solvent dye]]s, for wood staining and producing colored lacquers, solvent inks, coloring oils, waxes.
* Contrast dyes, injected for magnetic resonance imaging, are essentially the same as clothing dye except they are coupled to an agent that has strong paramagnetic properties.<ref>{{cite web|url=http://www.patentstorm.us/patents/6123921/description.html|title=patentstorm.us|website=Patentstorm.us|access-date=8 November 2017|archive-url=https://web.archive.org/web/20110612104958/http://www.patentstorm.us/patents/6123921/description.html|archive-date=12 June 2011|url-status=dead}}</ref>
* Mayhems dye, used in water cooling for looks, often rebranded RIT dye

==Chromophoric dyes==
By the nature of their [[chromophore]], dyes are divided into:<ref>{{cite web|url=http://stainsfile.info/StainsFile/dyes/dyes.htm|title=Stainsfile - Dye index|first=Bryan D.|last=Llewellyn|website=Stainsfile.info|access-date=8 November 2017|archive-url=https://web.archive.org/web/20080416165706/http://stainsfile.info/StainsFile/dyes/dyes.htm|archive-date=16 April 2008|url-status=dead}}</ref>
* [[:Category:Acridine dyes]], derivates of [[acridine]]
* [[:Category:Anthraquinone dyes]], derivates of [[anthraquinone]]
* Arylmethane dyes
** [[:Category:Diarylmethane dyes]], based on diphenyl methane
** [[:Category:Triarylmethane dyes]], derivates of [[triphenylmethane]]
* [[:Category:Azo dyes]], based on -N=N- [[azo compound|azo]] structure
* Phthalocyanine dyes, derivatives of [[phthalocyanine]]
* Quinone-imine dyes, derivatives of [[quinone]]
** [[:Category:Azin dyes]]
*** [[:Category:Eurhodin dyes]]
*** [[:Category:Safranin dyes|Category:Safranih]]
*** [[:Category:Safranin dyes|dyes]], derivates of [[safranin]]
** Indamins
** [[:Category:Indophenol dyes]], derivates of indophenol
** [[:Category:Oxazin dyes]], derivates of oxazin
** Oxazone dyes, derivates of [[Nile red|oxazone]]
** [[:Category:Thiazine dyes]]
* [[:Category:Thiazole dyes]]
* [[:Category:Safranin dyes]]
* [[Xanthene#Xanthene dyes|Xanthene dyes]]
** Fluorene dyes, derivatives of [[fluorene]]
*** [[Pyronin]] dyes
** [[:Category:Fluorone dyes]], based on [[fluorone]]
*** [[:Category:Rhodamine dyes]], derivatives of [[rhodamine]]

== Pollution ==
{{Merge from|Industrial dye degradation|discuss=Talk:Industrial dye degradation#Merge proposal|date=November 2025}}
Dyes produced by the textile, printing and paper industries are a source of pollution of rivers and waterways.<ref name=Brindley2009>{{cite news |last= Brindley |first=Lewis |date=July 2009 |title= New solution for dye wastewater pollution |url= https://www.chemistryworld.com/news/new-solution-for-dye-wastewater-pollution/3002870.article|work= [[Chemistry World]]|access-date=2018-07-08 }}</ref> An estimated 700,000 tons of dyestuffs are produced annually (1990 data). The disposal of that material has received much attention, using chemical and biological means.<ref>{{cite journal|doi=10.1016/j.chemosphere.2004.07.030|title=Degradation of dyes in aqueous solutions by the Fenton process|year=2004|last1=Xu|first1=Xiang-Rong|last2=Li|first2=Hua-Bin|last3=Wang|first3=Wen-Hua|last4=Gu|first4=Ji-Dong|journal=Chemosphere|volume=57|issue=7|pages=595–600|pmid=15488921|bibcode=2004Chmsp..57..595X|url=http://ir.rcees.ac.cn/handle/311016/23586|url-access=subscription}}</ref>

==Vital dyes==
A "vital dye" or stain is a dye capable of penetrating living cells or tissues without causing immediate visible degenerative changes.<ref>{{Cite web |title=Medical Definition of VITAL DYE |url=https://www.merriam-webster.com/medical/vital%20dye |access-date=2024-10-24 |website=www.merriam-webster.com |language=en}} </ref> Such dyes are useful in medical and pathological fields in order to selectively color certain structures (such as cells) in order to distinguish them from surrounding tissue and thus make them more visible for study (for instance, under a microscope). As the visibility is meant to allow study of the cells or tissues, it is usually important that the dye not have other effects on the structure or function of the tissue that might impair objective observation.

A distinction is drawn between dyes that are meant to be used on cells that have been removed from the organism prior to study (supravital staining) and dyes that are used within a living body - administered by injection or other means (intravital staining) - as the latter is (for instance) subject to higher safety standards, and must typically be a chemical known to avoid causing adverse effects on any biochemistry (until cleared from the tissue), not just to the tissue being studied, or in the short term.

The term "vital stain" is occasionally used interchangeably with both intravital and supravital stains, the underlying concept in either case being that the cells examined are still alive.
In a stricter sense, the term "vital staining" means the polar opposite of "supravital staining."
If living cells absorb the stain during supravital staining, they exclude it during "vital staining"; for example, they color negatively while only dead cells color positively, and thus viability can be determined by counting the percentage of total cells that stain negatively.
Because the dye determines whether the staining is supravital or intravital, a combination of supravital and vital dyes can be used to more accurately classify cells into various groups (e.g., viable, dead, dying).<ref>{{cite book | last=Ionescu | first=Sinziana | title=Current Topics in Colorectal Surgery | chapter=The Use of Indocyanine Green in Colorectal Surgery | publisher=IntechOpen | date=2023-07-26 | isbn=978-1-83962-335-6 | doi=10.5772/intechopen.100301 | doi-access=free | url=https://www.intechopen.com/citation-pdf-url/78967 }}{{CC-notice|by3}}</ref>

==See also==

{{div col}}
* [[Biological pigment]], any colored substance in organisms
* [[Blue Wool Scale]]
* [[Hair coloring]]
* [[Industrial dye degradation]]
* [[J-aggregate]]
* [[Laser dye]]s
* [[List of dyes]]
* [[Oxidant]]
* [[Phototendering]]
* [[Stain]]
* [[:Category:Natural dyes|Natural dyes]]
* [[:Category:Pigments|Pigments]]
** [[:Category:Inorganic pigments|Inorganic pigments]]
** [[:Category:Organic pigments|Organic pigments]]
{{div col end}}

==References==
{{Reflist}}

==Further reading==
{{wiktionary|leuco form}}
* Abelshauser, Werner. ''German History and Global Enterprise: BASF: The History of a Company'' (2004) covers 1865 to 2000
* Beer, John J. ''The Emergence of the German Dye Industry'' (1959)
*{{Cite web |title=Synthetic Dye - an overview {{!}} ScienceDirect Topics |url=https://www.sciencedirect.com/topics/engineering/synthetic-dye |access-date=2022-11-18 |website=www.sciencedirect.com}}

{{Dyeing}}

{{Authority control}}

[[Category:Dyes| ]]
[[Category:Textile chemistry]]