Editing Lac (resin)

{{Short description|Resinous secretion of lac insects}}
[[File:Kerria-lacca.jpg|300px|thumb|Lac tubes created by ''[[Kerria lacca]]'']]
[[Image:Shellac varities.png|right|thumb|Resin secreted by the female lac bug on trees is processed and sold as dry flakes.]]
'''Lac''' is the resinous secretion of a number of species of [[Kerriidae|lac insects]], of which the most commonly cultivated is ''[[Kerria lacca]]''.

Cultivation begins when a farmer gets a stick that contains eggs ready to hatch and ties it to the tree to be infested.<ref name=Derry2012Page27>{{cite web|last1=Derry|first1=Juliane|title=Investigating Shellac: Documenting the Process, Defining the Product|url=https://www.duo.uio.no/bitstream/handle/10852/34480/Derry-Master.pdf|publisher=Project-Based Masters Thesis, University of Oslo|access-date=3 July 2014|page=27|year=2012}}</ref> Thousands of lac insects colonize the branches of the host trees and secrete the resinous pigment. The coated branches of the host trees are cut and harvested as '''sticklac'''.

The harvested sticklac is crushed and sieved to remove impurities. The sieved material is then repeatedly washed to remove insect parts and other material. The resulting product is known as '''seedlac'''. The prefix ''seed'' refers to its pellet shape. Seedlac, which still contains 3–5% impurity, is processed into '''[[shellac]]''' by heat treatment or [[solvent extraction]].

The leading producer of lac is [[Jharkhand]], followed by the [[Chhattisgarh]], [[West Bengal]], and [[Maharashtra]] states of India.{{Citation needed|date=October 2024}} Lac production is also found in [[Bangladesh]], [[Myanmar]], [[Thailand]], [[Laos]], [[Vietnam]], parts of [[China]], and [[Mexico]].

==Etymology==
{{see also|Lacquer}}
The word ''lac'' is derived from the [[Sanskrit]] word [[Lakh#Etymology and regional variants|''lāksh''ā'' '''(लाक्षा)]]  representing the number 100 thousand, which was used for both the lac insect (because of their enormous number) and the scarlet resinous secretion it produces that was used as wood finish, lacquerware, skin cosmetic, ornaments and dye for wool and silk in ancient India and neighbouring areas.<ref name="ref38hodop">{{Citation | title=The art of dyeing in the history of mankind | author=Franco Brunello | publisher=AATCC, 1973 | isbn= | url=https://books.google.com/books?id=MI-vbcXDdssC | quote=''... The word lacquer derives, in fact, from the Sanskrit 'Laksha' and has the same meaning as the Hindi word 'Lakh' which signifies one-hundred thousand ... enormous number of those parasitical insects which infest the plants Acacia catecu, Ficus and Butea frondosa ... great quantity of reddish colored resinous substance ... used in ancient times in India and other parts of Asia very widely ...'' | year=1973}}</ref><ref name="ref08bepip">{{Citation | title=Polyurethanes: coatings, adhesives and sealants | author=Ulrich Meier-Westhues | publisher=Vincentz Network GmbH & Co KG, 2007 | isbn=978-3-87870-334-1 | url=https://books.google.com/books?id=wzOkvpgxLLQC | quote=''... Shellac, a natural resin secreted by the scaly lac insect, has been used in India for centuries as a decorative coating for surfaces. The word lacquer in English is derived from the Sanskrit word laksha. which means one hundred thousand ...'' | date=November 2007}}</ref> Lac resin was once imported in sizeable quantity into Europe from India along with Eastern woods. These were being used very widely.<ref name="ref76jezah">{{Citation | title=Asia in the making of Europe, Volume 2, Book 1 | author=Donald Frederick Lach, Edwin J. Van Kley | publisher=University of Chicago Press, 1971 | isbn=978-0-226-46730-6 | url=https://books.google.com/books?id=BOitAB1Q0QcC | quote=''... Along with valuable woods from the East, the ancients imported lac, a resinous incrustation produced on certain trees by the puncture of the lac insect. In India, lac was used as sealing wax, dye and varnish ... Sanskrit, laksha; Hindi, lakh; Persian, lak; Latin, lacca. The Western word "lacquer" is derived from this term ...'' | date=1994-02-04}}</ref><ref name="ref28gulah">{{cite book |title=European coatings handbook |first1=Thomas |last1=Brock |first2=Michael |last2=Groteklaes |first3=Peter |last3=Mischke |publisher=Vincentz Network GmbH & Co KG, 2000 |isbn=978-3-87870-559-8 |url=https://books.google.com/books?id=mAPG4Hdm5ycC |quote=''... The word "lacquer" itself stems from the term "Laksha", from the pre-Christian, sacred Indian language Sanskrit, and originally referred to shellac, a resin produced by special insects ("lac insects") from the sap of an Indian fig tree ...'' |year=2000 }}</ref>

== Host trees ==
[[File:Pongamia pinnata.jpg|thumb|upright|Pongam or honge (''[[Millettia pinnata]]'') is a native of India and grows in profusion, generally planted as avenue trees by the forest department. It is renowned for its shade and is well known in traditional uses for its medicinal properties. It is also grown as a host plant for lac insects. The tree is also one of the food plants for common cerulean (''[[Jamides celeno]]'').]]

''Kerria lacca'' can be cultivated on either cultivated or wild host plants.
* In India the most common host plants are:
** Dhak (''[[Butea monosperma]]'')
** Ber (''[[Ziziphus mauritiana]]'')
** Kusum (''[[Schleichera oleosa]]'') (reported to give the best quality and yield)<ref>Iwasa, S, 1997. Schleichera oleosa (Lour.) Oken. In Faridah Hanum, I. & van der Maesen, L.J.G. (Eds.): Plant Resources of South-East Asia No. 11. Auxiliary Plants. Prosea Foundation, Bogor, Indonesia. pp. 227-229.</ref>
* In Thailand the most common host plants are
** Rain tree (''[[Albizia saman]]'')
** Pigeon pea (''[[Cajanus cajan]]'')
* In China the common host plants include
** Pigeon pea (''[[Cajanus cajan]]'')
** [[Hibiscus]] species
* In Mexico
** Barbados nut (''[[Jatropha curcas]]'')

Estimated yields per tree in India are 6–10&nbsp;kg for [[kusum]], 1.5–6&nbsp;kg for [[Ziziphus mauritiana|ber]], and 1–4&nbsp;kg for [[Butea monosperma|dhak]].<ref name=FAO1995Ch5 /> The bugs' life cycles can produce two sticklac yields per year, though it may be better to rest for six months to let the host tree recover.<ref name=Derry2012Page28>{{cite web|last1=Derry|first1=Juliane|title=Investigating Shellac: Documenting the Process, Defining the Product|url=https://www.duo.uio.no/bitstream/handle/10852/34480/Derry-Master.pdf|publisher=Project-Based Masters Thesis, University of Oslo|access-date=3 July 2014|page=28|year=2012}}</ref>

==Harvesting==
Lac is harvested by cutting the tree branches that hold sticklac. If dye is being produced, the insects are kept in the sticklac because the dye colour comes from the insects rather than their resin. They may be killed by exposure to the sun.  On the other hand, if seedlac or shellac is being produced, most insects can escape because less coloured pale lac is generally more desired.<ref name=FAO1995Ch5 />{{clarify|date=July 2022}}

== Uses ==
[[File:Laksha - ලාක්ෂා - Lacquerware.jpg|thumb|right|''"Laksha"'' is a traditional form of lacquerware from Sri Lanka which is made from shellac derived from Lac.]]
The use of lac [[dye]] goes back to ancient times. It was used in ancient India and neighbouring areas as wood finish, skin cosmetic, lacquerware and dye for wool and silk.<ref name="ref38hodop" /><ref name="ref08bepip"/><ref name=FAO1995Ch5>{{cite book|last1=Green|first1=C. L.|title=Non-Wood Forest Products 4: Natural colourants and dyestuffs|date=1995|publisher=Food and Agriculture Organization of the United Nations|location=Rome|url=http://www.fao.org/docrep/v8879e/v8879e08.htm|access-date=3 July 2014|chapter=5: Insect Dyes|archive-date=12 August 2011|archive-url=https://web.archive.org/web/20110812090550/http://www.fao.org//docrep/V8879E/V8879e08.htm|url-status=dead}}</ref> In China, it is a traditional dye for leather goods. Lac for dye has been somewhat replaced by the emergence of synthetic dyes,<ref name=FAO1995Ch5 /> though it remains in use, and some juices, carbonated drinks, wine, jam, sauce, and candy are coloured using it.<ref name=Flinn2011>{{cite web|last=Flinn|first=Angel|title=Shellac & Food Glaze|url=http://gentleworld.org/shellac-food-glaze/|website=Gentle World|access-date=3 July 2014|date=15 Aug 2011}}</ref> It is still used as [[sealing wax]] by the [[India Post]]<ref name=indiapost1>[https://www.itokri.com/pages/the-art-of-sealing "The art of sealing."]</ref> but its use is being phased out.<ref>{{Cite web |last=Admin |title=Department of Post (DOP) Special Campaign 2.0 {{!}} Post Office (DOP) Decided to Discontinue the use of sealing wax and replace with recyclable seals |url=https://www.postalstudy.in/2022/10/department-of-post-dop-special-campaign.html |access-date=2023-08-23 |language=en }}</ref>

Lac is used in [[folk medicine]] as a [[hepatoprotective]] and [[anti-obesity medication|anti-obesity drug]]. <ref>{{Cite web|url=https://med.stanford.edu/news/all-news/2024/03/metformin-weight-diabetes.html#:~:text=The%20finding%2C%20made%20jointly%20by%20researchers%20at,a%20new%20class%20of%20weight%20loss%20drugs.|title=Weight loss caused by common diabetes drug tied to "anti-hunger" molecule in study|access-date=2025-02-04|website=Standford medicine}}</ref> It is used in [[violin]] and other [[varnish]] and is soluble in [[ethanol|alcohol]]. This type of lac was used in the finishing of 18th-century fowling guns in the United States.{{Citation needed|date=January 2021}}

== Production levels ==
[[File:Shellac three colours.jpeg|thumb|Processed shellac flakes from lac insect resin.]]
India exported significant amounts of sticklac derivatives, especially lac dye, from the 1700s to the late 1800s. Production declined as synthetic dyes emerged, and after the late 1940s, production of seedlac and shellac also declined due to replacement.<ref name=FAO1995Ch5 />

In the mid-1950s, India annually produced about 50,000 tons of sticklac and exported about 29,000 tons of lac; by the late 1980s the figures were about 12,000 tons and 7,000 tons, respectively. By 1992–93, India's lac exports fell further to 4,500 tons. In the same period, Thailand's production increased somewhat, with annual lac exports of around 7,000 tons in the 1990s, mainly of seedlac. China exported only about 500 tons of shellac per year in the 1990s but produced more lac internally: 4,000-5,000 tons of sticklac and 2,000–3,000 tons of shellac in [[Yunnan]] province, with additional, smaller production in [[Fujian]] province. While India, Thailand, and China are the major lac producers, Bangladesh, Myanmar, Vietnam, and Sri Lanka also play small roles.<ref name=FAO1995Ch5 />

== Description in ancient texts ==
Usage of ''lac''/''lah''/''laksha'' is described in ancient Hindu literature [[Atharvaveda]] also. Kand 5 and Sukta 5 (chapter 5, verse 5) is called as Laksha Sukti - verse related to lac. This entire verse is dedicated to lac and its usage. It has description of many ancient practices.

[[Mahabharata|The Mahabharata]] mentions the [[Lakshagriha]], which was built by the [[Kaurava]]s to house the [[Pandava]]s. The intention of Kauravan was to burn the Pandavas by setting fire to the Lakshagriha.{{Citation needed|date=January 2021}}

==Species==
*''[[Kerria lacca]]'' – the true lac scale
*''[[Paratachardina decorella]]'' – the rosette lac scale
*''[[Paratachardina pseudolobata]]'' – the lobate lac scale
*''[[Kerria javana]]''

== See also ==
* [[Carmine]] (E120) – Another pigment extracted from an insect.
* [[Lacquer]] – A product that was at one time made from lac, but in modern common usage now refers to a separate product with similar properties.
* [[Lake pigment]]
* [[Shellac]] – A protective coating made from lac.

==References==
<references/>

==External links==
{{EB1911 Poster|Lac}}
*{{Commons category-inline}}
*[https://web.archive.org/web/20180929175743/http://ilri.ernet.in/ Indian Institute of Natural Resins and Gums - IINRG, formerly Indian Lac Research Institute - ILRI]
*[http://www.fao.org/docrep/v8879e/v8879e08.htm FAO - Insect dyes - Lac - Summary of Basic Information] {{Webarchive|url=https://web.archive.org/web/20110812090550/http://www.fao.org//docrep/V8879E/V8879e08.htm |date=2011-08-12 }}

{{Insects in culture}}

[[Category:Insect products]]
[[Category:Animal dyes]]
[[Category:Resins]]
[[Category:Kerriidae]]