Editing Lacquer (section)

==Urushiol-based lacquers==
[[File:Red lacquer tray, Song Dynasty.jpg|thumb|A Chinese six-pointed tray, red lacquer over wood, from the Song dynasty (960–1279), 12th–13th century, Metropolitan Museum of Art.]]
[[Urushiol]]-based lacquers differ from most others, being slow-drying, and set by [[oxidation]] and [[polymerization]], rather than by [[evaporation]] alone. The active ingredient of the resin is urushiol, a mixture of various phenols suspended in water, plus a few proteins. In order for it to set properly it requires a humid and warm environment. The phenols oxidize and polymerize under the action of [[laccase]] enzymes, yielding a substrate that, upon proper evaporation of its water content, is hard. These lacquers produce very hard, durable finishes that are both beautiful and very resistant to damage by water, acid, alkali or abrasion. The resin is derived from trees indigenous to East Asia, like lacquer tree ''[[Toxicodendron vernicifluum]]'', and wax tree ''[[Toxicodendron succedaneum]]''.<ref>{{cite web|url=https://www.britannica.com/eb/article-9057370/Oriental-lacquer|title=Oriental lacquer – varnish resin|website=Britannica.com|access-date=27 October 2017}}</ref> The fresh resin from the ''T. vernicifluum'' trees causes [[urushiol-induced contact dermatitis]] and great care is therefore required in its use. The Chinese treated the allergic reaction with crushed shellfish, which supposedly prevents lacquer from drying properly.<ref>Major, John S., Sarah Queen, Andrew Meyer, Harold D. Roth, (2010), ''The Huainanzi: A Guide to the Theory and Practice of Government in Early Han China'', Columbia University Press, p. 219.</ref> Lacquer skills became very highly developed in Asia, and many highly decorated pieces were produced.

It has been confirmed that the lacquer tree has existed in Japan since nearly 12,600 years ago in the incipient [[Jōmon period]]. This was confirmed by [[radioactive carbon dating]] of the lacquer tree found at the [[Torihama shell mound]] and is the oldest lacquer tree in the world found as of 2011.<ref name = "nikkei1106">[https://megalodon.jp/2020-0707-0601-06/https://www.nikkei.com:443/article/DGXNASDG06018_W1A101C1CC1000/ 1万2千年前のウルシ木片 世界最古、福井で出土], [[The Nikkei]], November 6, 2011</ref> Lacquer was used in Japan as early as 7000 BCE, during the Jōmon period. Evidence for the earliest lacquerware was discovered at the Kakinoshima "B" Excavation Site in [[Hokkaido]]. The ornaments woven with lacquered red thread were discovered in a pit grave dating from the first half of the Initial Jōmon period. Also, at Kakinoshima "A" Excavation Site, earthenware with a spout painted with vermilion lacquer, which was made 3200 years ago, was found almost completely intact.<ref name = "kakinoshima">{{cite web|url=https://en.visit-hokkaido.jp/what-to-do/kakinoshima-jomon-archaeological-site/|archive-url=https://web.archive.org/web/20200707075655/https://en.visit-hokkaido.jp:443/what-to-do/kakinoshima-jomon-archaeological-site/|title=Kakinoshima Jomon Archaeological Site|publisher=Hokkaido Prefectural Government, Hokkaido Tourism Organization|archive-date=7 July 2020|access-date=13 November 2022}}</ref><ref>[https://web.archive.org/web/20200128174441/http://www.pref.hokkaido.lg.jp/ks/bns/jomon/remains_is_kakinoshima01.htm Kakinoshima Excavation Site] Hokkaido Government</ref><ref name = "nikkei1106"/>

During the [[Shang dynasty]] (1600–1046 BC), the sophisticated techniques used in the lacquer process were first developed and it became a highly artistic craft,<ref name=webb/> although various prehistoric [[lacquerware]]s have been unearthed in China dating back to the [[Neolithic]] period.<ref name=webb/> The earliest extant Chinese lacquer object, a red wooden bowl,<ref>Stark, Miriam T. (2005). ''Archaeology of Asia''. Malden, MA : Blackwell Pub. p.&nbsp;30. {{ISBN|1-4051-0213-6}}.</ref> was unearthed at a [[Hemudu culture]] (5000–4500 BC) site in China.<ref>Wang, Zhongshu. (1982). ''Han Civilization''. Translated by K.C. Chang and Collaborators. New Haven and London: Yale University Press. p.&nbsp;80. {{ISBN|0-300-02723-0}}.</ref> By the [[Han dynasty]] (206 BC – 220 AD), many centres of lacquer production became firmly established.<ref name=webb>{{cite book|last=Webb|first=Marianne|title=Lacquer: Technology and conservation|year=2000|publisher=Butterworth-Heinemann|location=Oxford|isbn=978-0-7506-4412-9|page=3}}</ref> The knowledge of the Chinese methods of the lacquer process spread from China during the [[Han dynasty|Han]], [[Tang dynasty|Tang]] and [[Song dynasty|Song]] dynasties. Eventually it was introduced to Korea and Japan.<ref>{{cite book|title=Ancient China's technology and science|year=1983|publisher=Foreign Languages Press|location=Beijing|isbn=978-0-8351-1001-3|page=211|editor=Institute of the History of Natural Sciences and Chinese Academy of Sciences}}</ref>

Trade of lacquer objects travelled through various routes to the Middle East. Known applications of lacquer in China included coffins, music instruments, furniture, and various household items.<ref name=webb/> Lacquer mixed with powdered [[cinnabar]] is used to produce the traditional red lacquerware from China.

[[File:花鳥蒔絵螺鈿書箪笥-Cabinet of Drawers with Birds and Flowers MET DT6048.jpg|thumb|right|A [[maki-e]] and mother-of-pearl inlay cabinet that was exported from Japan to Europe in the 16th century.]]
From the 16th century to the 17th century, lacquer was introduced to Europe on a large scale for the first time through [[Nanban trade|trade with Japanese]]. Until the 19th century, lacquerware was one of Japan's major exports, and European royalty, aristocrats and religious people represented by [[Marie-Antoinette]], [[Maria Theresa]] and [[Society of Jesus|The Society of Jesus]] collected [[Japanese lacquerware]] luxuriously decorated with [[maki-e]].<ref>[https://web.archive.org/web/20191225065626/http://en.urushi-joboji.com/urushi Urushi once attracted the world] urushi-joboji.com</ref><ref name = "murata24">Masayuki Murata. ''明治工芸入門'' p.24. Me no Me, 2017 {{ISBN|978-4907211110}}</ref> The terms related to lacquer such as "[[Japanning]]", "Urushiol" and "''maque''" which means lacquer in Mexican Spanish, are derived from Japanese.<ref name=tedjj>{{cite web  |author= Ted J.J. Leyenaar  |title= Mexican lacquers from Guerrero /La laca Mexicana de Guerrero  |publisher= National Museum of Ethnology Museum Volkenkunde  |location= Netherlands  |url= http://volkenkunde.nl/sites/default/files/attachements/lacquers.pdf  |access-date= June 10, 2015  |url-status= dead|archive-url= https://web.archive.org/web/20141213084655/http://volkenkunde.nl/sites/default/files/attachements/lacquers.pdf  |archive-date= December 13, 2014  }}</ref><ref name=lacmaorg>{{cite web |author= Kathryn Santner |title= Writ in Lacquer: A Genteel Courtship on a Mexican Sewing Box |publisher= Los Angeles County Museum of Art |location=Los Angeles |date= October 2, 2012|url= http://unframed.lacma.org/2012/10/02/writ-in-lacquer-a-genteel-courtship-on-a-mexican-sewing-box |access-date=June 10, 2015}}</ref>

The trees must be at least ten years old before cutting to bleed the resin. It sets by a process called "aqua-polymerization", absorbing oxygen to set; placing in a humid environment allows it to absorb more oxygen from the evaporation of the water.

Lacquer-yielding trees in [[Thailand]], [[Vietnam]], [[Myanmar|Burma]] and [[Taiwan]], called [[Melanorrhoea usitata|Thitsi]], are slightly different; they do not contain urushiol, but similar substances called laccol or thitsiol. The result is similar but softer than the Chinese or Japanese lacquer. Burmese lacquer sets slower, and is painted by craftsmen's hands without using brushes.

Raw lacquer can be "coloured" by the addition of small amounts of [[iron oxide]]s, giving red or black depending on the oxide. There is some evidence that its use is even older than 8,000 years from archaeological digs in Japan and China. Later, pigments were added to make colours. It is used not only as a finish, because if mixed with ground fired and unfired clays applied to a mould with layers of hemp cloth, it can produce objects without need for another core like wood. The process is called "kanshitsu" in Japan. In the lacquering of the Chinese musical instrument, the [[guqin]], the lacquer is mixed with deer horn powder (or ceramic powder) to give it more strength so it can stand up to the fingering.

There are a number of forms of urushiol. They vary by the length of the R chain, which depends on the species of plant producing the urushiol. Urushiol can also vary in the degree of saturation in the carbon chain. Urushiol can be drawn as follows:
[[File:Urushiol.png|100px]], where:

R = (CH<sub>2</sub>)<sub>14</sub>CH<sub>3</sub> or<br />R = (CH<sub>2</sub>)<sub>7</sub>CH=CH(CH<sub>2</sub>)<sub>5</sub>CH<sub>3</sub> or<br />R = (CH<sub>2</sub>)<sub>7</sub>CH=CHCH<sub>2</sub>CH=CH(CH<sub>2</sub>)<sub>2</sub>CH<sub>3</sub> or<br />R = (CH<sub>2</sub>)<sub>7</sub>CH=CHCH<sub>2</sub>CH=CHCH=CHCH<sub>3</sub> or<br />R = (CH<sub>2</sub>)<sub>7</sub>CH=CHCH<sub>2</sub>CH=CHCH<sub>2</sub>CH=CH<sub>2</sub>

=== Gallery ===
<gallery>
File:Armorial screen.jpg|Armorial screen
File:Oval Tray (Duoyuan Pan) with Pavilion on a Garden Terrace LACMA M.81.125.1.jpg|A Chinese [[carved lacquer]] oval tray, [[Yuan dynasty]], {{Circa|13th century}}.
File:Freer 002.jpg|[[Ming dynasty]] Chinese [[lacquerware]] container, dated 16th century.
File:나전 칠 모란 넝쿨 무늬 옷상자-조선-螺鈿漆牡丹唐草文衣箱子 朝鮮-Clothing box decorated with peony scrolls MET DP704158.jpg|Clothing box decorated with peony scrolls, [[Joseon dynasty]] Korea, 17th century.
File:壽字吉祥文蒔絵印籠 - Inrō with the Characters for Longevity and Good Fortune and the “Seven Lucky Treasures” on Checkerboard Ground.jpg|{{lang|ja-Latn|[[Inro]]}} in [[maki-e]] Lacquer, [[Edo period]] Japan, 18th century
File:竹貼源氏蒔絵提重-Picnic Box with Design of the Scene from the Tale of Genji in Maki-e Lacquer.jpg|Picnic Box with Design of the Scene from ''[[The Tale of Genji]]'' in Maki-e Lacquer, Edo or [[Meiji period]] Japan, 19th century
</gallery>

===Types of lacquer===
[[File:Lacquer in liquid form, mixed with water and turpentine.jpg|thumb|Lacquer mixed with water and [[turpentine]], ready for applying to surface.]]
Types of lacquer vary from place to place but they can be divided into unprocessed and processed categories.

The basic unprocessed lacquer is called ''raw lacquer'' (生漆: ''ki-urushi'' in Japanese, ''shengqi'' in Chinese). This is directly from the tree itself with some impurities filtered out. Raw lacquer has a water content of around 25% and appears in a light brown colour. This comes in a standard grade made from Chinese lacquer, which is generally used for ground layers by mixing with a powder, and a high-quality grade made from Japanese lacquer called ''kijomi-urushi'' (生正味漆) which is used for the last finishing layers.

The processed form (in which the lacquer is stirred continuously until much of the water content has evaporated) is called ''guangqi'' (光漆) in Chinese but comes under many different Japanese names depending on the variation, for example, ''kijiro-urushi'' (木地呂漆) is standard transparent lacquer sometimes used with pigments and ''kuroroiro-urushi'' (黒呂色漆) is the same but pre-mixed with iron hydroxide to produce a black coloured lacquer. ''Nashiji-urushi'' (梨子地漆) is the transparent lacquer but mixed with [[gamboge]] to create a yellow-tinged lacquer and is especially used for the sprinkled-gold technique. These lacquers are generally used for the middle layers. Japanese lacquers of this type are generally used for the top layers and are prefixed by the word ''jo-'' (上) which means 'top (layer)'.

Processed lacquers can have oil added to them to make them glossy, for example, ''shuai-urushi'' (朱合漆) is mixed with linseed oil. Other specialist lacquers include ''ikkake-urushi'' (釦漆) which is thick and used mainly for applying gold or silver leaf.