Lacquer

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For items made with lacquer, see Lacquerware. Lacquer_sentence_0

The term lacquer is used for a number of hard and potentially shiny finishes applied to materials such as wood or metal. Lacquer_sentence_1

These fall into a number of very different groups. Lacquer_sentence_2

The term lacquer originates from the Sanskrit word lākshā (लाक्षा) representing the number 100,000, which was used for both the lac insect (because of their enormous number) and the scarlet resinous secretion, rich in shellac, that it produces that was used as wood finish in ancient India and neighbouring areas. Lacquer_sentence_3

Asian lacquerware, which may be called "true lacquer", are objects coated with the treated, dyed and dried sap of Toxicodendron vernicifluum or related trees, applied in several coats to a base that is usually wood. Lacquer_sentence_4

This dries to a very hard and smooth surface layer which is durable, waterproof, and attractive in feel and look. Lacquer_sentence_5

Asian lacquer is sometimes painted with pictures, inlaid with shell and other materials, or carved, as well as dusted with gold and given other further decorative treatments. Lacquer_sentence_6

In modern techniques, lacquer means a range of clear or pigmented coatings that dry by solvent evaporation to produce a hard, durable finish. Lacquer_sentence_7

The finish can be of any sheen level from ultra to high gloss, and it can be further polished as required. Lacquer_sentence_8

Lacquer finishes are usually harder and more brittle than oil-based or latex paints, and are typically used on hard and smooth surfaces. Lacquer_sentence_9

In terms of modern finishing products, lac-based finishes are likely to be referred to as shellac, while lacquer refers to synthetic polymers such as nitrocellulose, cellulose acetate butyrate ("CAB"), or acrylic resin dissolved in lacquer thinner, a mixture of solvents such as ketones (acetone, MEK), esters (butyl acetate, methoxypropyl acetate), aromatic hydrocarbons (toluene, xylene), ethers (cellosolve), and alcohols. Lacquer_sentence_10

Synthetic lacquer is more durable than shellac. Lacquer_sentence_11

Etymology Lacquer_section_0

The English lacquer is from the archaic French word lacre "a kind of sealing wax", from Portuguese lacre, itself an unexplained variant of Medieval Latin lacca "resinous substance" from Arabic lakk, from Persian lak, from Hindi lakh (Prakrit lakkha). Lacquer_sentence_12

These ultimately derive from Sanskrit lākshā (लाक्षा), which was used for both the Lac insect and the scarlet resinous secretion it produces that was used as wood finish. Lacquer_sentence_13

Lac resin was once imported in sizeable quantity into Europe from India along with Eastern woods. Lacquer_sentence_14

Sheen measurement Lacquer_section_1

Lacquer sheen is a measurement of the shine for a given lacquer. Lacquer_sentence_15

Different manufacturers have their own names and standards for their sheen. Lacquer_sentence_16

The most common names from least shiny to most shiny are: flat, matte, egg shell, satin, semi-gloss, and gloss (high). Lacquer_sentence_17

Shellac-based lacquers Lacquer_section_2

Urushiol-based lacquers Lacquer_section_3

Main article: Urushiol Lacquer_sentence_18

Urushiol-based lacquers differ from most others, being slow-drying, and set by oxidation and polymerization, rather than by evaporation alone. Lacquer_sentence_19

In order for it to set properly it requires a humid and warm environment. Lacquer_sentence_20

The phenols oxidize and polymerize under the action of an enzyme laccase, yielding a substrate that, upon proper evaporation of its water content, is hard. Lacquer_sentence_21

These lacquers produce very hard, durable finishes that are both beautiful and very resistant to damage by water, acid, alkali or abrasion. Lacquer_sentence_22

The active ingredient of the resin is urushiol, a mixture of various phenols suspended in water, plus a few proteins. Lacquer_sentence_23

The resin is derived from trees indigenous to East Asia, like lacquer tree Toxicodendron vernicifluum, and wax tree Toxicodendron succedaneum. Lacquer_sentence_24

The fresh resin from the T. vernicifluum trees causes urushiol-induced contact dermatitis and great care is required in its use. Lacquer_sentence_25

The Chinese treated the allergic reaction with crushed shellfish, which supposedly prevents lacquer from drying properly. Lacquer_sentence_26

Lacquer skills became very highly developed in Asia, and many highly decorated pieces were produced. Lacquer_sentence_27

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, although various prehistoric lacquerwares have been unearthed in China dating back to the Neolithic period and objects with lacquer coating in Japan from the late Jōmon period. Lacquer_sentence_28

The earliest extant lacquer object, a red wooden bowl, was unearthed at a Hemudu culture (5000–4500 BC) site in China. Lacquer_sentence_29

By the Han Dynasty (206 BC – 220 AD), many centres of lacquer production became firmly established. Lacquer_sentence_30

The knowledge of the Chinese methods of the lacquer process spread from China during the Han, Tang and Song dynasties. Lacquer_sentence_31

Eventually it was introduced to Korea, Japan, Southeast and South Asia. Lacquer_sentence_32

Trade of lacquer objects travelled through various routes to the Middle East. Lacquer_sentence_33

Known applications of lacquer in China included coffins, music instruments, furniture, and various household items. Lacquer_sentence_34

Lacquer mixed with powdered cinnabar is used to produce the traditional red lacquerware from China. Lacquer_sentence_35

From the 16th century to the 17th century, lacquer was introduced to Europe on a large scale for the first time through trade with Japanese. Lacquer_sentence_36

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 The Society of Jesus collected Japanese lacquerware luxuriously decorated with maki-e. Lacquer_sentence_37

The terms related to lacquer such as "Japanning", "Urushiol" and "maque" which means lacquer in Mexican Spanish, are derived from Japanese. Lacquer_sentence_38

The trees must be at least ten years old before cutting to bleed the resin. Lacquer_sentence_39

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_sentence_40

Lacquer-yielding trees in Thailand, Vietnam, Burma and Taiwan, called Thitsi, are slightly different; they do not contain urushiol, but similar substances called "laccol" or "thitsiol". Lacquer_sentence_41

The end result is similar but softer than the Chinese or Japanese lacquer. Lacquer_sentence_42

Burmese lacquer sets slower, and is painted by craftsmen's hands without using brushes. Lacquer_sentence_43

Raw lacquer can be "coloured" by the addition of small amounts of iron oxides, giving red or black depending on the oxide. Lacquer_sentence_44

There is some evidence that its use is even older than 8,000 years from archaeological digs in China. Lacquer_sentence_45

Later, pigments were added to make colours. Lacquer_sentence_46

It is used not only as a finish, but 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. Lacquer_sentence_47

The process is called "kanshitsu" in Japan. Lacquer_sentence_48

Advanced decorative techniques using additional materials such as gold and silver powders and flakes ("makie") were refined to very high standards in Japan also after having been introduced from China. Lacquer_sentence_49

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. Lacquer_sentence_50

There are a number of forms of urushiol. Lacquer_sentence_51

They vary by the length of the R chain, which depends on the species of plant producing the urushiol. Lacquer_sentence_52

Urushiol can also vary in the degree of saturation in the carbon chain. Lacquer_sentence_53

Urushiol can be drawn as follows: , where: Lacquer_sentence_54

R = (CH2)14CH3 or R = (CH2)7CH=CH(CH2)5CH3 or R = (CH2)7CH=CHCH2CH=CH(CH2)2CH3 or R = (CH2)7CH=CHCH2CH=CHCH=CHCH3 or R = (CH2)7CH=CHCH2CH=CHCH2CH=CH2 Lacquer_sentence_55


Credits to the contents of this page go to the authors of the corresponding Wikipedia page: en.wikipedia.org/wiki/Lacquer.