View source for Wax

{{Other uses}}
<div class="references-small"></div>[[Image:Montana 10 bg 061905.jpg|thumb|Wax candle]]
'''Wax''' refer to a class of [[hydrocarbon]]s that are [[Plasticity (physics)|plastic]] ([[malleability|malleable]]) at normal ambient temperatures.  Characteristically, they [[Melting point|melt]] above 45 °C (113 °F) to give a low [[viscosity]] liquid. Waxes are [[Solubility|insoluble]] in water but soluble in petroleum based solvent.
Waxes are secreted by many plants or animals, such as [[beeswax]] and [[carnauba]] (a plant [[epicuticular wax]]).  Most industrial waxes are components of fossil fuels or are synthesized from petroleum-derived compounds, such as [[paraffin]]. ''[[Earwax]]'' is an oily substance found in the human [[ear]]. Many materials such as [[silicone]] wax exhibit similar properties, and are also described as wax or waxy. [[Image:Beeswax foundation.jpg|thumb|Commercial [[honeycomb]] foundation, made by pressing beeswax between patterned metal rollers.]]

==Classification of waxes==
A wax is a type of [[hydrocarbon]] that typically contains long-chain [[alkanes]] often containing ester, carboxylic acid, or alcohol [[functional group|groups]].  The structure and molecular weight of the hydrocarbon chain and the relative concentration of the functional groups determine the hardness of the wax. Natural waxes especially are mixtures of several kinds of waxes whereas petroleum-derived waxes tend to be more homogeneous.  Waxes can be classified according to their sources.
===Natural waxes===
====Plant waxes====
Especially in warm climates, plants secrete waxes as a way to control evaporation and hydration.<ref name=Ullmann/> The most important is [[Carnauba wax]], a hard wax with many applications.  Other more specialized vegetable waxes include [[candelilla wax]], ouricury wax, sugarcane wax, retamo wax, [[jojoba oil]]. The [[epicuticular wax]]es of plants are mixtures of substituted long-chain [[aliphatic]] [[hydrocarbon]]s, containing [[alkane]]s, fatty acids, primary and [[secondary alcohol]]s, [[diol]]s, [[ketone]]s, [[aldehyde]]s.<ref name=Baker>EA Baker (1982) Chemistry and morphology of plant epicuticular waxes. In The Plant Cuticle. Ed. DF Cutler, KL Alvin, CE Price. Academic Press. ISBN 0 12 199920 3</ref>

====Animal waxes====
The best known animal wax is beeswax but other insects secrete waxes and wool contains much wax.  Beeswax is a substance secreted by [[bee]]s and used in constructing their [[honeycomb]]s.  With a melting point 62 -65 °C, beeswax is primarily composed of esters with only a few percent of paraffin waxes.
===Petroleum derived waxes===
Paraffin waxes are [[hydrocarbon]]s, mixtures of [[alkanes]] usually in a [[homologous series]] of chain lengths.  These materials represent a significant fraction of petroleum.  They are refined by vacuum distillation.  Paraffin waxes are mixtures of saturated of n- and isoalkanes, naphthenes, and alkyl- and naphthene-substituted aromatic compounds. The degree of branching has an important influence on the properties.  Million tons of paraffin waxes are produced annually. They are used as adhesives, in foods (chewing gum cheese wrapping), cosmetic, as coatings.

====Montan wax====
[[Montan wax]] is a fossilized wax extracted from coal and [[lignite]].  It is very hard, reflecting the high concentration of saturated [[fatty acid]]s and alcohols, not esters that characterize softer waxes.  Although dark brown and smelly, they can be purified and bleached to give commercially useful products.

====Polyethylene and related derivatives====
{{Copyedit|date=September 2010}}
Waxes are obtained by cracking polyethylene by heating for a few minutes at 400 °C.  The products have formulas of about (CH<sub>2</sub>)<sub>n</sub>H<sub>2</sub>, where n is about 50 or 100.  As of 1995, about 200 million kilograms/y were consumed.{{Citation needed|date=September 2010}}

== Uses of wax ==
Waxes are mainly consumed industrially as components of complex formulations, often for coatings.<ref name=Ullmann>Uwe Wolfmeier,Hans Schmidt, Franz-Leo Heinrichs, Georg Michalczyk, Wolfgang Payer,Wolfram Dietsche, Klaus Boehlke, Gerd Hohner, Josef Wildgruber "Waxes" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2002. {{DOI|10.1002/14356007.a28_103}}.</ref> The main use of polyethylene and polypropylene waxes is in the formulation of colourants for plastics.  Waxes confer matting effects and wear resistence to paints. Polyethyelene waxes are incorporated into inks in the form of dispersions to decrease friction.  They are employed as [[release agent]]s.  They are also used as slip agents, e.g. in furniture, and corrosion resistence.

===Candles===
Waxes and hard fats such as [[tallow]] have long been use to make [[candle]]s, used for lighting and decoration in a number of religious traditions, including Christianity and Hinduism, as well as various neo-pagan religions such as Wicca. The Emperor Constantine is reported to have called for the use of candles during an Easter service in the 4th century AD.  Candles continue to be used today by Christians<ref>The Hive and the Honey Bee, ed. Dadant & sons, revised 1975, p. 540</ref> in worship as symbols of the light of Christ. In the Roman Catholic Church, beeswax candles are used, since a colony of bees is a celibate sisterhood with a single mother.<ref name=CGButler1954>Butler, C.G. (1954) ''The world of the honeybee.'' Collins, [[New Naturalist]] series, No. 29</ref> Candles of wax or tallow took the place of lamps used in various Jewish rituals such as the Sabbath lights; in the Havdalah ceremony; and the Hanukkah lights. A synagogue had to be well lit, and pious folk used to donate candles for the purpose. On the basis of the verse: 'The soul of man is a candle of the Lord' a special candle which burns twenty-four hours is kindled on the anniversary of the death of a near relative (Yahrzeit) and often two lighted candles are placed at the head of the corpse awaiting burial.<ref>Jacobs, Louis (1995) "The Jewish Religion - a Companion" Oxford University Press</ref>. Candles have also played a role in [[Paganism|pagan]] religions and in modern humanist festivals. Virtually all rituals in [[Wicca]] include the lighting of altar candles, where two main candles are often used to represent the God and the Goddess; and the lighting of candles is a central theme at the Wiccan holiday of Brigid or Imbolc, which is also known as Candlemas or the Feast of the Waxing Light. Wax candles were also used in [[secularity|secular]] life for lighting, signals in warfare, safety in travel and for time keeping, and are still in popular use today to provide soft lighting for meals and other social activities.

===Other uses===
[[File:CeciliaCheung MadameTussauds.jpg|thumb|right|200px|A typical modern [[wax sculpture]] of [[Cecilia Cheung]] at [[Madame Tussauds Hong Kong]].]]
[[Image:Velikonoční vajíčka malovaná voskem.jpg|thumb|200px|Wax-decorated [[Easter egg]]s as made in [[Ukraine]] and the [[Czech Republic]]]]
Waxes are used to make [[wax paper]], impregnating and [[coated paper|coating paper]] and card to waterproof it or make it resistant to staining, or to modify its surface properties. Waxes are also used in [[shoe polish]]es, [[wood polish]]es, and automotive polishes, as [[mold release agent]]s in [[mold making]], as a coating for many [[cheese]]s, and to [[waterproof]] leather and fabric. Wax has been used since antiquity as a temporary, removable model in [[lost-wax casting]] of [[gold]], [[silver]] and other materials.

Wax with colorful pigments added has been used as a medium in [[encaustic painting]], and is used today in the manufacture of [[crayon]]s and colored [[pencil]]s. [[Carbon paper]], used for making duplicate [[typewriter|typewritten]] documents was coated with [[carbon black]] suspended in wax, typically [[montan wax]], but has largely been superseded by [[photocopier]]s and [[computer printer]]s. In another context, [[lipstick]] and [[mascara]] are blends of various fats and waxes colored with pigments, and both [[beeswax]] and [[lanolin]] are used in other [[cosmetics]]. Also, the sports of surfing, [[skiing]], [[snowboarding]] and [[skateboarding]] often use wax to enhance the performance.  Beeswax or coloured synthetic wax is used to decorate [[Easter egg]]s in [[Ukraine]] and the [[Czech Republic]].  Paraffin wax is used in making chocolate covered bon-bons. Wax is also used in [[wax bullets]], which are used as simulation aids.

== Wax types ==
=== Animal waxes ===
* [[Beeswax]] - produced by [[honey bee]]s
* [[Chinese wax]] - produced by the [[scale insect]] ''Ceroplastes ceriferus''
* [[Earwax]] - found in the [[human]] ear.
* [[Lanolin]] (wool wax) - from the [[sebaceous glands]] of [[sheep]]
* [[Shellac]] wax - from the [[lac insect]] ''Kerria lacca''
* [[Spermaceti]] - from the head cavities and blubber of the [[sperm whale]]

=== Vegetable waxes ===<!-- This section is linked from [[Saccharomyces cerevisiae]] -->

* [[Bayberry wax]] - from the [[epicuticular wax|surface wax]] of the [[drupe|fruits]] of the bayberry shrub, ''[[Myrica faya]]''
* [[Candelilla wax]] - from the Mexican shrubs ''[[Euphorbia cerifera]]'' and ''[[Euphorbia antisyphilitica]]''
* [[Carnauba wax]] - from the leaves of the Carnauba palm, ''[[Copernica cerifera]]''
* [[Castor wax]] - catalytically hydrogenated [[castor oil]]
* [[Esparto wax]] - a byproduct of making paper from [[esparto grass]], (''Macrochloa tenacissima'')
* [[Japan wax]] - a vegetable [[triglyceride]] (not a true wax), from the berries of ''Rhus'' and ''Toxicodendron'' species
* [[Jojoba oil]] - a replacement for [[spermaceti]], jojoba is pressed from the seeds of the [[jojoba]] bush, ''Simmondsia chinensis''
* [[Ouricury wax]] - from the Brazilian feather palm, ''[[Syagrus coronata]]''.
* [[Rice bran wax]] - obtained from [[rice]] [[bran]] (''Oryza sativa'')
* [[Soy wax]] - from soybean oil

=== Mineral waxes ===
* [[Ceresin wax]]es
* [[Montan wax]] - extracted from [[lignite]] and [[brown coal]]
* [[Ozocerite]] - found in lignite beds
* [[Peat wax]]es

=== Petroleum waxes ===
* [[Paraffin wax]] - made of long-chain [[alkane]] [[hydrocarbon]]s
* [[Microcrystalline wax]] - with very fine crystalline structure
* [[Petroleum jelly]]

=== Synthetic waxes ===
* [[Polyethylene wax]]es - based on [[polyethylene]]
* [[Fischer-Tropsch wax]]es
* [[Chemically modified wax]]es - usually [[esterification|esterified]] or [[saponification|saponified]]
* [[substituted amide wax]]es
* [[polymerized α-olefins]]

== See also ==
*[[Slip melting point]]

== References ==
{{Reflist}}

== External links ==
* [http://www.cyberlipid.org/wax/wax0001.htm Waxes]
* [http://www.microcrystallinewax.net www.microcrystallinewax.net, resource for microcrystalline wax research]

{{E number infobox 900-909}}

[[Category:Waxes|Waxes]]

[[ar:شمع]]
[[ast:Cera]]
[[bs:Vosak]]
[[bg:Восък]]
[[ca:Cera]]
[[cv:Ăвăс (çилĕм)]]
[[cs:Vosk]]
[[da:Voks]]
[[de:Wachs]]
[[et:Vahad]]
[[es:Cera]]
[[eo:Vakso]]
[[fa:موم]]
[[fr:Cire]]
[[ga:Céir]]
[[gl:Cera]]
[[gu:મીણ]]
[[ko:왁스]]
[[hi:मोम]]
[[hr:Vosak]]
[[io:Vaxo]]
[[id:Malam (zat)]]
[[is:Vax]]
[[it:Cera]]
[[he:שעווה]]
[[ht:Lasi]]
[[lt:Vaškas]]
[[hu:Viasz]]
[[nl:Was (substantie)]]
[[ja:蝋]]
[[no:Voks]]
[[nn:Voks]]
[[pl:Woski]]
[[pt:Cera]]
[[ro:Ceară]]
[[qu:Mapa]]
[[ru:Воск]]
[[scn:Cira]]
[[simple:Wax]]
[[sk:Vosk]]
[[sr:Восак]]
[[fi:Vaha]]
[[sv:Vax]]
[[tl:Pagkit]]
[[ta:மெழுகு]]
[[uk:Віск]]
[[ur:موم]]
[[zh:蜡]]
[[Category:2Fix]]