Editing Xylene (section)

==Applications==

===Terephthalic acid and related derivatives===
''p''-Xylene is the principal precursor to [[terephthalic acid]] and [[dimethyl terephthalate]], both [[monomer]]s used in the production of [[polyethylene terephthalate]] (PET) [[plastic bottle]]s and [[polyester]] clothing. 98% of ''p''-xylene production, and half of all xylenes produced is consumed in this manner.<ref name="Sweden" /><ref>ICIS, [http://www.icis.com/chemicals/paraxylene-orthoxylene/ Paraxylene-Orthoxylene {{pipe}} Prices, News & Market Analysis], icis.com, 2012. Accessed 2012-04-28.</ref> ''o''-Xylene is an important precursor to [[phthalic anhydride]]. The demand for [[isophthalic acid]] is relatively modest, so ''m''-xylene is rarely sought (and hence the utility of its conversion to the ''o''- and ''p''-isomers).

===Solvent applications and industrial purposes ===
Xylenes are used as a solvent in [[printing]], [[rubber]], and [[leather]] industries. It is a common component of ink, [[rubber]], and [[adhesive]]s.<ref>Bostik, [http://www.bostik-amer.com/upload/download/MSDS%20Blu%20Tack.pdf Safety Data Sheet Blu-Tack] ({{webarchive |url=https://web.archive.org/web/20110911020151/http://www.bostik-amer.com/upload/download/MSDS%20Blu%20Tack.pdf |date=September 11, 2011 }}), No. 13135, Bostik Corp., June 2007. Accessed 2012-04-28.</ref> In thinning [[paint]]s and [[varnish]]es, it can be substituted for [[toluene]] where slower drying is desired, and thus is used by [[conservator-restorer|conservators]] of art objects in solubility testing.<ref>Samet, Wendy, (comp.), [http://www.conservation-wiki.com/index.php?title=Appendix_I Appendix I, Painting Conservation Catalog], American Institute for Conservation of Historic and Artistic Works, conservation-wiki.com, September 1997. Accessed 2012-04-28.</ref> Similarly it is a [[cleaning agent]], e.g., for [[steel]], [[silicon wafer]]s, and [[integrated circuit]]s. In dentistry, xylene can be used to dissolve [[gutta percha]], a material used for endodontics (root-canal treatments). In the petroleum industry, xylene is also a frequent component of paraffin solvents, used when the tubing becomes clogged with paraffin wax.

===Laboratory use===
Xylene is used in the laboratory to make baths with dry ice to cool reaction vessels,<ref>{{cite web |title=Cooling baths |url=http://chemwiki.ucdavis.edu/Reference/Lab_Techniques/Cooling_baths |publisher=UC Davis Chem Wiki |access-date=8 February 2015 |date=2013-10-02 |archive-date=2015-02-08 |archive-url=https://web.archive.org/web/20150208042031/http://chemwiki.ucdavis.edu/Reference/Lab_Techniques/Cooling_baths |url-status=dead }}</ref> and as a [[solvent]] to remove synthetic [[immersion oil]] from the microscope [[objective (optics)|objective]] in [[optical microscope|light microscopy]].<ref>{{Citation |last = Cargille |first = John |title = Immersion Oil and the Microscope |journal = New York Microscopical Society Yearbook |orig-year = 1964 |year = 1985 |url = http://www.cargille.com/immersionoilmicroscope.shtml |access-date = 2011-03-10 |archive-url = https://web.archive.org/web/20110911190610/http://www.cargille.com/immersionoilmicroscope.shtml |archive-date = 2011-09-11 |url-status = dead }}</ref> In [[histology]], xylene is the most widely used clearing agent.<ref>{{cite book |title=Histotechnology: A Self-Instructional Text |last1=Carson |first1=Freida |last2=Hladik |first2=Christa |edition=3 |year=2009 |publisher=[[American Society for Clinical Pathology]] Press |isbn=9780891895817 |page=35 }}</ref> Xylene is used to remove paraffin from dried microscope slides prior to staining. After staining, microscope slides are put in xylene prior to mounting with a coverslip.

===Precursor to other compounds===
In one large-scale application, para-xylene is converted to [[terephthalic acid]]. The major application of ortho-xylene is as a precursor to [[phthalate ester]]s, used as [[plasticizer]]. Meta-xylene is converted to [[isophthalic acid]] derivatives, which are components of [[alkyd resin]]s.<ref name="Ullmann"/>