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'[[File:Blintzes in frying pan.jpg|thumb|right|Food in a non-stick pan]] A '''non-stick surface''' is a surface engineered to reduce the ability of other materials to stick to it. Non-stick cookware is a common application, where the non-stick coating allows food to brown without sticking to the pan. Non-stick is often used to refer to surfaces coated with [[polytetrafluoroethylene|polytetrafluoroethylene (PTFE)]], a well-known brand of which is "[[Teflon]]." In the twenty-first century other coatings have been marketed as non-stick, such as [[Anodizing#Anodized aluminium|anodized aluminium]], [[Ceramic materials|ceramics]], [[silicone]], [[Cast-iron cookware#Enameled cast iron|enameled cast iron]], and [[Seasoning (cookware)|seasoned cookware]]. [[Superhydrophobic coating]] is the newest non-stick coating for sale. ==History== ===Ancient Greece=== The [[Mycenaeans|Mycenaean Greeks]] might have used non-stick pans to make bread more than 3,000 years ago. Mycenaean ceramic griddles had one smooth side and one side covered with tiny holes like your moms vagene. The bread was probably placed on the side with the holes, since the dough tended to stick when cooked on the smooth side of the pan. The holes seem to be an ancient non-sticking technology, ensuring that oil spread evenly over the griddle.<ref>[http://www.livescience.com/42414-ancient-cooking-mycenaeans-portable-grills.html Ancient Greeks Used Portable Grills at Their Picnics], LiveScience</ref><ref>[http://www.archaeology.org/news/1707-140109-mycenaean-souvlaki-tray How to Cook Like a Mycenaean], Archaeology Magazine</ref> ===Modern development=== The modern non-stick pans were made using a coating of Teflon (polytetrafluoroethylene or PTFE). PTFE was invented [[Serendipity|serendipitously]] by [[Roy Plunkett]] in 1938,<ref name="Profile">{{cite web| title= Roy J. Plunkett |url=https://www.sciencehistory.org/historical-profile/roy-j-plunkett|website= [[Science History Institute]]|accessdate=21 February 2018}}</ref><ref name="OH">{{cite web|author=Center for Oral History| title= Roy J. Plunkett |url=https://oh.sciencehistory.org/oral-histories/plunkett-roy-j|website= [[Science History Institute]]|accessdate=21 February 2018}}</ref> while working for a joint venture of the [[DuPont]] company. The substance was found to have several unique properties, including very good corrosion-resistance and the lowest coefficient of friction of any substance yet manufactured. PTFE was first used to make seals resistant to the [[uranium hexafluoride]] gas used in development of the [[atomic bomb]] during [[World War II]], and was regarded as a military secret. Dupont registered the Teflon trademark in 1944 and soon began planning for post-war commercial use of the new product.<ref name="IandTmag">{{cite journal|journal=[[Invention and Technology Magazine]]|author=Anne Cooper Funderburg|title=Making Teflon Stick|series=Summer 2000|volume=16|issue=1|url=http://www.inventionandtech.com/content/making-teflon-stick-1|accessdate=2015-02-21}}</ref> By 1951 Dupont had developed applications for Teflon in commercial bread and cookie-making; however, the company avoided the market for consumer cookware due to potential problems associated with release of toxic gases if stove-top pans were overheated in inadequately ventilated spaces. While working at [[DuPont]], [[NYU Tandon School of Engineering]] alumnus John Gilbert was asked to evaluate a newly- developed material called Teflon. His experiments using the fluorinated polymer as a surface coating for pots and pans helped usher in a revolution in non-stick cookware.<ref>{{cite web|url=http://phys.org/news/2011-07-teflon-super-durable-proteins.html|title=Inspired by teflon, researchers create super durable proteins|publisher=}}</ref><ref>{{cite web|url=https://issuu.com/spark451/docs/invention_brochure/6|title=Invention, Innovation and Entrepreneurship Begin at the NYU Polytechnic School of Engineering|publisher=}}</ref> A few years later, a French engineer had begun coating his fishing gear with Teflon to prevent tangles. His wife Colette suggested using the same method to coat her cooking pans. The idea was successful and a French patent was granted for the process in 1954. The [[Tefal]] company was formed in 1956 to manufacture non-stick pans.<ref name="IandTmag" /> Not all non-stick pans use Teflon; other non-stick coatings have become available. For example, a mixture of [[titanium]] and [[ceramic]] can be [[sandblasting|sandblasted]] onto the pan surface, and then [[pottery firing|fired]] at {{convert|2000|C|F}} to produce a non-stick ceramic coating.<ref>{{cite encyclopaedia|encyclopedia=A to Z of Inventions and Inventors: M to P|article=Non-stick pan|author=Pennie Stoyles and Peter Pentland|pages=17|publisher=Black Rabbit Books|year=2007|isbn=9781583407899}}</ref> ==Examples== * Fluoropolymers ** [[Polytetrafluoroethylene]] (PTFE) ** [[Silverstone (plastic)]], a three-layer coating using PTFE and PFA * [[Superhydrophobic coating]]s are made from a variety of materials * [[Liquid-impregnated surface]] such as [[LiquiGlide]] ==PTFE (Teflon)== [[Polytetrafluoroethylene]] (PTFE) is a synthetic [[fluoropolymer]] used in various applications including non-stick coatings. Teflon is a brand of PTFE, often used as a generic term for PTFE. The metallic substrate is roughened by [[abrasive blasting]], then sometimes [[Thermal spraying|electric-arc sprayed]] with [[stainless steel]].<ref>Nicholas J. Wall, {{patent|US|5069937|"Thermal spraying of stainless steel"}}, 1988</ref><ref>Laurence W. McKeen, ''Fluorinated coatings and finishes handbook'', 2006, p. 117</ref> The irregular surface promotes adhesion of the PTFE and also resists abrasion of the PTFE.<ref>Excalibur brochure, [http://www.whitfordww.com/pdf/literature/Excalibur_2011.pdf PDF]</ref> Then one to seven layers of PTFE are sprayed or rolled on, with a larger number of layers and spraying being better. The number and thickness of the layers and quality of the material determine the quality of the non-stick coating.<ref>{{cite web |url=http://www.cookingforengineers.com/article/326/Whats-In-Your-Non-Stick/print |title=Cooking For Engineers |newspaper=Cookingforengineers.com |date= |author= |accessdate= 23 January 2016}}</ref> Better-quality coatings are more durable, and less likely to peel and flake, and keep their non-stick properties for longer. Any PTFE-based coating will rapidly lose its non-stick properties if overheated; all manufacturers recommend that temperatures be kept below, typically, {{Convert|260|C}}.<ref>{{cite web |url=https://www.chemours.com/Teflon/en_US/products/safety/cookware_safety.html |title=Cookware Safety by Teflon nonstick coatings |newspaper=Chemours Web site |date= |author= |accessdate= 23 January 2016}}</ref> Utensils used with PTFE-coated pans can scratch the coating, if the utensils are harder than the coating; this can be prevented by using non-metallic (usually plastic or wood) cooking tools. === Health concerns === When pans are overheated beyond approximately 350&nbsp;°C (660&nbsp;°F) the PTFE coating begins to dissociate, releasing byproducts (PFOA) which can cause [[polymer fume fever]] in humans and can be lethal to birds. Concerns have been raised over the possible negative effects of using PTFE-coated cooking pans.<ref name="IandTmag" /><ref>{{cite web |url=http://www.teflon.com/Teflon/teflonissafe/keyquestions.html#q2 |archiveurl=https://web.archive.org/web/20080117234907/http://www.teflon.com/Teflon/teflonissafe/keyquestions.html#q2 |archivedate=2008-01-17 |title=Safety of Teflon Non-Stick Coatings for Cookware|publisher=[[DuPont]]|accessdate=2009-05-06}}</ref><ref>American Cancer Society, [http://www.cancer.org/cancer/cancercauses/othercarcinogens/athome/teflon-and-perfluorooctanoic-acid--pfoa Teflon and Perfluorooctanoic Acid (PFOA)]</ref><ref>{{cite news|last=Tugend|first=Alina|title=Teflon Is Great for Politicians, but Is It Safe for Regular People?|url=https://www.nytimes.com/2006/10/14/business/14shortcuts.html?ref=teflon&_r=0|accessdate=15 September 2013|newspaper=New York Times|date=October 14, 2006}}</ref> Processing of PTFE in the past used to include [[Perfluorooctanoic acid]] (PFOA) as an emulsifier; however, PFOA is a [[persistent organic pollutant]] and poses both environmental and [[PFOA#Health concerns|health concerns]], and is now being phased out of use in PTFE processing.<ref>Juliet Eilperin: [https://www.washingtonpost.com/wp-dyn/content/article/2006/01/25/AR2006012502041.html ''Harmful Teflon Chemical To Be Eliminated by 2015'']. The Washington Post, 2006-01-26</ref> PFOA is now replaced by the GenX product manufactured by the DuPont spin-off Chemours, which seems to pose similar health issues as the now banned PFOA. == Culinary uses and limitations == With other types of pans, some [[Cooking oil|oil]] or fat is required to prevent hot food from sticking to the pan's surface. Food does not have the same tendency to stick to a non-stick surface; pans can be used with less, or no, oil, and are easier to clean, as residues do not stick to the surface. According to writer Tony Polombo, pans that are not non-stick are better for producing pan gravy, because the [[fond]] (the caramelized drippings that stick to the pan when meat is cooked) sticks to them, and can be turned into pan gravy by [[deglazing (cooking)|deglazing]] them&mdash;dissolving them in liquid.<ref>{{cite book|title=Cooking|chapter=Pots and Pans|author=Tony Polombo|pages=20|publisher=iUniverse|year=2006|isbn=9780595378661}}</ref> ==See also== *[[Cooking spray]] *[[Aluminium magnesium boride]] ==References== {{Reflist}} ==External links== * [http://home.howstuffworks.com/nonstick-cookware.htm How non-stick pan works] *[http://news.bbc.co.uk/1/hi/technology/3178136.stm "Science plans 'non-stick' submarine", ''bbc.co.uk'', 10 October, 2003] *[http://news.bbc.co.uk/2/hi/science/nature/6993719.stm "'Virtually non-stick' gum created", Rebecca Morelle and Liz Seward, ''BBC News'', 13 September 2007] *[http://home.howstuffworks.com/nonstick-cookware.htm How non-stick surface works- Illustration], from [[How Stuff Works]]. * [https://holscot.com/glossary/ptfe/ PTFE Properties] [[Category:Materials science]] [[Category:Cookware and bakeware]]'