coating

Coatings can be both decorative and have other functions.{{cite journal|last1=Howarth|first1=G A|last2=Manock|first2=H L|date=July 1997|title=Water-borne polyurethane dispersions and their use in functional coatings|journal=Surface Coatings International|volume=80|issue=7|pages=324–328|doi=10.1007/bf02692680|s2cid=137433262 |issn=1356-0751}} A pipe carrying water for a fire suppression system can be coated with a red (for identification) anticorrosion paint. Most coatings to some extent protect the substrate, such as maintenance coatings for metals and concrete.{{Cite book|last=Howarth|first=G.A|title=Waterborne Maintenance Systems for Concrete and Metal Structures|publisher=The Royal Society of Chemistry|year=1995|isbn=0-85404-740-9|editor-last=Karsa|editor-first=D.R|volume=165|location=Cambridge, U.K|chapter=5|editor-last2=Davies|editor-first2=W.D}} A decorative coating can offer a particular reflective property, such as high gloss, satin, matte, or flat appearance.{{Cite journal |last1=Akram |first1=Waseem |last2=Farhan Rafique |first2=Amer |last3=Maqsood |first3=Nabeel |last4=Khan |first4=Afzal |last5=Badshah |first5=Saeed |last6=Khan |first6=Rafi Ullah |date=2020-01-14 |title=Characterization of PTFE Film on 316L Stainless Steel Deposited through Spin Coating and Its Anticorrosion Performance in Multi Acidic Mediums |journal=Materials |language=en |volume=13 |issue=2 |pages=388 |doi=10.3390/ma13020388 |issn=1996-1944 |pmc=7014069 |pmid=31947700|bibcode=2020Mate...13..388A |doi-access=free }}

A major coating application is to protect metal from corrosion.{{Cite journal |last1=Li |first1=Jiao |last2=Bai |first2=Huanhuan |last3=Feng |first3=Zhiyuan |date=January 2023 |title=Advances in the Modification of Silane-Based Sol-Gel Coating to Improve the Corrosion Resistance of Magnesium Alloys |journal=Molecules |language=en |volume=28 |issue=6 |pages=2563 |doi=10.3390/molecules28062563 |pmid=36985537 |pmc=10055842 |issn=1420-3049|doi-access=free }}S. Grainger and J. Blunt, Engineering Coatings: Design and Application, Woodhead Publishing Ltd, UK, 2nd ed., 1998, {{ISBN|978-1-85573-369-5}}{{Cite journal |last1=Ramakrishnan |first1=T. |last2=Raja Karthikeyan |first2=K. |last3=Tamilselvan |first3=V. |last4=Sivakumar |first4=S. |last5=Gangodkar |first5=Durgaprasad |last6=Radha |first6=H. R. |last7=Narain Singh |first7=Anoop |last8=Asrat Waji |first8=Yosef |date=2022-01-13 |title=Study of Various Epoxy-Based Surface Coating Techniques for Anticorrosion Properties |journal=Advances in Materials Science and Engineering |language=en |volume=2022 |pages=e5285919 |doi=10.1155/2022/5285919 |issn=1687-8434|doi-access=free }}{{Cite journal|last1=Mutyala|first1=Kalyan C.|last2=Ghanbari|first2=E.|last3=Doll|first3=G.L.|date=August 2017|title=Effect of deposition method on tribological performance and corrosion resistance characteristics of Cr x N coatings deposited by physical vapor deposition|journal=Thin Solid Films|volume=636|pages=232–239|doi=10.1016/j.tsf.2017.06.013|bibcode=2017TSF...636..232M|issn=0040-6090|doi-access=free}}{{Cite journal |last1=Gao |first1=Mei-lian |last2=Wu |first2=Xiao-bo |last3=Gao |first3=Ping-ping |last4=Lei |first4=Ting |last5=Liu |first5=Chun-xuan |last6=Xie |first6=Zhi-yong |date=2019-11-01 |title=Properties of hydrophobic carbon–PTFE composite coating with high corrosion resistance by facile preparation on pure Ti |url=https://www.sciencedirect.com/science/article/pii/S1003632619651381 |journal=Transactions of Nonferrous Metals Society of China |language=en |volume=29 |issue=11 |pages=2321–2330 |doi=10.1016/S1003-6326(19)65138-1 |s2cid=213902777 |issn=1003-6326|url-access=subscription }} Automotive coatings are used to enhance the appearance and durability of vehicles. These include primers, basecoats, and clearcoats, primarily applied with spray guns and electrostatically.{{Cite web |last=Jaiswal |first=Vishal |title=Coating Process: Types, Applications, and Advantages |url=https://www.mechanicalsite.com/2023/05/coating-process.html |archive-url=https://web.archive.org/web/20230505150712/https://www.mechanicalsite.com/2023/05/coating-process.html |url-status=usurped |archive-date=May 5, 2023 |access-date=2023-05-05 |language=en}}

The body and underbody of automobiles receive some form of underbody coating.{{Cite web |title=Applying underbody sealant |url=https://www.howacarworks.com/bodywork/applying-underbody-sealant |access-date=2022-11-14 |website=How a Car Works |language=en}} Such anticorrosion coatings may use graphene in combination with water-based epoxies.{{Cite journal |last1=Monetta |first1=T. |last2=Acquesta |first2=A. |last3=Carangelo |first3=A. |last4=Bellucci |first4=F. |date=2018-09-01 |title=Considering the effect of graphene loading in water-based epoxy coatings |url=https://doi.org/10.1007/s11998-018-0045-8 |journal=Journal of Coatings Technology and Research |language=en |volume=15 |issue=5 |pages=923–931 |doi=10.1007/s11998-018-0045-8 |s2cid=139956928 |issn=1935-3804|url-access=subscription }}

Coatings are used to seal the surface of concrete, such as seamless polymer/resin flooring,{{Cite web |title=Polymer Flooring Systems For Industrial and Manufacturing Facilities |url=https://www.surfacesolutionsusa.com/flooring-solutions/polymer/ |access-date=2022-11-14 |website=Surface Solutions |language=en-US}}{{Cite web |title=Arizona Polymer Flooring {{!}} Industrial Epoxy Floor Coatings |url=https://www.apfepoxy.com/ |access-date=2022-11-14 |website=www.apfepoxy.com}}{{Cite patent|number=WO2016166361A1|title=Floor coating compositions|gdate=2016-10-20|invent1=WOLF|invent2=Thys|invent3=Brinkhuis|invent4=Subramanian|inventor1-first=Elwin Aloysius Cornelius Adrianus DE|inventor2-first=Ferry Ludovicus|inventor3-first=Richard Hendrikus Gerrit|inventor4-first=Ramesh|url=https://patents.google.com/patent/WO2016166361A1/en}}{{Cite book |chapter=Polymeric Floor Coatings |chapter-url=https://dl.asminternational.org/handbooks/edited-volume/13/chapter-abstract/139655/Polymeric-Floor-Coatings?redirectedFrom=fulltext |access-date=2022-11-14 |doi=10.31399/asm.hb.v05b.a0006037| title=Protective Organic Coatings | year=2015 | last1=Gelfant | first1=Frederick | pages=139–151 | isbn=978-1-62708-172-6 }}Ateya, Taher & Balcı, Bekir & Bayraktar, Oğuzhan & Kaplan, Gökhan. (2019). Floor Coating Materials. bund wall/containment lining, waterproofing and damp proofing concrete walls, and bridge decks.{{Cite book |last1=O’Reilly |first1=Matthew |last2=Darwin |first2=David |last3=Browning |first3=JoAnn |last4=Locke |first4=Carl E. |date=January 2011 |title=Evaluation of Multiple Corrosion Protection Systems for Reinforced Concrete Bridge Decks |url=https://kuscholarworks.ku.edu/handle/1808/19840 |language=en}}{{Cite journal |last1=Weyers |first1=Richard E. |last2=Cady |first2=Philip D. |date=1987-01-01 |title=Deterioration of Concrete Bridge Decks from Corrosion of Reinforcing Steel |url=https://www.concrete.org/publications/internationalconcreteabstractsportal/m/details/id/1959 |journal=Concrete International |language=English |volume=9 |issue=1 |issn=0162-4075}}{{Cite journal |last1=Grace |first1=Nabil |last2=Hanson |first2=James |last3=AbdelMessih |first3=Hany |date=2004-10-01 |title=Inspection and Deterioration of Bridge Decks Constructed Using Stay-In-Place Metal Forms and Epoxy-Coated Reinforcement |url=https://digitalcommons.calpoly.edu/cenv_fac/138 |journal=Civil and Environmental Engineering}}{{Cite book |last1=Babaei |first1=K |url=http://onlinepubs.trb.org/Onlinepubs/nchrp/nchrp_rpt_297.pdf |title=EVALUATION OF BRIDGE DECK PROTECTIVE STRATEGIES |last2=Hawkins |first2=N.M |publisher=Transportation Research Board |year=1987 |isbn=0-309-04566-5 |location=Washington DC |issn=0077-5614}} Compare with tradition coatings, moisture curing polyurethane has been widely used because of the excellent adaptability and ease of construction. The mechanical properties could be enhanced by introducing multiple hydrogen bonds and optimize the microphase separation structure.{{Cite journal |last=Li |first=Weijie |last2=Yao |first2=Guangxin |last3=Mo |first3=Ruibin |last4=Liu |first4=Weiwei |last5=Jiang |first5=Xiang |last6=Zhang |first6=Xinya |title=Bioinspired Robust Mechanical and Waterproofing Properties of Moisture-Curing Polyurethane With Multiple Hydrogen Bonding Networks |url=https://onlinelibrary.wiley.com/doi/10.1002/app.57112 |journal=Journal of Applied Polymer Science |language=en |volume=n/a |issue=n/a |pages=e57112 |doi=10.1002/app.57112 |issn=1097-4628|url-access=subscription }}

Most roof coatings are designed primarily for waterproofing, though sun reflection (to reduce heating and cooling) may also be a consideration. They tend to be elastomeric to allow for movement of the roof without cracking within the coating membrane.{{cite web |title=History of Liquid Waterproofing |url=http://www.lrwa.org.uk/History-of-Liquid-Waterproofing |url-status=dead |archiveurl=https://web.archive.org/web/20111001231035/http://www.lrwa.org.uk/History-of-Liquid-Waterproofing |archivedate=1 October 2011 |accessdate=12 September 2011 |publisher=Liquid Roofing and Waterproofing Association}}{{cite web|title=Liquid-Applied Monolithic Membrane Systems|url=http://www.roofcoatings.org/product.html#coldapplied|publisher=Roof Coatings Manufacturers Association|accessdate=12 September 2011}}{{cite web|title=The benefits of liquid roofing |url=http://www.lrwa.org.uk/Why-use-Liquid-Waterproofing |work=Why use liquid waterproofing |publisher=Liquid Roofing & Waterproofing Association |accessdate=12 September 2011 |url-status=dead |archiveurl=https://web.archive.org/web/20111001231232/http://www.lrwa.org.uk/Why-use-Liquid-Waterproofing |archivedate= 1 October 2011 }}

Wood has been a key material in construction since ancient times, so its preservation by coating has received much attention.{{Cite journal |last=Rowell |first=Roger M. |date=2021-07-31 |title=Understanding Wood Surface Chemistry and Approaches to Modification: A Review |journal=Polymers |language=en |volume=13 |issue=15 |pages=2558 |doi=10.3390/polym13152558 |issn=2073-4360 |pmc=8348385 |pmid=34372161|doi-access=free }} Efforts to improve the performance of wood coatings continue.{{Cite patent|number=WO2014190515A1|title=Wood coating composition|gdate=2014-12-04|invent1=Yang|invent2=Xu|invent3=Xu|invent4=ZHENG|inventor1-first=Xiaohong|inventor2-first=Jianming|inventor3-first=Yawei|inventor4-first=Baoqing|url=https://patents.google.com/patent/WO2014190515A1/en}}{{Cite journal |last1=Hazir |first1=Ender |last2=Koc |first2=Kücük Huseyin |last3=Hazir |first3=Ender |last4=Koc |first4=Kücük Huseyin |date=December 2019 |title=Evaluation of wood surface coating performance using water based, solvent based and powder coating |url=http://www.scielo.cl/scielo.php?script=sci_abstract&pid=S0718-221X2019000400467&lng=en&nrm=iso&tlng=en |journal=Maderas. Ciencia y tecnología |volume=21 |issue=4 |pages=467–480 |doi=10.4067/S0718-221X2019005000404 |s2cid=198185614 |issn=0718-221X|doi-access=free }}{{Cite journal |last1=Désor |first1=D. |last2=Krieger |first2=S. |last3=Apitz |first3=G. |last4=Kuropka |first4=R. |date=1999-10-01 |title=Water-borne acrylic dispersions for industrial wood coatings |url=https://doi.org/10.1007/BF02692644 |journal=Surface Coatings International |language=en |volume=82 |issue=10 |pages=488–496 |doi=10.1007/BF02692644 |s2cid=135745347 |issn=1356-0751|url-access=subscription }}{{Cite journal |last1=Podgorski |first1=L. |last2=Roux |first2=M. |date=1999-12-01 |title=Wood modification to improve the durability of coatings |url=https://doi.org/10.1007/BF02692672 |journal=Surface Coatings International |language=en |volume=82 |issue=12 |pages=590–596 |doi=10.1007/BF02692672 |s2cid=138555194 |issn=1356-0751|url-access=subscription }}{{Cite journal |last1=Žigon |first1=Jure |last2=Kovač |first2=Janez |last3=Petrič |first3=Marko |date=2022-01-01 |title=The influence of mechanical, physical and chemical pre-treatment processes of wood surface on the relationships of wood with a waterborne opaque coating |journal=Progress in Organic Coatings |language=en |volume=162 |pages=106574 |doi=10.1016/j.porgcoat.2021.106574 |s2cid=240200011 |issn=0300-9440|doi-access=free }}

Coatings are used to alter tribological properties and wear characteristics.{{Cite journal |last1=Tafreshi |first1=Mahshid |last2=Allahkaram |first2=Saeid Reza |last3=Mahdavi |first3=Soheil |date=2020-12-01 |title=Effect of PTFE on characteristics, corrosion, and tribological behavior of Zn–Ni electrodeposits |url=https://iopscience.iop.org/article/10.1088/2051-672X/ab9f05 |journal=Surface Topography: Metrology and Properties |volume=8 |issue=4 |pages=045013 |doi=10.1088/2051-672X/ab9f05 |bibcode=2020SuTMP...8d5013T |s2cid=225695450 |issn=2051-672X|url-access=subscription }}{{Cite journal |last1=Peng |first1=Shiguang |last2=Zhang |first2=Lin |last3=Xie |first3=Guoxin |last4=Guo |first4=Yue |last5=Si |first5=Lina |last6=Luo |first6=Jianbin |date=2019-09-01 |title=Friction and wear behavior of PTFE coatings modified with poly (methyl methacrylate) |url=https://www.sciencedirect.com/science/article/pii/S1359836818337119 |journal=Composites Part B: Engineering |language=en |volume=172 |pages=316–322 |doi=10.1016/j.compositesb.2019.04.047 |s2cid=155175532 |issn=1359-8368|url-access=subscription }} These include anti-friction, wear and scuffing resistance coatings for rolling-element bearings{{cite journal|last1=Mutyala|first1=Kalyan C.|last2=Singh|first2=Harpal|last3=Evans|first3=R. D.|last4=Doll|first4=G. L.|title=Effect of Diamond-Like Carbon Coatings on Ball Bearing Performance in Normal, Oil-Starved, and Debris-Damaged Conditions|journal=Tribology Transactions|date=23 June 2016|volume=59|issue=6|pages=1039–1047|doi=10.1080/10402004.2015.1131349|s2cid=138874627}}

Other functions of coatings include:

• Anti-fouling coatings{{Cite journal |last1=Cassé |first1=Franck |last2=Swain |first2=Geoffrey W. |date=2006-04-01 |title=The development of microfouling on four commercial antifouling coatings under static and dynamic immersion |url=https://www.sciencedirect.com/science/article/pii/S0964830506000394 |journal=International Biodeterioration & Biodegradation |language=en |volume=57 |issue=3 |pages=179–185 |doi=10.1016/j.ibiod.2006.02.008 |bibcode=2006IBiBi..57..179C |issn=0964-8305|url-access=subscription }}{{Cite journal |last1=Chambers |first1=L.D. |last2=Stokes |first2=K.R. |last3=Walsh |first3=F.C. |last4=Wood |first4=R.J.K. |date=December 2006 |title=Modern approaches to marine antifouling coatings |url=https://doi.org/10.1016/j.surfcoat.2006.08.129 |journal=Surface and Coatings Technology |volume=201 |issue=6 |pages=3642–3652 |doi=10.1016/j.surfcoat.2006.08.129 |issn=0257-8972}}{{Cite journal |last1=Yebra |first1=Diego Meseguer |last2=Kiil |first2=Søren |last3=Dam-Johansen |first3=Kim |date=2004-07-01 |title=Antifouling technology—past, present and future steps towards efficient and environmentally friendly antifouling coatings |url=https://www.sciencedirect.com/science/article/pii/S0300944003001644 |journal=Progress in Organic Coatings |language=en |volume=50 |issue=2 |pages=75–104 |doi=10.1016/j.porgcoat.2003.06.001 |issn=0300-9440|url-access=subscription }}
• Anti-microbial coatings.{{Cite journal |last1=Salwiczek |first1=Mario |last2=Qu |first2=Yue |last3=Gardiner |first3=James |last4=Strugnell |first4=Richard A. |last5=Lithgow |first5=Trevor |last6=McLean |first6=Keith M. |last7=Thissen |first7=Helmut |date=2014-02-01 |title=Emerging rules for effective antimicrobial coatings |url=https://www.cell.com/trends/biotechnology/abstract/S0167-7799(13)00207-2 |journal=Trends in Biotechnology |language=English |volume=32 |issue=2 |pages=82–90 |doi=10.1016/j.tibtech.2013.09.008 |issn=0167-7799 |pmid=24176168|url-access=subscription }}
• Anti-reflective coatings for example on spectacles.{{cite book | first=Jeffrey | last=Anshel | year=2005 | page=56 | title=Visual ergonomics handbook | publisher=CRC Press | isbn=1-56670-682-3}}
• Coatings that alter or have magnetic, electrical or electronic properties.{{Citation |last=Constantinides |first=Steve |title=Chapter 11 - Permanent magnet coatings and testing procedures |date=2022-01-01 |url=https://www.sciencedirect.com/science/article/pii/B978032388658100011X |work=Modern Permanent Magnets |pages=371–402 |editor-last=Croat |editor-first=John |series=Woodhead Publishing Series in Electronic and Optical Materials |publisher=Woodhead Publishing |language=en |doi=10.1016/b978-0-323-88658-1.00011-x |isbn=978-0-323-88658-1 |s2cid=246599451 |access-date=2022-11-14 |editor2-last=Ormerod |editor2-first=John|url-access=subscription }}{{Cite journal |last1=Biehl |first1=Philip |last2=Von der Lühe |first2=Moritz |last3=Dutz |first3=Silvio |last4=Schacher |first4=Felix H. |date=January 2018 |title=Synthesis, Characterization, and Applications of Magnetic Nanoparticles Featuring Polyzwitterionic Coatings |journal=Polymers |language=en |volume=10 |issue=1 |pages=91 |doi=10.3390/polym10010091 |issn=2073-4360 |pmc=6414908 |pmid=30966126|doi-access=free }}{{Cite journal |last1=Abdolrahimi |first1=Maryam |last2=Vasilakaki |first2=Marianna |last3=Slimani |first3=Sawssen |last4=Ntallis |first4=Nikolaos |last5=Varvaro |first5=Gaspare |last6=Laureti |first6=Sara |last7=Meneghini |first7=Carlo |last8=Trohidou |first8=Kalliopi N. |last9=Fiorani |first9=Dino |last10=Peddis |first10=Davide |date=July 2021 |title=Magnetism of Nanoparticles: Effect of the Organic Coating |journal=Nanomaterials |language=en |volume=11 |issue=7 |pages=1787 |doi=10.3390/nano11071787 |issn=2079-4991 |pmc=8308320 |pmid=34361173|doi-access=free }}
• Flame retardant coatings.{{Cite journal |last1=Liang |first1=Shuyu |last2=Neisius |first2=N. Matthias |last3=Gaan |first3=Sabyasachi |date=2013-11-01 |title=Recent developments in flame retardant polymeric coatings |url=https://www.sciencedirect.com/science/article/pii/S030094401300204X |journal=Progress in Organic Coatings |language=en |volume=76 |issue=11 |pages=1642–1665 |doi=10.1016/j.porgcoat.2013.07.014 |issn=0300-9440|url-access=subscription }}{{Cite journal |last1=Gu |first1=Jun-wei |last2=Zhang |first2=Guang-cheng |last3=Dong |first3=Shan-lai |last4=Zhang |first4=Qiu-yu |last5=Kong |first5=Jie |date=2007-06-25 |title=Study on preparation and fire-retardant mechanism analysis of intumescent flame-retardant coatings |url=https://www.sciencedirect.com/science/article/pii/S0257897207003349 |journal=Surface and Coatings Technology |language=en |volume=201 |issue=18 |pages=7835–7841 |doi=10.1016/j.surfcoat.2007.03.020 |issn=0257-8972|url-access=subscription }}{{Cite journal |last=Weil |first=Edward D. |date=May 2011 |title=Fire-Protective and Flame-Retardant Coatings - A State-of-the-Art Review |url=http://journals.sagepub.com/doi/10.1177/0734904110395469 |journal=Journal of Fire Sciences |language=en |volume=29 |issue=3 |pages=259–296 |doi=10.1177/0734904110395469 |s2cid=98415445 |issn=0734-9041|url-access=subscription }} Flame-retardant materials and coatings are being developed that are phosphorus and bio-based.{{Cite journal |last1=Naiker |first1=Vidhukrishnan E. |last2=Mestry |first2=Siddhesh |last3=Nirgude |first3=Tejal |last4=Gadgeel |first4=Arjit |last5=Mhaske |first5=S. T. |date=2023-01-01 |title=Recent developments in phosphorous-containing bio-based flame-retardant (FR) materials for coatings: an attentive review |url=https://doi.org/10.1007/s11998-022-00685-z |journal=Journal of Coatings Technology and Research |language=en |volume=20 |issue=1 |pages=113–139 |doi=10.1007/s11998-022-00685-z |s2cid=253349703 |issn=1935-3804|url-access=subscription }} These include coatings with intumescent functionality.{{Cite journal |last1=Puri |first1=Ravindra G. |last2=Khanna |first2=A. S. |date=2017-01-01 |title=Intumescent coatings: A review on recent progress |url=https://doi.org/10.1007/s11998-016-9815-3 |journal=Journal of Coatings Technology and Research |language=en |volume=14 |issue=1 |pages=1–20 |doi=10.1007/s11998-016-9815-3 |s2cid=138961125 |issn=1935-3804|url-access=subscription }}
• Non-stick PTFE coated cooking pots/pans.{{Cite journal |last=Thomas |first=P. |date=1998-12-01 |title=The use of fluoropolymers for non-stick cooking utensils |url=https://doi.org/10.1007/BF02693055 |journal=Surface Coatings International |language=en |volume=81 |issue=12 |pages=604–609 |doi=10.1007/BF02693055 |s2cid=98242721 |issn=1356-0751|url-access=subscription }}
• Optical coatings are available that alter optical properties of a material or object.{{Cite journal |last1=Yao |first1=Junyi |last2=Guan |first2=Yiyang |last3=Park |first3=Yunhwan |last4=Choi |first4=Yoon E |last5=Kim |first5=Hyun Soo |last6=Park |first6=Jaewon |date=2021-03-04 |title=Optimization of PTFE Coating on PDMS Surfaces for Inhibition of Hydrophobic Molecule Absorption for Increased Optical Detection Sensitivity |journal=Sensors |language=en |volume=21 |issue=5 |pages=1754 |doi=10.3390/s21051754 |issn=1424-8220 |pmc=7961674 |pmid=33806281|bibcode=2021Senso..21.1754Y |doi-access=free }}
• UV coatings{{Cite web |title=Radiation-Cured Coatings Continue to Experience Growth |url=https://www.coatingstech-digital.org/coatingstech/june_2021/MobilePagedArticle.action?articleId=1697302 |access-date=2022-11-14 |website=www.coatingstech-digital.org |language=en}}

File:PhotothermalCoatingThicknessGauges.jpg

Numerous destructive and non-destructive evaluation (NDE) methods exist for characterizing coatings.{{Cite journal |last=Walls |first=J. M. |date=1981-06-19 |title=The application of surface analytical techniques to thin films and surface coatings |url=https://dx.doi.org/10.1016/0040-6090%2881%2990224-8 |journal=Thin Solid Films |language=en |volume=80 |issue=1 |pages=213–220 |doi=10.1016/0040-6090(81)90224-8 |bibcode=1981TSF....80..213W |issn=0040-6090|url-access=subscription }}{{Cite journal |last=Benninghoven |first=A. |date=1976-12-01 |title=Characterization of coatings |url=https://dx.doi.org/10.1016/0040-6090%2876%2990620-9 |journal=Thin Solid Films |language=en |volume=39 |pages=3–23 |doi=10.1016/0040-6090(76)90620-9 |bibcode=1976TSF....39....3B |issn=0040-6090|url-access=subscription }}{{Cite journal |last1=Porter |first1=Stuart C. |last2=Felton |first2=Linda A. |date=2010-01-21 |title=Techniques to assess film coatings and evaluate film-coated products |url=https://doi.org/10.3109/03639040903433757 |journal=Drug Development and Industrial Pharmacy |volume=36 |issue=2 |pages=128–142 |doi=10.3109/03639040903433757 |issn=0363-9045 |pmid=20050727|s2cid=20645493 |url-access=subscription }}{{Cite journal |last=Doménech-Carbó |first=María Teresa |date=2008-07-28 |title=Novel analytical methods for characterising binding media and protective coatings in artworks |url=https://www.sciencedirect.com/science/article/pii/S0003267008009586 |journal=Analytica Chimica Acta |language=en |volume=621 |issue=2 |pages=109–139 |doi=10.1016/j.aca.2008.05.056 |pmid=18573376 |bibcode=2008AcAC..621..109D |issn=0003-2670|url-access=subscription }} The most common destructive method is microscopy of a mounted cross-section of the coating and its substrate.{{Cite journal |last1=Garcia-Ayuso |first1=G. |last2=Vázquez |first2=L. |last3=Martínez-Duart |first3=J. M. |date=1996-03-01 |title=Atomic force microscopy (AFM) morphological surface characterization of transparent gas barrier coatings on plastic films |url=https://dx.doi.org/10.1016/0257-8972%2895%2902712-2 |journal=Surface and Coatings Technology |language=en |volume=80 |issue=1 |pages=203–206 |doi=10.1016/0257-8972(95)02712-2 |issn=0257-8972|url-access=subscription }}{{Cite journal |last1=Caniglia |first1=Giada |last2=Kranz |first2=Christine |date=2020-09-01 |title=Scanning electrochemical microscopy and its potential for studying biofilms and antimicrobial coatings |url=https://doi.org/10.1007/s00216-020-02782-7 |journal=Analytical and Bioanalytical Chemistry |language=en |volume=412 |issue=24 |pages=6133–6148 |doi=10.1007/s00216-020-02782-7 |issn=1618-2650 |pmc=7442582 |pmid=32691088}}{{Cite journal |last1=Erich |first1=S. J. F. |last2=Laven |first2=J. |last3=Pel |first3=L. |last4=Huinink |first4=H. P. |last5=Kopinga |first5=K. |date=2005-03-01 |title=Comparison of NMR and confocal Raman microscopy as coatings research tools |url=https://www.sciencedirect.com/science/article/pii/S030094400400267X |journal=Progress in Organic Coatings |language=en |volume=52 |issue=3 |pages=210–216 |doi=10.1016/j.porgcoat.2004.12.002 |issn=0300-9440|url-access=subscription }} The most common non-destructive techniques include ultrasonic thickness measurement, X-ray fluorescence (XRF),{{Cite journal |last1=Revenko |first1=A. G. |last2=Tsvetyansky |first2=A. L. |last3=Eritenko |first3=A. N. |date=2022-08-01 |title=X-ray fluorescence analysis of solid-state films, layers, and coatings |url=https://www.sciencedirect.com/science/article/pii/S0969806X22001992 |journal=Radiation Physics and Chemistry |language=en |volume=197 |pages=110157 |doi=10.1016/j.radphyschem.2022.110157 |bibcode=2022RaPC..19710157R |s2cid=248276982 |issn=0969-806X|url-access=subscription }} X-Ray diffraction (XRD), photothermal coating thickness measurement{{Cite journal |last1=Schorr |first1=Brian S |last2=Stein |first2=Kevin J |last3=Marder |first3=Arnold R |date=1999-02-03 |title=Characterization of Thermal Spray Coatings |url=https://www.sciencedirect.com/science/article/pii/S1044580398000485 |journal=Materials Characterization |language=en |volume=42 |issue=2 |pages=93–100 |doi=10.1016/S1044-5803(98)00048-5 |issn=1044-5803|url-access=subscription }} and micro hardness indentation.{{Cite journal |last1=Martín Sánchez |first1=A. |last2=Nuevo |first2=M. J. |last3=Ojeda |first3=M. A. |last4=Guerra Millán |first4=S. |last5=Celestino |first5=S. |last6=Rodríguez González |first6=E. |date=2020-02-01 |title=Analytical techniques applied to the study of mortars and coatings from the Tartessic archaeological site "El Turuñuelo" (Spain) |url=https://www.sciencedirect.com/science/article/pii/S0969806X18313616 |journal=Radiation Physics and Chemistry |series=Special issue dedicated to the 14th International Symposium on Radiation Physics |language=en |volume=167 |pages=108341 |doi=10.1016/j.radphyschem.2019.05.031 |bibcode=2020RaPC..16708341M |s2cid=182324915 |issn=0969-806X|url-access=subscription }} X-ray photoelectron spectroscopy (XPS) is also a classical characterization method to investigate the chemical composition of the nanometer thick surface layer of a material.{{Cite journal |last1=Kravanja |first1=Katja Andrina |last2=Finšgar |first2=Matjaž |date=December 2021 |title=Analytical Techniques for the Characterization of Bioactive Coatings for Orthopaedic Implants |journal=Biomedicines |language=en |volume=9 |issue=12 |pages=1936 |doi=10.3390/biomedicines9121936 |issn=2227-9059 |pmc=8698289 |pmid=34944750|doi-access=free }} Scanning electron microscopy coupled with energy dispersive X-ray spectrometry (SEM-EDX, or SEM-EDS) allows to visualize the surface texture and to probe its elementary chemical composition.{{Cite journal |last1=Cook |first1=Desmond C. |date=2005-10-01 |title=Spectroscopic identification of protective and non-protective corrosion coatings on steel structures in marine environments |url=https://www.sciencedirect.com/science/article/pii/S0010938X05001186 |journal=Corrosion Science |series=International Symposium on Corrosion and Protection of Marine Structures—in memory of the late Professor Toshihei Misawa |language=en |volume=47 |issue=10 |pages=2550–2570 |doi=10.1016/j.corsci.2004.10.018 |bibcode=2005Corro..47.2550C |issn=0010-938X|url-access=subscription }} Other characterization methods include transmission electron microscopy (TEM), atomic force microscopy (AFM), scanning tunneling microscope (STM), and Rutherford backscattering spectrometry (RBS). Various methods of Chromatography are also used,{{Cite journal |last1=Lestido-Cardama |first1=Antía |last2=Vázquez-Loureiro |first2=Patricia |last3=Sendón |first3=Raquel |last4=Bustos |first4=Juana |last5=Santillana |first5=Mª Isabel |last6=Paseiro Losada |first6=Perfecto |last7=Rodríguez Bernaldo de Quirós |first7=Ana |date=January 2022 |title=Characterization of Polyester Coatings Intended for Food Contact by Different Analytical Techniques and Migration Testing by LC-MSn |journal=Polymers |language=en |volume=14 |issue=3 |pages=487 |doi=10.3390/polym14030487 |issn=2073-4360 |pmc=8839341 |pmid=35160476|doi-access=free }} as well as thermogravimetric analysis.{{Cite journal |last1=Mansfield |first1=Elisabeth |last2=Tyner |first2=Katherine M. |last3=Poling |first3=Christopher M. |last4=Blacklock |first4=Jenifer L. |date=2014-02-04 |title=Determination of Nanoparticle Surface Coatings and Nanoparticle Purity Using Microscale Thermogravimetric Analysis |url=https://pubs.acs.org/doi/10.1021/ac402888v |journal=Analytical Chemistry |language=en |volume=86 |issue=3 |pages=1478–1484 |doi=10.1021/ac402888v |pmid=24400715 |issn=0003-2700|url-access=subscription }}

The formulation of a coating depends primarily on the function required of the coating and also on aesthetics required such as color and gloss.{{Cite book |last=Müller |first=Bodo |url=https://www.worldcat.org/oclc/76886114 |title=Coatings formulation : an international textbook |date=2006 |publisher=Vincentz |others=Urlich Poth |isbn=3-87870-177-2 |location=Hannover |oclc=76886114}} The four primary ingredients are the resin (or binder), solvent which may be water (or solventless), pigment(s) and additives.{{example needed|date=February 2024}}{{Cite book|last=Müller|first=Bodo|url=https://www.worldcat.org/oclc/76886114|title=Coatings formulation : an international textbook|date=2006|publisher=Vincentz|others=Urlich Poth|isbn=3-87870-177-2|page=19|location=Hannover|oclc=76886114}}{{Cite web |title=CoatingsTech - Novel Natural Additives for Surface Coatings |url=https://www.coatingstech-digital.org/coatingstech/library/item/july_2022/4025808/ |access-date=2022-07-07 |website=www.coatingstech-digital.org |language=en}} Research is ongoing to remove heavy metals from coating formulations completely.{{Cite journal |last1=Puthran |first1=Dayanand |last2=Patil |first2=Dilip |date=2023-01-01 |title=Usage of heavy metal-free compounds in surface coatings |url=https://doi.org/10.1007/s11998-022-00648-4 |journal=Journal of Coatings Technology and Research |language=en |volume=20 |issue=1 |pages=87–112 |doi=10.1007/s11998-022-00648-4 |s2cid=251771272 |issn=1935-3804|url-access=subscription }}

For example, on the basis of experimental and epidemiological evidence, it has been classified by the IARC (International Agency for Research on Cancer) as a human carcinogen by inhalation (class I) ([https://www.sicurezza.com/ispesl ISPESL], 2008).{{Cite web |last1=Brizzi |first1=Luca |last2=Galbusera |first2=Federico |orig-date=academic year 2014-2015 |title="Riduzione in situ del cromo esavalente mediante iniezione di substrati organici in acquifero" |url=https://www.politesi.polimi.it/retrieve/a81cb05b-9e75-616b-e053-1605fe0a889a/2015_12_Brizzi_Galbusera.pdf}}

Coating processes may be classified as follows:

{{Main|Chemical vapor deposition}}

• Metalorganic vapour phase epitaxy
• Electrostatic spray assisted vapour deposition (ESAVD)
• Sherardizing
• Some forms of Epitaxy
• Molecular beam epitaxy

{{Main|Physical vapor deposition}}

• Cathodic arc deposition
• Electron beam physical vapor deposition (EBPVD)
• Ion plating
• Ion beam assisted deposition (IBAD)
• Magnetron sputtering
• Pulsed laser deposition
• Sputter deposition
• Vacuum deposition
• Vacuum evaporation, evaporation (deposition)
• Pulsed electron deposition (PED)

• Conversion coating
• Autophoretic, the registered trade name of a proprietary series of auto-depositing coatings specifically for ferrous metal substrates{{Cite book | doi = 10.4271/2000-01-0617| chapter = Epoxy Coatings for Automotive Corrosion Protection| year = 2000| last1 = Fristad | first1 = W. E. | title = SAE Technical Paper Series| volume = 1}}
• Anodising
• Chromate conversion coating
• Plasma electrolytic oxidation
• Phosphate (coating)
• Ion beam mixing
• Pickled and oiled, a type of plate steel coating
• Plating
• Electroless plating
• nickel plating coating using a different material to preserve mechanical properties{{Cite web |last=Zanier |first=Fabiana |title="Studio del processo di nichelatura chimica" |url=https://thesis.unipd.it/retrieve/b2309ec3-2fcc-4970-89ac-e50c42166fa1/STUDIO_DI_OTTIMIZZAZIONE_DI_UN_PROCESSO_DI_NICHELATURA_CHIMICA.pdf}}
• Electroplating

• Spray painting
• High velocity oxygen fuel (HVOF)
• Plasma spraying
• Thermal spraying
• Kinetic metallization (KM)
• Plasma transferred wire arc thermal spraying
• The common forms of Powder coating

Common roll-to-roll coating processes include:

• Air knife coating
• Anilox coater
• Flexo coater
• Gap Coating
• Knife-over-roll coating
• Gravure coating
• Hot melt coating- when the necessary coating viscosity is achieved by temperature rather than solution of the polymers etc. This method commonly implies slot-die coating above room temperature, but it also is possible to have hot-melt roller coating; hot-melt metering-rod coating, etc.
• Immersion dip coating
• Kiss coating
• Metering rod (Meyer bar) coating
• Roller coating
• Forward roller coating
• Reverse roll coating
• Silk Screen coater
• Rotary screen
• Slot Die coating - Slot die coating was originally developed in the 1950s.{{cite patent|title=Method of coating strip material |country=US|number=2681294 |gdate=1951-08-23}} Slot die coating has a low operational cost and is an easily scaled processing technique for depositing thin and uniform films rapidly, while minimizing material waste.{{Cite journal |last=Beeker |first=L.Y.|date=March 2018|title=Open-source parametric 3-D printed slot die system for thin film semiconductor processing |journal=Additive Manufacturing |volume=20 |pages=90–100 |doi=10.1016/j.addma.2017.12.004 |s2cid=86782023 |issn=2214-8604|url=https://hal.archives-ouvertes.fr/hal-02111388/file/Open-source_Parametric_3-D_Printed_Slot.pdf}} Slot die coating technology is used to deposit a variety of liquid chemistries onto substrates of various materials such as glass, metal, and polymers by precisely metering the process fluid and dispensing it at a controlled rate while the coating die is precisely moved relative to the substrate.{{Cite news|url=https://ntact.com/applications/slot-die-coating/|title=Slot Die Coating - nTact|work=nTact|access-date=2018-11-24|language=en-US}} The complex inner geometry of conventional slot dies require machining or can be accomplished with 3-D printing.{{Cite web|url=https://3dprintingindustry.com/news/open-source-3d-printing-cuts-cost-4000-0-25-says-new-study-127484/|title=Open Source 3D printing cuts cost from $4,000 to only $0.25 says new study - 3D Printing Industry|website=3dprintingindustry.com|date=16 January 2018 |language=en-US|access-date=2018-11-24}}
• Extrusion coating - generally high pressure, often high temperature, and with the web travelling much faster than the speed of the extruded polymer
• Curtain coating- low viscosity, with the slot vertically above the web and a gap between slot-die and web.
• Slide coating- bead coating with an angled slide between the slot-die and the bead. Commonly used for multilayer coating in the photographic industry.
• Slot die bead coating- typically with the web backed by a roller and a very small gap between slot-die and web.
• Tensioned-web slot-die coating- with no backing for the web.
• Inkjet printing
• Lithography
• Flexography

• Langmuir-Blodgett
• Spin coating
• Dip coating

{{Wiktionary}}

{{Div col|colwidth=}}

• Adhesion Tester
• Deposition
• Electrostatic coating
• Film coating drugs
• Food coating
• Formulations
• Langmuir-Blodgett film
• Nanoparticle deposition
• Optically active additive, for inspection purposes after a coating operation
• Paint
• Paper coating
• Plastic film
• Polymer science
• Printed electronics
• Seal (mechanical)
• Thermal barrier coating
• Thermal cleaning
• Thin-film deposition
• Thermosetting polymer
• Vitreous enamel

{{Div col end}}

{{Reflist}}

• {{Cite book |last=Müller |first=Bodo |url=https://www.worldcat.org/oclc/76886114 |title=Coatings formulation : an international textbook |date=2006 |publisher=Vincentz |others=Urlich Poth |isbn=3-87870-177-2 |location=Hannover |oclc=76886114}}
• {{Cite book |last=Spyrou |first=Emmanouil |url=https://www.worldcat.org/oclc/828194496 |title=Powder coatings chemistry and technology |date=2012 |publisher=Vincentz Network |isbn=978-3-86630-884-8 |edition=3|oclc=828194496}}
• Titanium and titanium alloys, edited by C. Leyens and M. Peters, Wiley-VCH, {{ISBN|3-527-30534-3}}, table 6.2: overview of several coating systems and fabriction processes for titanium alloys and titanium aluminides (amended)
• Coating Materials for Electronic Applications: Polymers, Processes, Reliability, Testing by James J. Licari; William Andrew Publishing, Elsevier, {{ISBN|0-8155-1492-1}}
• High-Performance Organic Coatings, ed. AS Khanna, Elsevier BV, 2015, {{ISBN|978-1-84569-265-0}}

{{Authority control}}

Category:Corrosion

Category:Materials science

Category:Printing