Editing Polyimide (section)

=== Insulation and passivation films===
Polyimide materials are lightweight, flexible, resistant to heat and chemicals. Therefore, they are used in the [[electronics industry]] for flexible cables and as an insulating film on [[magnet wire]]. For example, in a laptop computer, the cable that connects the main logic board to the display (which must flex every time the laptop is opened or closed) is often a polyimide base with copper conductors. Examples of polyimide films include Apical, [[Kapton]], [[UPILEX]], VTEC PI, Norton TH and Kaptrex.
[[Image:Poly-oxydiphenylene-pyromellitimide.svg|thumb|Structure of poly-oxydiphenylene-pyromellitimide, "Kapton".]]

Polyimide is used to coat [[optical fiber#Coatings|optical fibers]] for medical or high temperature applications.<ref>{{Cite book|doi=10.1117/12.2210957|chapter=Mechanical properties of polyimide coated optical fibers at elevated temperatures|title=Optical Fibers and Sensors for Medical Diagnostics and Treatment Applications XVI|volume=9702|pages=97020Y|year=2016|last1=Huang|first1=Lei|last2=Dyer|first2=Robert S.|last3=Lago|first3=Ralph J.|last4=Stolov|first4=Andrei A.|last5=Li|first5=Jie|s2cid=123400822|editor1-first=Israel|editor1-last=Gannot}}</ref>

An additional use of polyimide resin is as an insulating and [[Passivation (chemistry)|passivation]]<ref>{{cite journal|doi=10.1023/A:1012802117916|year=2001|last1=Jiang|first1=Jiann-Shan|journal=Journal of Materials Science: Materials in Electronics|volume=12|issue=11|pages=655–659|title=The effect of polyimide passivation on the electromigration of Cu multilayer interconnections|last2=Chiou|first2=Bi-Shiou|s2cid=136747058}}</ref> layer in the manufacture of [[Integrated circuit]]s and [[MEMs|MEMS chip]]s. The polyimide layers have good mechanical elongation and tensile strength, which also helps the adhesion between the polyimide layers or between polyimide layer and deposited metal layer. The minimum interaction between the gold film and the polyimide film, coupled with high temperature stability of the polyimide film, results in a system that provides reliable insulation when subjected to various types of environmental stresses.<ref>Krakauer, David (December 2006) [http://www.analog.com/library/analogdialogue/archives/40-12/iso_power.html Digital Isolation Offers Compact, Low-Cost Solutions to Challenging Design Problems]. analog.com</ref><ref>Chen, Baoxing. [http://www.analog.com/static/imported-files/overviews/isoPower.pdf iCoupler Products with isoPower Technology: Signal and Power Transfer Across Isolation Barrier Using Microtransformers]. analog.com</ref> Polyimide is also used as a substrate for cellphone antennas.<ref>{{Cite web|url=https://appleinsider.com/articles/17/12/02/apple-to-adopt-speedy-lcp-circuit-board-tech-across-major-product-lines-in-2018|title = Apple to adopt speedy LCP circuit board tech across major product lines in 2018}}</ref>

Multi-layer insulation used on [[spacecraft]] is usually made of polyimide coated with thin layers of [[aluminum]], silver, gold, or germanium. The gold-colored material often seen on the outside of spacecraft is typically actually single aluminized polyimide, with the single layer of aluminum facing in.<ref>{{cite web|title=Thermal Control Overview|url=http://www.sheldahl.com/Documents/Aerospace/Thermal%20Control%20Overview.pdf|website=Sheldahl Multi Layer Insulation|access-date=28 December 2015}}</ref> The yellowish-brown polyimide gives the surface its gold-like color.