ASTM_F_3290_-_17.pdf

Designation:F329017Standard Guide forHandling and Application of a Membrane Switch or PrintedElectronic Device to its Final Support Structure1This standard is issued under the fixed designation F3290;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This guide covers proper handling and application of aflexible circuit membrane switch,or printed electronic assem-bly to its final support structure to avoid mechanical orelectrical failure.1.2 Damage of internal tactile devices or surface mountdevice(SMD)components can occur with excessive flexing orbending during lamination,repositioning,from uneven supportsurface,air entrapment,or pressing keys when unsupported.1.3 Design considerations and material selection can impactthe membrane switch or the printed electronic devices abilityto endure the mechanical stress that can occur in handling,application and use.These should be considered as early aspossible in the design phase.1.4 Recent advancements in printed electronic polymermaterials have shown increased reliability from flexing andcreasing,replacing copper flex circuits in many cases.1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2F2749 Test Method for Determining the Effects of Creasinga Membrane Switch or Printed Electronic DeviceF2750 Test Method for Determining the Effects of Bendinga Membrane Switch or Printed Electronic DeviceF3147 Test Method for Evaluating the Reliability of SurfaceMounted Device(SMD)Joints on a Flexible Circuit by aRolling Mandrel Bend3.Terminology3.1 Definitions:3.1.1 membrane switch(MS),na momentary switchingdevice in which at least one contact is on,or made of,a flexiblesubstrate.3.1.2 printed electronic device(PED),nelectrically func-tional device manufactured primarily using an additiveprocess,with or without attached conventional or other elec-tronic components,often in flexible format.4.Summary of Guide4.1 This guide provides recommendations or best practicesto prevent damage to membrane switches or printed electronicdevices from unsupported use or excessive stress during theapplication to the final supporting structure.5.Significance and Use5.1 Membrane switches or printed electronic devices aretested for function and aesthetically inspected by the manufac-turer before release to the end user.The user can unknowinglydamage the device beyond repair prior to,or during,theapplication(laminating)process.5.2 Awareness and proper techniques are essential to the enduser and this guide should be noted on all drawings,qualitycontrol documentation,and assembly instructions.Propertraining and practice must be provided to work area supervisorsand their staff.5.3 Concerning materials choice,consistency,and design inuse,it is important to know what to look for and how to designfor durability and to test for or prevent potential failures,orboth.5.4 Component failure due to handling damage is one of themost common causes of customer complaints.It is the endusers responsibility to ensure that the product is not damagedduring installation5.5 In the event of component failures a comparison of pre-and post-assembly test performance may help determine thecause of failure.Even if an acceptable change is noted,it maybe the result of the unit being over stressed and the application1This test method is under the jurisdiction of ASTM Committee F01 onElectronics and is the direct responsibility of Subcommittee F01.18 on PrintedElectronics.Current edition approved Nov.1,2017.Published November 2017.DOI:10.1520/F3290-17.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1 process should be reviewed and changed if necessary.It isimportant to determine if the change or failure is one thatshould have withstood the application process,or whether theapplication process is causing undue stress.Bend,Crease,andMandrel Testing in accordance with Test Methods F2