ASTM_D_7842_-_D_7842M_-_12_2021.pdf

Designation:D7842/D7842M12(Reapproved 2021)Standard Test Method forHolding Strength of Tack and Prong Fastener AttachedButtons1This standard is issued under the fixed designation D7842/D7842M;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of lastreapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the determination of the holdingstrength of a tack and prong fastener attached button using atensile testing machine.1.2 This test method is applicable to attached buttons ingarments or to be attached to fabrics intended for use in apparel(see Annex A1).1.3 UnitsThe values stated in either SI units or inch-pound units are to be regarded separately as standard.Thevalues stated in each system are not necessarily exact equiva-lents;therefore,to ensure conformance with the standard,eachsystem shall be used independently of the other,and valuesfrom the two systems shall not be combined.1.4 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.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:2D76/D76M Specification for Tensile Testing Machines forTextilesD123 Terminology Relating to TextilesD1776/D1776M Practice for Conditioning and Testing Tex-tiles2.2 Federal Document:316 CFR Parts 1500.48-1500.53 and 1501.4 Engineering TestManual for Childrens Toys3.Terminology3.1 Definitions:3.1.1 force,na physical influence exerted by one body onanother which produces acceleration of bodies that are free tomove and deformation of bodies that are not free to move.3.1.2 holding strength,nin buttons,the force required toseparate the button from its attached mating part or separatefrom the fabric it is attached to,whichever shall fail first.3.1.3 tack attached button,nany button that is attached bya single post product(most commonly used to attach a nonmetal colleted button).(See Fig.1.)3.1.4 prong fastener attached button,nany button that isattached by a product with 2 or more prongs(most commonlyused to attach a metal colleted button).(See Fig.2.)3.1.5 For definitions of other textile terms used in thisstandard,refer to Terminology D123.4.Summary of Test Method4.1 A specimen,consisting of a button and tack or prongfastener attached to a fabric,is mounted in a special test fixtureon a tensile testing machine.Aforce is applied perpendicularlyuntil the button separates from the tack or prong fastener,or thefabric is torn.The peak force at separation is reported as theholding strength.If the fabric tears,the peak force at fabricfailure is recorded and the data is reported and considered as adifferent category to be reported separately from the holdingstrength of the fasteners.5.Significance and Use5.1 This test method may be used for acceptance testing ofcommercial shipments of garments with attached buttons.5.2 This test method may be used to determine the compat-ibility of tack attached buttons or prong fastener attachedbuttons to fabrics used in apparel.In which case,the buttons1This test method is under the jurisdiction ofASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.54 on Subassemblies.Current edition approved July 1,2021.Published July 2021.Originally approvedin 2012.Last previous edition approved in 2016 as D7842/D7842M 12(2016).DOI:10.1520/D7842-12R21.2For 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.3Available from U.S.Government Publishing Office(GPO),732 N.Capitol St.,NW,Washington,DC 20401,http:/www.gpo.gov.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.1are attached to the fabric in the manner in which they will beused and the combined units tested.6.Apparatus6.1 Tensile Testing Machine,CRE type,meeting Specifica-tion D76/D76M.(See Fig.3.)6.1.1 Upper Test Fixture,Fig.4,designed as not