Designation:F1425−06(Reapproved2011)StandardTestMethodforDeterminingtheTribochargeofTwo-ComponentDeveloperMaterials1ThisstandardisissuedunderthefixeddesignationF1425;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethoddescribesatechniqueformeasuringthetribochargeorcharge-to-massratioofasampleofdevel-opermaterial.1.2Thistestmethoddeterminestheconcentrationoftonerinasampleofdevelopermaterial.2.ReferencedDocuments2.1ASTMStandards:2F335TerminologyRelatingtoElectrostaticImaging3.Terminology3.1DefinitionsofTermsSpecifictoThisStandard:3.1.1chargetomassratio—thequantityofchargeperunitofmass.Inxerography,thetribochargeperunitofmassofthetoner.3.1.2tribocharge—thegeneraltermfortheelectricchargeofamaterialwhosechargeiscreatedbythetriboelectriceffect,ortherubbingofunlikesurfacestogether.3.2TermsanddefinitionsusedinthistestmethodmaybefoundinTerminologyF335.4.SummaryofTestMethod4.1Twocomponentdevelopermaterialsusedinthexero-graphicprocessarechargedbythetriboelectriceffect.Xerographicdevelopersarecommonlymadeupoftwomate-rials:tonerandcarrier.Tonersaretypicallyunder38µminsizewhilecarriersareseveraltimeslarger.Thissizedifferenceisusedinthemeasurementoftribocharge.4.2Thesamplecellcontainsaveryfinescreen(400mesh),whichallowstonertopassthroughandblockscarrierfrompassingthrough.Thesamplecellisheldinaninsulatedblockwithanelectricalconnectionbetweenthesamplecellandtheelectrometer.Theelectrometermeasuresthechargeonthecellasthetonerisblownoffthecarrierbyahighpressureairstream.Fromthedifferenceinweightofthecellbeforeandaftertheblow-off,andtheelectrometerchargemeasurement,thechargetomassratioandpercenttonerconcentrationofthedevelopermaterialcanbecalculated.5.SignificanceandUse5.1Thistestmethodmeasuresafundamentalpropertyofatoneranddevelopermixusedincopiersandpri...
