Designation:D4838−88(Reapproved2010)StandardTestMethodforDeterminingtheRelativeTintingStrengthofChromaticPaints1ThisstandardisissuedunderthefixeddesignationD4838;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethoddescribesthedeterminationoftheabsorptiontintingstrengthofachromatictestpaintrelativetothatofastandardorreferencepaintofthesamechemicaltype.Theproceduresarebasedondilutionofthepaintswithastandardmixingwhitepaint,followedbyinstrumentalmea-surementandcalculation.Provisionismadeforcorrectingtheresultsforsmalldifferencesinhueorchroma,orboth,betweenthetestandreferencechromaticpaints.1.2Thistestmethodisintendedforthecomparisonofpaintscontainingthesametypeofvehicle(acrylic,alkyd,oroil)andsingle-pigmentcolorantsofthesameColourIndex2nameandnumber.Theamountsofthepigmentandoftheothercomponentsofthepaintneednotbeknown.1.3ThevaluesstatedinSIunitsaretoberegardedasthestandard.Thevaluesgiveninparenthesesareforinformationonly.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:3D1640TestMethodsforDrying,Curing,orFilmFormationofOrganicCoatingsatRoomTemperatureD4303TestMethodsforLightfastnessofColorantsUsedinArtists’MaterialsE284TerminologyofAppearanceE308PracticeforComputingtheColorsofObjectsbyUsingtheCIESystemE1164PracticeforObtainingSpectrometricDataforObject-ColorEvaluation3.Terminology3.1Definitions:3.1.1tintingstrength,n—measureoftheeffectivenesswithwhichaunitquantityofacolorantaltersthecolorofamaterial.Forscatteringandabsorbingcolorants(pigments),bothab-sorptionandscatteringtintingstrengthmustbespecified.3.1.2tinti...
