Designation:D918–99(Reapproved2003)AnAmericanNationalStandardTechnicalAssociationofPulpandPaperIndustryStandardMethodT477m-47StandardTestMethodforBlockingResistanceofPaperandPaperboard1ThisstandardisissuedunderthefixeddesignationD918;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodcoversthedeterminationoftheblock-ingresistanceofflexibletypesofpackagingmaterials,includ-ingpaper,andtheimpregnated,coatedorlaminated,orcoatedandlaminated,combinationsofpaperwithmetallicfoilsandsyntheticfilmsthatmaybeproducedtherefrom,butisappli-cabletopapersingeneral,wheneveratendencytoblockisimportant.Thetestmethodprovidesarangeofstandardconditionsoftemperatureandrelativehumidityatconstantpressureforaspecifiedtimewhichisdesignedtosimulatevaryingclimaticconditionsthatmaybeencounteredinthemanufacture,storage,transportation,oruseofthematerials.1.2Thevaluesstatedininch-poundunitsaretoberegardedasthestandard.Thevaluesinparenthesesareforinformationonly.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2D585PracticeforSamplingandAcceptingaSingleLotofPaper,Paperboard,Fiberboard,andRelatedProductsD685PracticeforConditioningPaperandPaperProductsforTestingD1968TerminologyRelatingtoPaperandPaperProducts3.Terminology3.1Definitions:DefinitionsshallbeinaccordancewithTerminologyD1968andtheDictionaryofPaper.34.Apparatus4.1Oven—Aconstant-temperatureoventhatcanbemain-tainedatselectedtemperaturesbetween100and140°F(38and67°C)within62°F(1°C).4.2Desiccator—Adesiccator,foruseashumiditychamber,havingaminimumdiameterof6in.(152mm).Ground-glassedgessho...
