ASTM_D_5965_-_02_2013.pdf

Designation:D596502(Reapproved 2013)Standard Test Methods forSpecific Gravity of Coating Powders1This standard is issued under the fixed designation D5965;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 These test methods cover three procedures for determin-ing the specific gravity(see definition)of coating powders,asfollows:TEST METHOD AFor Testing Coating Powders,Excluding MetallicsTEST METHOD BFor Tests Requiring Greater Precision than Test Method A,Including Metallics,Using Helium PycnometryTEST METHOD CFor Theoretical Calculation Based on Raw Material SpecificGravities1.2 Test Method A can be used as a less expensive methodwith reduced accuracy for determining the specific gravity ofcoating powders,excluding metallics.1.3 The ideal gas law forms the basis for all calculationsused in the Test Method B determination of density of coatingpowders.1.4 Test Method B includes procedures that provided ac-ceptable results for samples analyzed during round robintesting.1.5 Test Method B uses SI units as standard.State allnumerical values in terms of SI units unless specific instru-mentation software reports surface area using alternate units.Many instruments report density as g/cm3,instead of using SIunits(kg/m3).1.6 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.7 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 and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D3924 Specification for Environment for Conditioning andTesting Paint,Varnish,Lacquer,and Related MaterialsD5382 Guide to Evaluation of Optical Properties of PowderCoatingsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Terminology3.1 Definitions:3.1.1 Definitions 3.1.1 and 3.1.3 are from Guide D5382.3.1.2 coating powder,nfinely divided particles of resin,either thermoplastic or thermosetting,generally incorporatingpigments,fillers,and additives and remaining finely dividedduring storage under suitable conditions,which,after fusingand possibly curing,give a continuous film.3.1.3 meniscus,ncurved upper surface of a liquid columnthat is concave when the containing walls are wetted by theliquid.3.1.4 powder coating,ncoatings which are protective ordecorative,or both,formed by the application of a coatingpowder to a substrate and fused into continuous films by theapplication of heat or radiant energy.3.1.5 pycnometer,ninstrument designed to measure thevolume of solid materials using Archimedes principle of fluiddisplacement.The displaced fluid is a helium gas.3.1.6 specific gravity(1)strict definition:the density of asubstance relative to that of water;(2)practical,as used in thistest methodThe numerical value of the density when thelatter is expressed in grams per millilitre.1These test methods are under the jurisdiction of ASTM Committee D01 onPaint and Related Coatings,Materials,and Applications and are the directresponsibility of Subcommittee D01.51 on Powder Coatings.Current edition approved June 1,2013.Published July 2013.Originally approvedin 1996.Last previous edition approved in 2007 as D5965 02(2007).DOI:10.1520/D5965-02R13.2For 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 States1 4.Significance and Use4.1 Test Method A is a less expensive method of determin-ing specific gravity of coating powders,excluding metallics,that produced less precise results than Test Method B.4.2 Test Method B provides better precision at higher costand includes metallics,although different models produceddifferent grand averages for each of the three samples tested.4.3 Test Method C is commonly used by the powder coatingindustry to estimate the coverage of a powder coating at agiven thickness,using the theoretical specific gravity calcu-lated from those of the raw materials.5.Reagents5.1 PurityWetting vehicles should be of reagent grades.5.2 HeliumShall be understood to mean high purity ofcommercial grade.6.Conditioning6.1 These tests should be standardized at 23 6 2C(73.5 63.5F)and relative humidity of 50 6 5%for the two methodsin compliance with Specification D3924.TEST METHOD AFOR TESTING POWDERCOATINGS,EXCLUDING METALLICS7.Apparatus and Materials7.1 Volumetric FlaskCalibrated narrow-necked glass