1、Designation:D629019Standard Test Method forColor Determination of Plastic Pellets1This standard is issued under the fixed designation D6290;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 parenth
2、eses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method is used for the instrumental measure-ment of the degree of yellowness(or change of degree ofyellowness)under daylight illumination of homo
3、geneous,nonfluorescent,nearly-colorless transparent or nearly-whitetranslucent or opaque plastics.The measurement is made onpellets and based on tristimulus values obtained with a spec-trophotometer or colorimeter.1.2 This test method is applicable to the color analysis ofplastic pellets.It is possi
4、ble that each material will have uniquecharacteristics that determine the color values.1.3 This procedure outlines a method to determine colormeasurements,such as Yellowness Index(YI),CIE X,Y,Z,and Hunter L,a,b,or CIE L*,a*,b*.1.4 The values stated in SI units are to be regarded as thestandard.The v
5、alues given in parentheses are for informationonly.1.5 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 applic
6、ability of regulatory limitations prior to use.NOTE1This standard and ISO 17223 address the same subject matterbut differ in technical content.1.6 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Pr
7、inciples 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:2D883 Terminology Relating to PlasticsD2244 Practice for Calculation of Color Tolerances andColo
8、r Differences from Instrumentally Measured ColorCoordinatesE179 Guide for Selection of Geometric Conditions forMeasurement of Reflection and Transmission Propertiesof MaterialsE284 Terminology of AppearanceE308 Practice for Computing the Colors of Objects by Usingthe CIE SystemE313 Practice for Calc
9、ulating Yellowness and WhitenessIndices from Instrumentally Measured Color CoordinatesE456 Terminology Relating to Quality and StatisticsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodE1331 Test Method for Reflectance Factor and Color bySpectrophotome
10、try Using Hemispherical GeometryE1347 Test Method for Color and Color-Difference Mea-surement by Tristimulus ColorimetryE1349 Test Method for Reflectance Factor and Color bySpectrophotometry Using Bidirectional(45:0 or 0:45)GeometryE2935 Practice for Conducting Equivalence Testing inLaboratory Appli
11、cations2.2 ISO/IEC Standards:ISO 17223 Plastics Determination of Yellowness Index andChange in Yellowness Index.CIE Standard D 001 Colorimetric Illuminants and Observers(Disk)(www.cie.co.at)3.Terminology3.1 DefinitionsRefer to Terminologies D883 and E284 fordefinitions of terms used in this test met
12、hod.4.Significance and Use4.1 Before proceeding with this test method,refer to thespecification of the material being tested.Any test specimenpreparation,conditioning,dimensions,or testing parameters,ora combination thereof,covered in the materials specificationshall take precedence over those menti
13、oned in this test method.If there are no material specifications,then default conditionsapply.NOTE2Some materials,such as polyamide(nylon),can be cooledvery differently during the production of the pellets.This variation in thecooling of the pellets can result in different levels of crystallinity in
14、 the1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.40 on Optical Properties.Current edition approved June 1,2019.Published June 2019.Originallyapproved in 1998.Last previous edition approved in 2018 as D6290-18.DOI:10
15、.1520/D6290-19.2For 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.*A Summary of Changes section appears at the end of
16、 this standardCopyright 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.1 pellets only.More crystalline nylons will be more opaque than