ASTM_D_985_-_97_2007.pdf

Designation:D985 97(Reapproved 2007)An American National StandardStandard Test Method forBrightness of Pulp,Paper,and Paperboard(DirectionalReflectance at 457 nm)1This standard is issued under the fixed designation D985;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 This test method determines the brightness of white,near-white,and naturally colored pulp,paper,and paperboard.Brightness is a commonly used industry term for the numericalvalue of the reflectance factor of a sample,with respect to bluelight of specific spectral and geometric characteristics.This testmethod requires an instrument employing 45 illumination and0 viewing geometry,with the illuminating and viewing beamsadjusted so that translucent materials are evaluated on anarbitrary but specific scale(1-4).21.2 This test method is applicable to all naturally-coloredpulps,and papers and board made from pulps.The measure-ment is not suitable for paper and paperboard containing addedcoloring matter(such as yellow or green dyestuff)whichappreciably absorbs light in that part of the spectrum extendingfrom about 400 to 500 nm.Colored papers must be measuredspectrophotometrically or colorimetrically in order to obtainmeaningful results(TAPPI T 442,T 524,and T 527).This testmethod is,however,suitable for pulps or papers which containoptical(fluorescent)brightening agents.1.3 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:3D585 Practice for Sampling and Accepting a Single Lot ofPaper,Paperboard,Fiberboard,and Related ProductD1968 Terminology Relating to Paper and Paper Products2.2TAPPI Standards:4T 218 Forming handsheets for reflectance tests of pulpT 442 Spectral reflectance factor,transmittance and color ofpaper and pulp(Polychromatic illumination)T 452 Brightness of pulp,paper and paperboard(Direc-tional reflectance of 457 nm)T 524 Color of white and near-white paper and paperboardby L,a,b 45 0 colorimetryT 527Color of paper and paperboard in CIE systemT 1206 Precision statements for test methods3.Terminology3.1 DefinitionsDefinitions shall be in accordance withTerminology D1968 and the Dictionary of Paper.44.Summary of Test Method4.1 This test method provides the following:4.1.1 A scale for measurement of paper brightness(bluedirectional reflectance factor),4.1.2 A method for verifying the calibration of each instru-ment used for brightness testing so that the user can rely uponthe test results,and4.1.3 Criteria for the geometric,and photometric character-istics required by instruments employed in the use of this testmethod.4.2 A procedure is also described for separating the fluores-cent component of brightness from the non-fluorescent com-ponent of brightness and measuring it quantitatively.5.Significance and Use5.1 Brightness is the most extensively used optical propertyof pulp,paper,and paperboard.The measurement of brightness(blue reflectance)was originally devised as a means ofquantitatively assessing the effectiveness of pulp bleaching.Aspecific spectral response has been defined and rigorouslymaintained,providing longterm stability of brightness valuesto the industry.5.2 The accurate determination of brightness is of vitalimportance in the buy-sell relationship between the paper1This test method is under the jurisdiction of ASTM Committee D06 on Paperand Paper Products and is the direct responsibility of Subcommittee D06.92 onStandard Documents Relating to Paper and Paper Products.Current edition approved Dec.1,2007.Published December 2007.Originallyapproved in 1948.Last previous edition approved in 2002 as D985 97(2002).DOI:10.1520/D0985-97R07.2The boldface numbers in parentheses refer to the list of references at the end ofthis test method.3For 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.4Available from Technical Association of the Pulp and Paper Industry(TAPPI),15 Technology Parkway South,Norcross,GA 30092,http:/www.tappi.org.1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.NOTICE:This standard has either been superseded and replaced by a new version or withdrawn.Contact ASTM International(www.astm.org)for the latest information.producer and consumer.High brightness is an indication ofhigh-quality paper,resulting in a price structure where price isrelatively proportional to the br