ASTM_D_6789_-_02.pdf

Designation:D 6789 02Standard Test Method forAccelerated Light Aging of Printing and Writing Paper byXenon-Arc Exposure Apparatus1This standard is issued under the fixed designation D 6789;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(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method describes a laboratory procedure forthe exposure of printing and writing paper to xenon-arc light atelevated levels of light flux to permit accelerated aging of thattype of paper.1.2 This test method specifies the sample preparation andconditions of exposure required to obtain information on therelative stability of paper with regard to change in opticalproperties brought about by exposure of such paper to light.1.3 This test method provides qualitative results regardingpaper stability and does not define the life expectancy for agiven paper to reach a specified set of optical properties.1.4 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:D 685 Practice for Conditioning Paper and Paper Productsfor Testing2D 985 Test Method for Brightness of Pulp,Paper,andPaperboard(Directional Reflectance at 457 nm)2D 1968 Terminology Relating to Paper and Paper Products2G 113 Terminology Relating to Natural and ArtificialWeathering Tests of Nonmetallic Materials3G 151 Practice for Exposing Nonmetallic Materials in Ac-celerated Test Devices that Use Laboratory Light Sources3G 155 Practice for Operating Xenon Arc Light Apparatusfor Exposure of Nonmetallic Materials32.2TAPPI Test Methods:T 254 Cupriethylenediamine Disperse Viscosity of Pulp(Falling Ball Method)4T 524 Color of Paper and Paperboard(45/0 Geometry)4T 1206 Precision Statement for Test Methods43.Terminology3.1 DefinitionsDefinitions shall be in accordance withTerminology D 1968 or Terminology G 113.For terms used inthis specification which are not provided by TerminologyD 1968 or Terminology G 113,see the Dictionary of Paper.54.Summary of Test Method4.1 In this test method,light from a xenon-arc lamp thatmakes use of filters to simulate natural daylight that has passedthrough window glass is shone on a paper surface with lightflux that is substantially greater than in normal indoor condi-tions of paper exposure.The light flux is applied in a controlledmanner and for a specified period of time.The light flux causesphotochemical reactions in the paper that change its reflectance(brightness)and color.By comparing initial and final levels ofthese parameters against difference criteria,a measure ofoptical stability is obtained.5.Significance and Use5.1 This test method will find use by parties concernedabout the relative optical stability of various printing andwriting papers.5.2 The test will provide manufacturers,paper users andother interested parties with quantified rankings of paperstability that identify papers that are stable,moderately stableand unstable when exposed to light over periods of time.5.3 The stability rankings may be used for definition of therelative stability of papers to light exposure,but will not definespecific periods of life expectancy of a given paper.6.Apparatus6.1 Provide a test chamber that utilizes a sealed“long-arc”xenon lamp to illuminate the test samples.The lamp spectrumshall be in accordance with Practice G 155,as per Table 2 ofthat document.6.2 Use a glass filtration system in front of the lamp tosimulate natural daylight that has passed through windowglass.This is to cut off almost all of the very short wavelength1This test method is under the jurisdiction of ASTM Committee D06 on Paperand Paper Products and is the direct responsibility of Subcommittee D06.92 on TestMethods.Current edition approved Oct.10,2002.Published December 2002.2Annual Book of ASTM Standards,Vol 15.09.3Annual Book of ASTM Standards,Vol 14.04.4Available from Technical Association of the Pulp and Paper Industry(TAPPI),P.O.Box 105113,Atlanta,GA30348;15 Technology Parkway South,Norcross,GA30092.5Available from TAPPI,5th ed.,1996.1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.light(nominally that which is below 320 nm)as occurs whendaylight passes through window glass.Provide the glassfiltration system as defined in Practice G 155.6.3 Provide a cooling system with the instrument such thattemperature at the paper surface is maintained at$20C and#30C for all paper types.Air may be used as a coolingmedium,but is not mandated so long as relative humidity ofabout 0.007 kg water/kg of dry air is maintained in theatmosphere above the paper s