ASTM_D_925_-_14.pdf

Designation:D92514Standard Test Methods forRubber PropertyStaining of Surfaces(Contact,Migration,and Diffusion)1This standard is issued under the fixed designation D925;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 techniques to evaluate threetypes of staining that rubber may cause when in contact with,or in proximity to,another surface that may be light colored.1.2 The test methods also describe how to qualitativelyevaluate the degree of staining produced under the conditionsof exposure to heat alone or heat and light.1.3 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.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:2D1148 TestMethodforRubberDeteriorationDiscoloration from Ultraviolet(UV)or UV/Visible Radia-tion and Heat Exposure of Light-Colored SurfacesD3182 Practice for RubberMaterials,Equipment,and Pro-cedures for Mixing Standard Compounds and PreparingStandard Vulcanized SheetsD3183 Practice for RubberPreparation of Pieces for TestPurposes from ProductsE145 Specification for Gravity-Convection and Forced-Ventilation OvensG151 Practice for Exposing Nonmetallic Materials inAccel-erated Test Devices that Use Laboratory Light SourcesG154 Practice for Operating Fluorescent Ultraviolet(UV)Lamp Apparatus for Exposure of Nonmetallic MaterialsG155 Practice for Operating Xenon Arc Light Apparatus forExposure of Non-Metallic Materials3.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 stain,contactdiscoloration of a product by anothermaterial or product in the area of direct contact.3.1.1.1 DiscussionA test for direct surface discolorationof rubber is covered by Test Method D1148.3.1.2 stain,diffusiondiscoloration of a light colored ve-neer or coating,caused by the diffusion of staining materialsfrom the rubber through the veneer or coating.3.1.2.1 DiscussionThe veneer or coating is in direct inti-mate contact with the underlying rubber.3.1.3 stain,migrationdiscoloration,caused by constitu-ents of a rubber,that occurs on any portion of the surface ofany object in the proximity of or adjacent to but not in directcontact with the rubber causing the stain.4.Summary of Test Methods4.1 The test methods are as follows:4.1.1 Method AContact Stain.4.1.2 Method BMigration Stain.4.1.3 Method CDiffusion Stain.4.2 Method ASpecimens to be tested for contact stainingare sandwiched between two metal panels.The metal panelsare furnished with a desired light colored organic finish,whichis in contact with the rubber.The assembly is exposed toelevated temperatures for a specified length of time and thespecimens are then removed from the metal.The degree ofstaining of the surface that was in contact with the rubber israted against a reference standard and a control panel(a metalplate without rubber)which are simultaneously tested with thespecimen.4.3 Method BSpecimens to be tested for migration stain-ing are placed on a metal plate with a desired light coloredorganic finish,and exposed to either fluorescent UVA-340lamps or filtered xenon arc radiation for a specified period oftime.The degree of staining beyond the area that was in contactwith the specimens is then rated against a reference standard1These test methods are under the jurisdiction of ASTM Committee D11 onRubber and are the direct responsibility of Subcommittee D11.15 on DegradationTests.Current edition approved May 1,2014.Published May 2014.Originallyapproved in 1947.Last previous edition approved in 2006 as D925 062.DOI:10.1520/D0925-14.2For 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 and a control panel(a metal plate without rubber)which aresimultaneously tested with the specimen.4.4 Method CDiffusion staining is tested on specimensprovided with a light colored rubber veneer or organic coating,deposited from organic solvent or water base.The specimensare exposed to either fluorescent UVA-340 lamps or filteredxenon arc radiation,with their veneer or coated side up,for aspecified period of time.Any staining of the light coloredveneer or organic coating is considered diffusion staining andrated against a reference standard and a control sample o