1、Designation:C75687(Reapproved 2016)Standard Test Method forCleanability of Surface Finishes1This standard is issued under the fixed designation C756;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number i
2、n parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.INTRODUCTIONThis test provides a procedure to quantify the cleanability of acid-resistant porcelain enamel usinga fluorescent water-soluble soil in agent,a re
3、producible machine-wiping technique,and a means ofmeasuring the amount of residual soil by fluorescence.1.Scope1.1 This test method covers the numerical evaluation of theease or difficulty of cleaning soiled surface finishes.This testmethod is applicable to all surface finishes not affected bywater.
4、1.2 Values given in SI units are to be regarded as thestandard.Inch-pound units are provided for information only.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 safe
5、ty and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2C282 Test Method for Acid Resistance of Porcelain Enam-els(Citric Acid Spot Test)C614 Test Method for Alkali Resistance of Porcelain Enam-els3.Summary of Test Met
6、hod3.1 The test method consists of applying an exact amount ofa fluorescent water-soluble soiling agent to a specimen surfaceand then cleaning the surface with a reproducible machine-wiping technique.The soil remaining on the specimen afterwiping is extracted with a water solvent and the fluorescenc
7、e ofthe solution measured.A standard reference surface is treatedin a similar manner.The cleanability index of the surface undertest is expressed as the ratio of the fluorescence of the solutionsextracted from the test surface and from the standard referencesurface.Cleanability indexes greater than
8、1.0 indicate that thetest surface is more difficult to clean than the standardreference surface,while indexes less than 1.0 indicate that thetest surface is more easily cleanable than the standard ofcomparison.3.2 The soiling agent used consists of polyethylene glycol,a black dye,and a fluorescent t
9、racer,each of which is readilywater soluble.4.Significance and Use4.1 This test method was developed to guide the user inselecting a finish coating or material that is resistant to soilingin a particular application.4.2 The numerical values derived by this test methodenables the user to rank finish
10、coatings and materials in regardto soil retention or ease of soil removal.5.Apparatus5.1 Motor-Driven Lapping Plate,203-mm(8-in.)diameter,speed 163 r/min.35.2 Automatic Polishing Unit,11-s cycle,adjustable to48-mm(178-in.)stroke.45.3 Hypodermic Syringe,glass,2-mL capacity,withoutneedle.5.4 Repeating
11、 Pipet,0.025 mL(25 l)capacity.5.5 Repeating Pipet,10-mL capacity.1This test method is under the jurisdiction ofASTM Committee B08 on Metallicand Inorganic Coatings and is the direct responsibility of Subcommittee B08.12 onMaterials for Porcelain Enamel and Ceramic-Metal Systems.Current edition appro
12、ved Nov.1,2016.Published November 2016.Originallyapproved in 1973.Last previous edition approved in 2011 as C756 87(2011)1.DOI:10.1520/C0756-87R16.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards vo
13、lume information,refer to the standards Document Summary page onthe ASTM website.3Suitable lapping plates are available from Buehler Ltd.,2120 Greenwood St.,Evanston,IL 60204,Struers,Inc.,20102 Progress Drive,Cleveland,OH,44136;orother Metallurgical Supply Sources.4An Olsen“S.M.”Automatic Polisher h
14、as been found suitable and is availableunder the code name OLPOL from Struers,Inc.,20102 Progress Drive,Cleveland,OH 44136.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.6 Desiccator approximately 254 mm(10 in.)diameter.5.7 Cleaning He
15、ad,brass,57 mm(214in.),with worm-driven hose clamp for attachment of cleaning tissues(Fig.1).5.8 Soiling Head,brass,25 mm(1 in.)diameter,with25-mm(1-in.)diameter facing of polytetrafluoroethylene at-tached with a water-proof household cement(Fig.1).5.9 Extraction Cell,fitted with a fluorosilicone O-
16、ring,size3.2 by 57 mm(18by 214in.)(Fig.2).55.10 Fluorometer,for measuring the fluorescence of solu-tions.65.11 0.9 Neutral Density Filter,50.8 by 50.8 mm(2 by 2 in.)glass mounted(transmission 12.5%).5.12 Beakers,borosilicate,100-mL capacity.6.Reagents and Materials6.1 Cleaning Tissues,approximately 127 by 229 mm(5 by9 in.).76.2 Potassium Carbonate.6.3 Polyethylene Glycol,400.6.4 Uranine,water-soluble,USP.86.5 Keco Acid Black,B(F101).96.6 Ethyl Alcohol.6.7 Mild Household Detergent,liquid.7.Test S