ASTM D6578 D6578M-2013 4678 Standard Practice for Determination of Graffiti Resistance《测定耐涂写性的标准实施规程》.pdf

1、Designation: D6578/D6578M 13Standard Practice forDetermination of Graffiti Resistance1This standard is issued under the fixed designation D6578/D6578M; the number immediately following the designation indicates theyear of original adoption or, in the case of revision, the year of last revision. A nu

2、mber in parentheses indicates the year of lastreapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers a basic method for evaluatinggraffiti resistance of coatings, and use of this practice toevaluate graffiti resistanc

3、e of coatings after outdoor or labora-tory accelerated exposure (either prior to or after graffiti isapplied). Graffiti resistance is based on how a defined set ofmarkings is removed by a defined set of cleaning agents.1.2 This practice also defines procedures (optional) toevaluate graffiti removal

4、after re-marking with subsequentre-cleaning. It does not address recoatability after a coating isno longer graffiti resistant.1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore

5、, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.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

6、 establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D523 Test Method for Specular GlossD4587 Practice for Fluorescent UV-Condensation Expo-sures of Paint and Related CoatingsD6695 Pract

7、ice for Xenon-Arc Exposures of Paint andRelated CoatingsE1347 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)GeometryG7 Practice for Atmospheric Environmental E

8、xposure Test-ing of Nonmetallic MaterialsG113 Terminology Relating to Natural and Artificial Weath-ering Tests of Nonmetallic Materials3. Terminology3.1 The definitions given in Terminology G113 are appli-cable to this practice.3.2 Definitions of Terms Specific to This Standard:3.2.1 cleaning agent,

9、 na material used to remove a mark-ing material from the coating surface.3.2.2 graffti resistance, nthe property of coatings to beresistant to the application of graffiti or exhibiting removal ofgraffiti without surface damage.3.2.3 marking material, na material that can be used toproduce graffiti.3

10、.2.4 recleanability, nthe ability of a coating to withstandmultiple cycles of marking with subsequent cleaning whilemaintaining its original characteristics.3.2.5 repellent, nthe property of coatings that preventsmaterials commonly used as graffiti markings, from forming acontinuous film upon applic

11、ation.4. Summary of Practice4.1 A series of materials typically used as graffiti markingsis applied to test panels of the surface being evaluated. Testspecimens may be exposed to outdoor or accelerated exposures(either before or after markings have been applied). The graffitimarkings are removed usi

12、ng a series of procedures that beginwith wiping with a dry cloth and end with cleaning the surfacewith an aggressive cleaner. After the best attempt has beenmade to remove markings, specimens are evaluated visually, oralternatively, by gloss and color change measurements todetermine cleanliness. The

13、 graffiti resistance is reported as acleanability level based on the mildest cleaning agent thatcompletely removes the graffiti marking without damaging thecoating.5. Significance and Use5.1 Graffiti on building and structures is an ongoing andincreasing problem. A number of coatings have been produ

14、ced1This practice is under the jurisdiction of ASTM Committee D01 on Paint andRelated Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.46 on Industrial Protective Coatings.Current edition approved Nov. 1, 2013. Published December 2013. Originallyapproved in 2

15、000. Last previous edition approved in 2008 as D6578 08. DOI:10.1520/D6578_D6578M-13.2For 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

16、page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1that are intended to be resistant to the application of a graffitimarking, or to provide a surface from which such markings canbe easily removed. The procedures d

17、escribed in this practiceprovide a standard set of conditions that can be used to evaluatethe graffiti resistance of a surface.5.2 Graffiti resistance determined according to this practiceis applicable to smooth surfaces. Graffiti resistance of the samecoatings applied to a rough or textured surface

18、 may be lower.5.3 Graffiti resistance of coatings determined after natural orlaboratory accelerated weathering, either before or aftermarking, conducted according to this practice, is considered ashaving more weight than graffiti resistance of the same coatingdetermined without weathering. Graffiti

19、resistance of coatingsdetermined after natural weathering should be considered ashaving more weight than graffiti resistance determined afterlaboratory accelerated weathering.6. Apparatus6.1 15 by 30 cm 6 by 12 in. panels representing theintended substrate.6.2 Lint-Free Cotton Cloth.6.3 Graffti Mark

20、ing Material:6.3.1 Solvent-Based Permanent Ink Marker, blue,6.3.2 Solvent-Based Acrylic Spray Paint, red,6.3.3 Solvent-Based Alkyd Spray Paint, red,6.3.4 Wax Crayon, blue or black,6.3.5 Ballpoint Ink,6.3.6 Water-based Ink Marker, black,6.3.7 Other marking materials based on mutual agreementbetween a

21、ll interested parties.6.4 15 by 30 cm 6 by 12 in. Template, with 25 by 25 mm1 by 1 in. square holes used to define area where graffitimarking material will be applied. The number of holes shouldbe equal to the number of marking materials, should be spreadapart from each other as much as possible, an

22、d should have a13 mm (0.5 in.) margin along the perimeter.6.5 Cleaning Agents:6.5.1 Dry, Lint-Free Cotton Cloth,6.5.2 Mild Detergent, as agreed upon between purchaserand seller (a solution of 5 % sodium phosphate isrecommended),6.5.3 Isopropyl Alcohol,6.5.4 Mineral Spirits,6.5.5 Xylene,6.5.6 Methyl

23、Ethyl Ketone (MEK).6.6 For Outdoor ExposuresOutdoor Exposure Rack,meeting the requirements of Practice G7 for open backedexposures.6.7 For Laboratory Accelerated Exposures6.7.1 Fluorescent UV Exposure Device, equipped with fluo-rescent UVA lamps with peak emission at 343 nm, andoperated in accordanc

24、e with Practice D4587.6.7.2 Xenon Arc Exposure Device, equipped with xenonarc(s) with daylight filter(s) and operated in accordance withPractice D6695, cycle 6.6.8 Proper Safety Equipment, as determined from the sol-vent Material Safety Data Sheets (MSDS), for example,solvent resistant gloves, and r

25、espirator.6.9 Glossmeter, 60, (for Evaluation Method B only).6.10 Colormeter, capable of D65, CIE LAB measurementsmeeting Test Method E1347 or Test Method E1349 (forEvaluation Method B only).7. Test Specimen7.1 Apply the coating to be evaluated for graffiti resistanceto the 15 by 30 cm 6 by 12 in. t

26、est panels according to themanufacturers instructions, following any relevant proceduresfor surface preparation prior to application.7.2 Prepare at least three specimens of each coating beingevaluated.7.3 Prepare also at least one file specimen that can be usedfor comparison to the unmarked or unexp

27、osed materials.7.4 Unless otherwise specified, allow the coated test speci-mens to cure for at least 24 h at room temperature beforecontinuing the test.NOTE 1It may be useful to prepare several sets of panels for eachcoating and allow the different sets to cure for different periods. Thepurpose woul

28、d be to determine the point at which optimum graffitiresistance occurs.7.5 Measure and record initial 60 gloss in accordance withTest Method D523 and color in accordance with Test MethodE1347 or Test Method E1349 (using a D65 illuminant, CIELAB calculations) on coated test specimens (for EvaluationM

29、ethod B only).7.6 Place the template described in 6.4 over the preparedtest panel and apply the entire complement of marking mate-rials prescribed in 6.3 so that each panel is marked with a 25 by25 mm 1 by 1 in. square of all graffiti materials (one markingmaterial for each space in the template).7.

30、6.1 Be careful not to cross-contaminate one markingmaterial with another. Remove template. Store the markedpanels at room temperature for at least 24 h before beginningto evaluate for removal.7.7 If the graffiti marking material does not uniformly coverthe test area of the panel, or resists adhering

31、 to it, the testsurface is considered “repellent.” In this case, beading of themarking material might occur. In this case, the appearance ofthe dried marking may be very irregular.8. Graffiti Removal Procedure8.1 Attempt to remove each marking material from thepanel with a cotton cloth alone, then b

32、y using a cotton cloththat has been wetted with the following cleaning agents,working through them in the order listed (increasing strength).(a) mild detergent(b) isopropyl alcohol (IPA)(c) mineral spirits(d) xlyene(e) methyl ethyl ketone (MEK)The area of the cotton cloth that is wetted should be we

33、llsaturated, but not dripping.D6578/D6578M 1328.2 Rub each marking vigorously until it is completelycleaned off, or until it is visually evident that no more of themark can be removed.8.3 Reposition and re-wet the cotton cloth between mark-ings as necessary, working through the entire panel with one

34、cleaning agent at a time.8.4 Use a different cotton cloth with each cleaning agent.NOTE 2As cleaning agents of increasing strength are used, some ofthe markings will probably be cleanable, whereas others will not. Exercisecare so that areas that have been cleaned are not contaminated withstronger ag

35、ents that are being used to clean other marks.9. Evaluation of Cleanability9.1 Method A, Visual:9.1.1 After the best attempt has been made to clean a mark,visually examine it and note any trace of the mark, that is, acolor change (shadow) or a loss of gloss.9.1.2 If the spot has returned to its orig

36、inal condition beforemarking, note which cleaning agent was used to remove themark. The mark will be considered to be cleanable with thisagent.9.2 Method B, Instrumentally:9.2.1 Retention of 60 GlossAfter the graffiti marking hasbeen removed, measure the 60 gloss. Determine the ratio ofthe average g

37、loss measured after the marking has been re-moved to the average gloss measured on the panels prior tomarking. The ratio shall be at least 0.90.9.2.2 Color ShiftAfter the graffiti marking has beenremoved, measure color in the area where the graffiti wasremoved. Calculate Delta E CIE LAB based on com

38、parison ofthe average color coordinates for the cleaned surface, and theaverage color coordinates for the surface prior to marking, orfor an unmarked area of the same specimen. For a graffitimarking to be considered as completely removed, the Delta Eshall be less than 2.9.2.3 Note the cleaning agent

39、. The mark will be consideredto be cleanable with this agent if the criteria in 9.2.1 and 9.2.2are met.10. Confirmation of Cleanability10.1 Repeat procedures in Sections 8 and 9 (using eitherMethod A or B for Section 9) on the other two replicates, onlybegin with the next weakest cleaning agent that

40、 removed eachmark from the first replicate of each system rather thanbeginning all removal attempts with a dry cotton cloth. If itdoes not remove the mark move to the next strongest agent (theone that removed the mark the previous time). Althoughunlikely, it may be that this does not remove the mark

41、. If thisoccurs, work up through the cleaning agents in order ofstrength. If a particular mark was not removed from the firstreplicate with MEK, begin with xylene on subsequent repli-cates.10.2 If it is not possible to completely remove the spotwithout adversely affecting the film, it is considered

42、to be notcleanable.10.3 Based upon the average of the results of the 3 replicatetrials, use the following rating scale for cleanability for eachcoating.Cleanable with a dry rag = 10Cleanable with detergent = 9Cleanable with IPA = 8Cleanable with mineral spirits = 7Cleanable with xylene = 6Cleanable

43、with MEK = 5Not cleanable, gloss loss = 4Not cleanable, slight shadow = 3Not cleanable, heavy shadow = 2Not cleanable, shadow and gloss loss = 111. Recleanability Procedure (Optional)11.1 In some cases, it is necessary to evaluate whether agraffiti resistant material will show the same level of clea

44、nabil-ity after it has been cleaned and remarked with graffiti.11.2 Re-mark the areas on the panels in the same locationsthat they were marked prior to cleaning with the same markingmaterials and allow the markings to cure for at least 24 hours.11.3 Attempt to remove the mark using procedures inSect

45、ions 8 and 9.11.4 If the marking is completely removed, repeat steps 11.2and 11.3 until the marking cannot be completely removedwithout damaging the coating. The recleanability is classifiedas the number of cycles performed until the marking is nolonger cleanable.12. Graffiti Removal From Panels Tha

46、t Have BeenSubjected To Outdoor Exposure12.1 Method ARemoval of freshly applied graffiti mark-ings from coatings that have been subjected to outdoorexposure:12.1.1 Prepare a set of specimens to be evaluated inaccordance with 7.1 7.4.12.1.2 Engrave or indent each of the panels so that they canbe iden

47、tified upon return from exposure.12.1.3 Unless otherwise specified, expose this set of panelsin accordance with Practice G7 on an open backed rack thatfaces the Equator and oriented at an angle of 45 to thehorizontal for 24 months. Note general atmospheric conditions,geographical location, and dates

48、 of exposure.NOTE 3Conditions will vary among geographic locations, whichcould produce different results. South Florida and Arizona desert arecommonly used locations.12.1.4 Remove from exposure and apply graffiti markings inaccordance with 7.5 7.7.NOTE 4The purchaser and seller shall agree upon whet

49、her or not thepanels should be washed (or to what extent the panels should be washed)before marking.12.1.5 Determine cleanablility of marked panels in accor-dance with Sections 810.12.1.6 Determine recleanability in accordance with Section11 (optional).12.2 Method BRemoval of graffiti markings after themarked panel has been subjected to outdoor exposure:12.2.1 Apply the coating and mark with materials in accor-dance with 7.1 7.7.12.2.2 Expose panels per 12.1.3.12.2.3 Determine cleanability of the marked, exposed pan-els in accordance with