1、Designation: D7377 09 (Reapproved 2018)Standard Practice forEvaluating the Water Wash-Off Resistance of Traffic Paintsusing a Water Faucet1This standard is issued under the fixed designation D7377; the number immediately following the designation indicates the year oforiginal adoption or, in the cas
2、e 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 Atraffic paint film freshly applied to a roadway, air strip,or parking lot may be exposed t
3、o rain of varying intensitiesshortly after application. This practice was designed to deter-mine the relative water wash-off resistance of an applied trafficpaint film under controlled laboratory conditions using a waterfaucet to simulate a heavy rain. This laboratory practice canalso be used to com
4、pare conventional and fast-dry waterbornetraffic paints and the effects of binders and other components intraffic for their relative ability to withstand a heavy rain soonafter application.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for in
5、formationonly.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, health, and environmental practices and deter-mine the applicability of regulatory limitation
6、s prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization Techn
7、icalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D562 Test Method for Consistency of Paints MeasuringKrebs Unit (KU) Viscosity Using a Stormer-Type Viscom-eterD711 Test Method for No-Pick-Up Time of Traffic PaintD823 Practices for Producing Films of Uniform Thicknesso
8、f Paint, Coatings and Related Products on Test PanelsD1005 Test Method for Measurement of Dry-Film Thick-ness of Organic Coatings Using MicrometersD1212 Test Methods for Measurement of Wet Film Thick-ness of Organic CoatingsD4414 Practice for Measurement of Wet Film Thickness byNotch Gages3. Termino
9、logy3.1 Definitions:3.1.1 conventional waterborne traffc paint, nan aqueoustraffic paint that uses a conventional (non-fast-dry) latexbinder.3.1.1.1 DiscussionTypical no-pick-up dry times for con-ventional traffic paints by Test Method D711 are 20 to 45 min.These paints are often used for zone marki
10、ng of parking lotsand garages.3.1.2 durable fast-dry waterborne traffc paint, nan aque-ous traffic paint that uses a durable fast-dry latex binder.3.1.2.1 DiscussionAir or airless spray application onroadways is typically 0.65 mm (25 mils) wet or about 0.41 mm(16 mils) dry. The range of application
11、for durable waterbornepaints is 0.56 to 0.89 mm (22 to 35 mils) wet, but sometimesdurable paints are striped at standard line thickness. Typicalno-pick-up dry times by Test Method D711 for durable paintsapplied at standard line thickness are 5 to 8 min.3.1.3 effective water wash-off dry time, nthe t
12、raffic paintdry time required for no visible loss of coating when conduct-ing the water wash-off Standard Practice.3.1.4 fast-dry waterborne traffc paint, nan aqueous trafficpaint that uses a fast-dry traffic latex binder.3.1.4.1 DiscussionThese paints are sometimes also re-ferred to as fast-hardeni
13、ng since they still may contain asubstantial amount of moisture even though they feel dry.Typical no-pick-up dry times by Test Method D711 for fast-drytraffic paints are 10 min.3.1.5 standard line fast-dry waterborne traffc paint, nanaqueous traffic paint that uses a standard fast-dry latex binder.3
14、.1.5.1 DiscussionAir or airless spray application onroadways is typically 0.38 mm (15 mils) wet or about .223 mm1This practice is under the jurisdiction of ASTM Committee D01 on Paint andRelated Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.44 on Traffic C
15、oatings.Current edition approved Sept. 1, 2018. Published September 2018. Originallyapproved in 2007. Last previous edition approved in 2013 as D7377 09 (2013).DOI: 10.1520/D7377-09R18.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceast
16、m.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 StatesThis international standard was developed in accordance with in
17、ternationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1(9 mils) dry. Typical no-pick-up dry times fo
18、r standard linetraffic paints by Test Method D711 are 5 to 8 min.3.1.6 waterborne traffc paint, nan aqueous traffic paint(usually white or yellow) containing either a conventional orfast-dry latex binder.3.1.7 water wash-off resistance, nthe resistance of a trafficpaint line to partial or complete w
19、ash-out during a rain.4. Summary of Practice4.1 This standard practice involves preparing a series ofuniform thickness films of traffic paint on standard substrates.The films are allowed to dry over different time periods, andthen each paint film is subsequently tested with the water-wash-off test t
20、o determine the relative amount of coatingremaining at the end of the wash off period.5. Significance and Use5.1 After waterborne traffic paints are applied to a road,airstrip, or parking lot pavement, it is important that the paintfilms be sufficiently hardened, coalesced, or cured so they willnot
21、be removed by rain. This practice can be used to determinethe relative performance of binders and other componentswithin traffic paint for their effect on the water-wash offresistance of the coating. Some key elements of the coating thatmay affect water-wash-off performance are the quality and typeo
22、f latex binder, the dry time of the coating (often conducted byTest Method D711), pigment volume concentration (PVC), andthe relative water sensitivity of additives (for example, pigmentdispersants, and surfactants) in the coating.6. Apparatus and Equipment6.1 Paddle Type Viscometer, to measure visc
23、osity (in Krebsunits) of the traffic paint prior to application.6.2 Conditioning Room, to provide a constant standardenvironment of 23 6 2C (73.5 6 3.5F) and 50 6 5%relative humidity during film draw-downs and film drying.6.3 Conditioning Chamber, convenient to provide a constantstandard high humidi
24、ty environment of 23 6 2C (73.5 63.5F) and 90 6 3 % relative humidity during film draw-downsand film drying.6.4 Graduated Cylinder, to determine and adjust water flowrate from faucet.6.5 Humidity Gauge, to record relative humidity during thedrying period.6.6 Thermometers, to record the air and water
25、 temperatures.6.7 Spatula, to mix the paint prior to application.6.8 Glass Plates, for film draw-downs (see also option forcharts in 6.9).6.9 Draw-Down Chart, preferred option for film draw-downs. Black Scrub Test Panels are preferred and can be cut inhalf to give two test panels of 16.5 by 21.6 cm
26、(612 by 812 in.)size. Use of these charts instead of a glass plate allows for apermanent record of the test results.6.10 Film Applicator (15 cm (6 in.) width, to obtain 0.38mm (15 mil) wet thickness for standard traffic paints or 0.64mm (25 mil) wet thickness for durable traffic paints.6.11 Wet Film
27、 Gauge, to measure wet film thickness.6.12 Sink with combined hot and cold tap water faucet, toapply water stream onto test panel film during the waterwash-off testing.6.13 Lab Jack, to support the applied paint film, and tocontrol distance from the water nozzle.6.14 Timer, to time the film-drying a
28、nd the water wash-offperiods.6.15 Camera, to record the image of the panel after comple-tion of the test.7. Reagents7.1 Tap Water (Cold)applied to the film preferably with astandard nozzle, at controlled flow rate, controlled watertemperature, and constant distance from the test paint films.7.2 Acet
29、oneto clean glass plates prior to application (notneeded for draw-down charts since they are not reused).8. Procedure8.1 Paint Consistency:8.1.1 Determine the Krebs (KU) viscosity of the paint inaccordance with Test Method D562 using a paddle-typeviscometer as prescribed by Test Method D562. This de
30、termi-nation is optional but can be important since the dry time of thetraffic paint and water wash-off performance can be affected bythe paint viscosity.8.2 Application of Paint Films:8.2.1 For most consistent results and for testing undercontrolled conditions, it is recommended that paint film dra
31、w-downs be applied and allowed to dry in a controlledtemperature/controlled humidity (CTCH) room and/or in asmall conditioning chamber. The conditioning chamber isconvenient for high humidity testing. Standard conditions areshown in 6.2 and 6.3 respectively. Select the appropriatedraw-down bar to ob
32、tain the desired film thickness. A 0.38 mm(15 mil) wet film thickness is typical for standard-line trafficpaints, and a 0.64 mm (25 mil) wet film thickness is typical fordurable traffic paints. The film thickness determination shouldbe made in advance using Practice D823 by making a series ofdraw-do
33、wns with different applicator gaps and measuring thewet-film thickness of each using Test Method D1212 or TestMethod D4414. The actual wet film thickness is often muchlower than the indicated film applicator gap, for example, a 25mil gap may produce a 15 mil wet film thickness. Dry filmthickness can
34、 optionally be determined using Test MethodD1005. Clean a series of four glass plates with acetone, oroptionally use the preferred black draw-down charts for thefilm draw-downs.Allow the glass plates or charts to equilibrateto room temperature. Place about 10 ml of paint on the topcenter of the glas
35、s plate or draw-down chart and drag thedraw-down bar over the paint to produce a coating of uniformthickness. Immediately start a timer for each film drawn-down,and allow the films to dry undisturbed for the designated timeD7377 09 (2018)2period. Let one film dry for exactly 15 min., one for 30 min.
36、,one for 45 min., and one for 60 min. At the end of each drytime period, the water wash-off test is conducted on the paintfilm (see 8.3).8.3 Running Water Wash-Off Test:8.3.1 Select a sink deep enough for the wash-off test with aminimum of 40 cm (16 in.) distance from the faucet nozzle tobottom of s
37、ink. Place a lab jack in the sink and adjust the heightfrom the platform to the water faucet nozzle to keep thedistance constant. A distance of 30.5 cm (12 in.) is standard.This adjustment is important particularly if different sinks areused for the test. The drain should remain unobstructed so that
38、the sink does not fill with water during the test. Turn both thecold and hot water faucets on, and adjust the flow rate andwater temperature to 5.7 L/min (1.5 gal/min) and 25Crespectively. The flow rate can be determined using a graduatedcylinder to measure the volume over a fixed period of time. Th
39、estandard nozzle opening is 1.0 cm (0.40 in.). Any deviationfrom nozzle size, flow rate, or water temperature will givedifferent results and should be recorded if not standard. A flowregulator to control the water pressure may be helpful toprovide the correct predetermined flow rate.8.3.2 When the d
40、ry time is expired for a paint test film andwith the water flow/temperature already adjusted, place theglass panel or draw-down chart on the lab jack. Move thefaucet over the panel with the flow impinging on the center ofthe paint film and immediately start the timer. Watch the paintfilm and record
41、the time it takes for the water to break throughthe film. Allow the film to remain under the flow of water fora full 5 min. and then remove it. Note any blistering orsoftening of the remaining paint film. At the appropriate times,test the remaining film panels in similar fashion. A camera canbe used
42、 to obtain a picture for a comparative record of the testresults. The black chart substrates are particularly good forcontrast of the area washed off (black substrate will showthrough) with the remaining white or yellow paint films. Ifglass panels are used, they can be placed on a black substratefor
43、 similar contrast. For clean-up of glass plates, run the platesunder hot water to loosen the film and then scrape the paint offwith a razor blade scraper. The draw-down charts can simplybe discarded or retained for visual record.8.4 Relative Running Water Wash-Off Performance for aTest Series, see F
44、ig. 1.9. Report9.1 The following ideally should be recorded when usingthis practice:9.1.1 Viscosity of the paint in Krebs Units (KU),9.1.2 Drying conditions (temperature and humidity), wetfilm thickness, and dry times for each draw-down,9.1.3 Water temperature, distance to panel, and water flowrate,
45、 and9.1.4 Relative water wash-off performance comparisons fora given set of panels, that is, panels can be ranked from best toworst or pictures can be taken as a relative performance record,or both.10. Keywords10.1 rain resistance; traffic paint; water resistance; waterwash-off; water wash-outFIG. 1
46、 Illustrative Example of Water Wash-Off Performance for a Traffic Paint Test SeriesD7377 09 (2018)3ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that deter
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