1、Designation: D 4213 08Standard Test Method forScrub Resistance of Paints by Abrasion Weight Loss1This standard is issued under the fixed designation D 4213; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision.
2、 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 covers an accelerated procedure fordetermining the resistance of paints to erosion caused byscrubbing. (Note: The
3、term wet abrasion is sometimes used forscrubbing, and wet abrasion resistance or scrubbability forscrub resistance.) Although scrub resistance tests are intendedprimarily for interior coatings, they are sometimes used withexterior coatings as an additional measure of film performance.1.2 The values
4、stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.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 safet
5、y and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 562 Test Method for Consistency of Paints MeasuringKrebs Unit (KU) Viscosity Using a Stormer-Type Viscom-eterD 1193 Specification for Reagent WaterD 1475 Test M
6、ethod For Density of Liquid Coatings, Inks,and Related ProductsD 2486 Test Methods for Scrub Resistance of Wall PaintsD 3450 Test Method for Washability Properties of InteriorArchitectural CoatingsD 3980 Practice for Interlaboratory Testing of Paint andRelated Materials3D 4828 Test Methods for Pract
7、ical Washability of OrganicCoatingsE70 Test Method for pH of Aqueous Solutions With theGlass ElectrodeE 180 Practice for Determining the Precision of ASTMMethods for Analysis and Testing of Industrial and Spe-cialty ChemicalsE 691 Practice for Conducting an Interlaboratory Study toDetermine the Prec
8、ision of a Test Method3. Summary of Test Method3.1 The material under test is applied to a black plastic scrubtest panel, and after drying one week, a section of the test panelis placed in a straight-line abrasion tester, adjacent to a similarsection of a standard calibration panel. The two sections
9、 arescrubbed simultaneously to produce essentially identical abra-sion experiences and the amount of erosion loss in each sectiondetermined from the panel weights before and after scrubbing.3.2 The scrub resistance on a dry-film basis is calculated asthe percent ratio of the weight loss of the calib
10、ration panel tothat of the test panel. From that value, scrub resistance iscalculated on the basis of both dry- and wet-film volume.4. Significance and Use4.1 Interior paint films often become soiled, especially neardoorways, windows, and play areas, and frequently need to becleaned by scrubbing. Th
11、is test method covers the determina-tion of the relative resistance of paints to erosion whenscrubbed.4.2 The precision of scrub resistance measurements inabsolute physical values, such as Test Methods D 2486 cycles-to-failure or this test method, microlitres per 100 cycles, is poordue to the relati
12、vely large effect of subtle and difficult-to-control variables in test conditions. The test method describedherein minimizes this problem by using a standard calibrationpanel as an integral part of each scrubbing operation andrelating its weight loss to that of the paint film under test toestablish
13、the latters scrub resistance.NOTE 1The numerical scrub resistance values obtained by this testmethod are of significance only in relation to the specific calibration panel1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials, and Applications and i
14、s the direct responsibility ofSubcommittee D01.42 on Architectural Coatings.Current edition approved Feb. 15, 2008. Published April 2008. Originallyapproved in 1983. Last previous edition approved in 2003 as D 4213 96 (2003).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcon
15、tact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.types with
16、 which the value is obtained. Thus, for example, a scrubresistance value of 83 with a Type X calibration panel would be reportedas 83X.4.3 Results obtained by this test method do not necessarilyrepresent the scrub resistance that might be determined if thetest film is allowed to dry before testing a
17、ppreciably longerthan the seven-day period specified herein.4.4 Results obtained by this test method do not necessarilyrelate to ease of soil or stain removal (also referred to as“cleanability” or “cleansability”). To test for those character-istics use Test Methods D 3450 and D 4828.5. Apparatus an
18、d Materials5.1 Straight-line Scrub Tester, set for 37 6 1 cycles perminute, having a minimum intrinsic stroke length of 255 mm(10 in.), counter for recording the number of scrub cycles, basepan, glass support plate, “Lilly” frame, and C-clamps to holddown the entire test assembly.5.2 Sponge Holder,
19、stainless steel construction, weight: 4506 10 g, approximate inside dimensions: 22 by 75 by 95 mm (78by3by334 in.).5.3 Polyurethane Sponges,4skin free, open-cell formation,density 0.032 to 0.040 g/cm3(2 to 2.5 lb/ft3), compression(25 % deflection) 4.8 kPa (0.7 psi), width and length 0.08 in. (2mm) l
20、arger than the sponge holder with which it is to be used,thickness such that when inserted into the sponge holder itprotrudes about 5 to 6 mm (0.25 in.) beyond the skirt (see Fig.1).5.4 Abrasive Pad,56-mm (14-in.) thick, cut to same size asthe sponge with which it is to be used.5.5 Film Caster, with
21、 horseshoe frame, clearance 175 m (7mils), film width approximately 135 mm (514 in.).5.6 Black Plastic Panels,6dimensions: 0.25 6 10 % by 165by 430 mm (0.01 6 10 % by 6.5 by 17 in.). Level and uniformdull black surface, impervious to and unaffected by water oraliphatic solvents, plasticizer-free, de
22、nsity 1.33 6 0.05 g/cm3.NOTE 2With dark colored paints use white panels. These should bethe same as the black except for color, and density: 1.41 6 0.05 g/cm3.5.7 Drawdown Plate, 6-mm (14-in.) thick, clear float glass,size adequate to be used as a base for drawdowns on thespecified scrub test panels
23、.5.8 Non-Abrasive Scrub Medium,7standard wetting liquid.Formula and preparation instructions are as follows:8, 9, 10FormulaParts by WeightWater, reagent, Specification D 1193, Type IV 89.6AHydroxyethyl cellulose82.0Detergent94.0Trisodium phosphate, anhydrous 4.0Acetic acid glacial 0.3BPreservative10
24、0.1100.0AVary to achieve a final consistency of 165 to 220 g (75 to 85 Krebs Units) witha Stormer viscometer in accordance with Test Method D 562.BVary to achieve a final pH from 9.5 to 10.0 in accordance with Test MethodE70.5.8.1 Slowly add the hydroxyethyl cellulose to the waterwhile stirring mech
25、anically. Stir until uniform and then slowlyadd 2 to 3 drops of 28 % ammonium hydroxide solution whilemixing, and continue mixing until the solution turns clear. Inthe order shown, add the other ingredients separately, stirringcontinuously. Be sure each item is uniformly dispersed beforeadding the n
26、ext one. Finally, add the preservative and adjust thepH with glacial acetic acid.NOTE 3When a referee test is made the medium should be freshlyprepared, or from a previously unopened container that is no more than1-year old.5.9 Analytical Balance With Windshield Enclosure, readingto 0.1 mg and accur
27、ate to 1 mg.5.10 Static Shield, a thin gage metal plate, size 110 by 165mm (414 by 612 in.), to be placed on the balance pan whenweighing. A satisfactory shield can be made from 0.175 to0.300 mm (7 to 12 mil) thick aluminum or tinplate.5.11 Oven, adjusted to 50 to 55C (120 to 130F).5.12 Calibration
28、Panels,11prepared in advance using paintsof suitable scrub resistance.NOTE 4The procedure for preparing calibration panels is the same asdescribed in 6.1 and 6.2 for regular test panels, except that the panels shallbe aged sufficiently before use to ensure that the effect of additional ageingon thei
29、r scrub resistance is negligible. A period of 6 months has beenfound adequate. Earlier use requires that in a given test series allcalibration panels be the same age.5.13 Pycnometer, for example, “weight-per-gallon” cup.6. Procedure6.1 Stir the test paint well by hand. (Do not shake). Strain ifneces
30、sary to remove skins and large particles. Clean the surface4Sponges, available from suppliers of scrub testers, cut to precise size for theirrespective holders.5Abrasive padScotch-Brite #7448 manufactured by 3M Company, 3M CenterBldg., St. Paul, MN 55144-1000 has been found satisfactory. Pads cut to
31、 the correctsize are available from suppliers of scrub testers.6Scrub Test PanelsBlack: Form P121-10N and White: Form P122-10N,available from The Leneta Co., 15 Whitney Rd., Mahwah, NJ 07430, were used inthe round-robin for this method. Other charts that are in compliance withrequirements stated in
32、5.6 may be used also.7Non-Abrasive Scrub MediumCatalog Item SC-1 available from The LenetaCompany is made in accordance with these requirements.8Hydroxyethyl cellulose having a molar substitution (MS) value from 1.8 to 2.5and a 2 % solution viscosity in the range of 4400 to 6500 cps.9Iso-octylphenox
33、y polyethoxyethanol detergent, such as Triton X-100 has beenfound satisfactory for this purpose.101,3,5-triethyl hexahydro-sym-triazine (Vancide TH), obtainable from R. T.Vanderbilt Co., 30 Winfield St., Norwalk, CT 06855, has been found satisfactory.11Calibration panels may be prepared by individua
34、l laboratories for internal useand for relating their results to those of associated laboratories. Suitably aged andstandardized calibration panels, having “poor,” “good,” and “very good” scrubresistance are available commercially from the Leneta Company. These areidentified as Type A, C, and D resp
35、ectively. The scrub resistance of Type A has beenfound to be approximately 35 % of Type C, and Type C approximately 50 % of TypeD.FIG. 1 Alignment of Panels for ScrubbingD4213082of the glass drawdown plate carefully, then dust the scrub testpanel making sure both sides are free of specks. Immediatel
36、yafter cleaning and dusting, place the panel on the drawdownplate (see 5.7) and tape or otherwise fasten it to the far end.Rub the panel against the plate with a lint-free cloth to developstatic attraction.6.2 Position the applicator at the fastened end of the panel,with its 7-mil (175-m) clearance
37、edge down, and evenlydistribute approximately 12 mL of test paint across the front ofthe blade. Draw the paint down at a uniform rate of speed. Therate of application should be fairly slow (3 to 4 s frombeginning to end) to prevent formation of pinholes or holidaysin the film. Air dry for one week i
38、n a horizontal position, in awell ventilated area kept at 23 6 2C (73 6 3.5F) and 50 610 % relative humidity.6.3 At the end of the specified drying time cut the panelaccurately in half with a paper cutter across the short dimen-sion, and set aside one of the half-sections for a second test.Take the
39、other half-section and make two subsections bycutting again, parallel to and 75 mm (3 in.) from the previouscut.6.4 Weigh the narrower subsection in grams to four decimalplaces. It is essential while weighing, for the static shield to reston the weighing pan and the panel to rest fully and flatly on
40、 thestatic shield.NOTE 5Weighing to four places is needed to ensure accuracy in thethird (viz., to the nearest mg).6.5 Place the two subsections in the machine, on the glasssupport plate, with the first-cut edge across the exact center lineof the scrub path, and the wider subsection positioned so th
41、atthe two second-cut edges are adjacent.6.6 Repeat procedures 6.3, 6.4 and 6.5 using the selectedcalibration panel (see Note 6), placing the first-cut edge of thecalibration panel adjacent to that of the test panel. See Fig. 1for the configuration of the panel subsections on the supportplate at this
42、 point.NOTE 6Use a calibration panel type similar in scrub resistance to thatof the test paint, unless a single standard is required for a widely varyinggroup of paints. In the latter case use calibration panels that can becharacterized as having “good” or intermediate scrub resistance.6.7 Place the
43、 Lilly frame (see 5.1) on the panel assemblyand clamp it down firmly to prevent any shift in the testassembly while scrubbing.6.8 Soak the sponge in tapwater and squeeze to a weight ofabout 20 g, then place it in the sponge holder making sure thesponge protrudes approximately 5 to 6 mm (14 in.) (see
44、 Fig. 2).6.9 Dampen the abrasive pad with tap water. Fill the 30-mLsyringe with scrub medium and distribute 15 mL evenly overits unprinted face.6.10 Place the unprinted face downward on the panelassembly and attach the sponge holder with sponge to thescrubbing machine, with the sponge resting square
45、ly on thepad.6.11 Distribute an additional 15 mL of scrub medium alongthe scrub path then start the machine. (No additional scrubmedium is required during the test).6.12 Scrub until either one of the two center sections hasbeen worn down sufficiently for the black substrate to becomefaintly visible
46、without actual break-through. In any case, do notexceed 800 cycles. During the first 200 cycles (if both films lastthat long) reverse the direction of the pad every 50 cycles, andabove 200 cycles, reverse after every 100, so that the pad is runabout the same number of cycles in each direction. Recor
47、d thenumber of scrub cycles at the stopping point.NOTE 7If the scrub medium obscures the abrasion path, making itdifficult to observe the show-thru status of the film, stop the machine atconvenient intervals and sweep the surface briefly with a 50-mm (2-in.)paint brush dampened with water.6.13 Remov
48、e and wash off the two center (narrow) subsec-tions with tap water. Press them between paper towels toabsorb free moisture, then oven-dry for 15 min at 50 to 55C(120 to 130F). After drying reweigh the two subsections todetermine their weight losses, recording them as Mtestand Mnin grams to four deci
49、mal places (“n” indicates identifying letterof the calibration panel type being used in the particular test,for example MA, MC, MD, etc.).6.14 Starting with 6.3, repeat the subsequent steps with theother halves of the test and calibration panels, to obtain twosets of weight loss values. For this second test use a fresh padand reverse the positions of the test and calibration panelsections in the machine.6.15 Determine the density (D) of the paint in g/mL, inaccordance with Test Method D 1475.6.16 Determine the nonvolatile fraction by weight (N)ofthepaint as
