1、Designation: D 4213 96 (Reapproved 2003)Standard 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
2、 of last revision. 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 byscru
3、bbing. (Note: The 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 performan
4、ce.1.2 The values 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
5、appro-priate safety 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) Using a Stormer-Type ViscometerD 1193 Specification for Reagent WaterD 1475
6、 Test Method 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 MaterialsD 4828 Test Methods for
7、 Practical Washability of OrganicCoatingsE 70 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 t
8、he Precision 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 s
9、ections 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 th
10、e calibration 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 scrubb
11、ing. This 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
12、 relatively 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 toest
13、ablish the latters scrub resistance.NOTE 1The numerical scrub resistance values obtained by this testmethod are of significance only in relation to the specific calibration paneltypes with which the value is obtained. Thus, for example, a scrubresistance value of 83 with a Type X calibration panel w
14、ould 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 appreciably longerthan the seven-day period specified herein.1This test method is under the jurisdiction of ASTM
15、Committee D01 on Paintand Related Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.42 on Architectural Coatings.Current edition approved Dec. 1, 2003. Published December 2003. Originallyapproved in 1983. Last previous edition approved in 1996 as D 4213 96e1.2
16、For 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.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C
17、700, West Conshohocken, PA 19428-2959, United States.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 and Mater
18、ials5.1 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, stainle
19、ss steel construction, weight: 4506 10 g, approximate inside dimensions: 22 by 75 by 95 mm (78by3by334 in.).5.3 Polyurethane Sponges,3skin 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) larger t
20、han 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,46-mm (14-in.) thick, cut to same size asthe sponge with which it is to be used.5.5 Film Caster, with horse
21、shoe frame, clearance 175 m(7 mils), film width approximately 135 mm (514 in.).5.6 Black Plastic Panels,5dimensions: 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, density
22、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.5.8 N
23、on-Abrasive Scrub Medium,6standard wetting liquid.Formula and preparation instructions are as follows:7, 8, 9FormulaParts by WeightWater, reagent, Specification D 1193, Type IV 89.6AHydroxyethyl cellulose72.0Detergent84.0Trisodium phosphate, anhydrous 4.0Acetic acid glacial 0.3BPreservative90.1100.0
24、AVary 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 MethodE 70.5.8.1 Slowly add the hydroxyethyl cellulose to the waterwhile stirring mechanicall
25、y. 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 next one
26、. 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 accurate to
27、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 175 to 300mm (7 to 12 mil) thick aluminum or tinplate.5.11 Oven, adjusted to 50 to 55C (120 to 130F).5.12 Calibration Panels,10pr
28、epared 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 their scrub res
29、istance 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.3Sponges, available from suppliers of scrub testers, cut to precise size for theirrespectiv
30、e holders.4Abrasive padScotch-Brite #7448 manufactured by 3M Company, 3M CenterBldg., St. Paul, MN 55144-1000 has been found satisfactory. Pads cut to the correctsize are available from suppliers of scrub testers.5Scrub Test PanelsBlack: Form P121-10N and White: Form P122-10N,available from The Lene
31、ta Co., 15 Whitney Rd., Mahwah, NJ 07430, have beenfound satisfactory and are in compliance with requirements stated in 5.6.6Non-Abrasive Scrub MediumCatalog Item SC-1 available from The LenetaCompany is made in accordance with these requirements.7Hydroxyethyl cellulose having a molar substitution (
32、MS) value from 1.8 to 2.5and a 2 % solution viscosity in the range of 4400 to 6500 cps.8Iso-octylphenoxy polyethoxyethanol detergent, such as Triton X-100 has beenfound satisfactory for this purpose.91,3,5-triethyl hexahydro-sym-triazine (Vancide TH), obtainable from R. T.Vanderbilt Co., 30 Winfield
33、 St., Norwalk, CT 06855, has been found satisfactory.10Calibration panels may be prepared by individual laboratories for internal useand for relating their results to those of associated laboratories. Suitably aged andstandardized calibration panels, having “poor,” “good,” and “very good” scrubresis
34、tance are available commercially from the Leneta Company. These areidentified as Type A, C, and D respectively. 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 ScrubbingD 4213 96 (2003)26. Procedur
35、e6.1 Stir the test paint well by hand. (Do not shake). Strain ifnecessary to remove skins and large particles. Clean the surfaceof the glass drawdown plate carefully, then dust the scrub testpanel making sure both sides are free of specks. Immediatelyafter cleaning and dusting, place the panel on th
36、e 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 edge down, and evenlydistribute approximately 12 m
37、L 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 in a horizontal position, in awell ventilated area
38、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 other half-section and make two subsections bycutt
39、ing 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 thestatic shield.NOTE 5Weighing to four places is
40、 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 thatthe two second-cut edges are adjacent.6.6 Repeat
41、 procedures 6.3, 6.4 and 6.5 using the selectedcalibration panel (see Note 6 below), placing the first-cut edgeof the calibration panel adjacent to that of the test panel. SeeFig. 1 for the configuration of the panel subsections on thesupport plate at this point.NOTE 6Use a calibration panel type si
42、milar 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 Lilly frame (see 5.1) on the panel assembly
43、and 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 Fig. 2).6.9 Dampen the abrasive pad with ta
44、p 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 squarely on thepad.6.11 Distribute an additional 1
45、5 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 without actual break-through. In any case, d
46、o 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. Record thenumber of scrub cycles at the stopping
47、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 Remove and wash off the two center (narrow) subse
48、c-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 decimal places (“n” indicates identifying letter
49、of 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 follows:6.16.1 Sandwich 0.4 mL of paint (d
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