1、Designation: D 6736 08Standard Test Method forBurnish Resistance of Latex Paints1This standard is issued under the fixed designation D 6736; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in par
2、entheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method covers a procedure for measuring theresistance of latex paints to burnishing under dry conditions.1.2 The values stated in SI uni
3、ts 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 safety and health pra
4、ctices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:D 523 Test Method for Specular GlossD 2486 Test Methods for Scrub Resistance of Wall PaintsD 3924 Specification for Environment for Conditioning andTesting Paint, Varnish, Lacquer
5、, and Related Materials3. Terminology3.1 Definition:3.1.1 burnish resistance, nthe ability of a coating to resistan increase in its gloss (sheen) value after polishing or rubbing.4. Summary of Test Method4.1 Test paints are drawn down lengthwise on plastic panelsusing a 0.18-mm (7.0-mil) applicator
6、and allowed to air-dry forone week. Gloss readings are taken at three equally spacedpoints, lengthwise along the center of the panel. The panel isthen rubbed for 20 cycles on a scrub machine, after which glossreadings are again taken along the same path abraded by thescrub machine. The initial value
7、s are averaged and the finalvalues are averaged. The difference between the initial andfinal gloss readings, divided by the initial reading times 100 isa quantitative indication of the paints resistance to burnishing.Higher percentage increases denote poorer resistance andvice-versa.5. Significance
8、and Use5.1 Interior flat paints may become burnished in areas whereclothing or upholstered furniture rub against a wall. Thisrubbing may cause a smoother, glossier surface at the contactedarea, depending on the level or type of pigments in the paintand binder hardness. This method permits a more qua
9、ntitativeestimate of burnish resistance than those using manual rubbingtechniques.6. Apparatus6.1 Constant temperature/humidity room 23 6 2C (73.5 63.5F); 50 6 5 % relative humidity (standard conditions,Specification D 3924).6.2 Washability Machine (Scrub Machine), described in TestMethods D 2486.6.
10、2.1 Accessory Apparatus:6.2.1.1 Sandpaper Attachment, total weight 454 g.6.2.1.2 Glass Plate, measured to fit.6.2.1.3 Gasket Frame and Clamps.6.3 Large Vacuum Plate.6.4 Film Caster, having a 0.18-mm (7.0-mil) clearance.6.5 Glossmeter(s), capable of measuring 60 and 85 glossin accordance with Test Me
11、thod D 523.7. Materials7.1 Plastic Scrub Panels, 43.5 by 16.5 mm (17 by 6.5 in.),white or black.7.2 Cheesecloth, 4-ply, medium weave.28. Procedure8.1 Application and Evaluation of Test Paints:8.1.1 Attach a plastic panel to the vacuum plate and drawdown the test paint uniformly lengthwise, using the
12、 0.18-mm(7.0-mil) side of the applicator.8.1.2 Condition the panels for one week in the constanttemperature / humidity room or under other conditions agreedupon between the buyer and seller.8.1.3 Take three equally spaced gloss readings (Test MethodD 523) along the center length of the panel, making
13、 sure the1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.42 on Architectural Coatings.Current edition approved Feb. 1, 2008. Published March 2008. Originallyapproved in 200
14、1. Last previous edition approved in 2001 as D 6736 - 01.2Bleached cheesecloth, grade 20B, 24/20 (medium) weave was used in devel-oping this method.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken,
15、PA 19428-2959, United States.areas of the readings are within the travel path of the scrubmachine attachment. The resulting average of the three read-ings is used as the initial value prior to rubbing the panel. It issuggested that the gloss readings should be as follows:Semi-Gloss Paints 60Sheen Pa
16、ints 60 and 85Flat Paints 85In general, if the 60 reading drops below 20 units the 85reading should be recorded.8.1.4 Secure one layer of 4-ply cheesecloth lengthwise inthe sandpaper attachment of the scrub machine.8.1.5 Secure the panel on the scrub machine over the glassplate using the gasket and
17、clamps. Attach the sandpaperattachment to the scrub machine. Start the machine.8.1.6 Abrade the panel for 20 reciprocating cycles. Stop themachine.8.1.7 Remove the panel from the scrub machine and care-fully clean off any loose pigment from the panel. Re-read thepanel, again taking three equally spa
18、ced gloss readings alongpath of the burnished area. Average the values and use thisaverage as the final after burnishing value.9. Report9.1 Report the following information:9.1.1 The application clearance, if different than thosespecified in this test method.9.1.2 The drying time and conditions used
19、, if different thanthose specified in this test method.9.1.3 The number of cycles used in abrading the panels, ifdifferent than the number specified in this test method.9.1.4 The gloss angles used and the initial and final glossunits.9.1.5 The total weight the sandpaper attachment used in thetest.9.
20、1.6 The percent increase in gloss calculated by subtractingthe initial average reading from the final average reading,dividing by the initial reading, and multiplying by 100.10. Precision and Bias310.1 Interlaboratory Experimental Approach:10.1.1 The precision of this test method is based on aninter
21、laboratory study (research report is filed with ASTM) ofTest Method D 6736. Each of six laboratories tested theburnish resistance of latex paints. The percentage of glossincrease was determined for a total of five different paints, withthree replicates of the analysis being performed on eachsample.
22、Results from the interlaboratory study are summarizedin Table 1.10.1.2 Because different paint formulations vary in theirability to resist gloss change from burnishing, precision willalso vary. This interlaboratory study included samples fromfive different paint formulations each with different burn
23、ishingcharacteristics. The Initial 85 Gloss and the Mean ( x ) % 85Gloss Increase results for the samples are displayed in Table 1.10.2 Precision:10.2.1 RepeatabilityTwo test results obtained within onelaboratry shall be judged not equivalent if they differ by morethan the “r” value for that materia
24、l; “r” is the intervalrepresenting the critical difference between two test results forthe same material, obtained by the same operator using thesame equipment on the same day in the same laboratory.Repeatability for the five paints selected for this interlaboratorystudy ranged from 4 to 33 %.10.2.2
25、 ReproducibilityTwo test results should be judgednot equivalent if they differ by more than the “R” value for thatmaterial; “R” is the interval representing the difference be-tween two test results for the same material, obtained bydifferent operators using different equipment in different labo-rato
26、ries study ranged fro 5 to 36 %.10.2.3 Any judgment in accordance with statements 10.1.1or 10.1.2 would have an approximated 95 % probability ofbeing correct.10.3 BiasAt the time of the study there was no acceptedreference material suitable for determining the bias for this testmethod, therefore no
27、statement on bias can be made.11. Keywords11.1 abrasion resistance; burnish resistance; polishing3Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D011142.TABLE 1 Results From Interlaboratory StudyMaterialInitial85 Glossx(% 85 Glo
28、ssIncrease)rRPaint A 3.0 65.2 13.5 25.6Paint B 1.9 93.8 30.8 36.3Paint C 3.5 106.6 33.2 33.4Paint D 24.5 7.8 3.8 4.7Paint E 23.8 28.7 5.0 7.4D6736082SUMMARY OF CHANGESCommittee D01 has identified the location of selected changes to this standard since the last issue(D 6736 - 01) that may impact the
29、use of this standard. (Approved February 1, 2008.)(1) Added Precision and Bias section.ASTM 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 determination of
30、the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Y
31、our comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your commen
32、ts have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D6736083
