1、Designation: D 5064 07Standard Practice forConducting a Patch Test to Assess Coating Compatibility1This standard is issued under the fixed designation D 5064; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisio
2、n. 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 practice covers the procedures for testing coatingcompatibility when maintenance of an in-place coating systemis being conte
3、mplated. It does not cover procedures forassessing the integrity of the existing coating to determine if itcan be repainted, nor does it establish the compatibility of themaintenance coating system with the substrate or corrosionproducts. The practice is intended for use in the field.NOTE 1Pass-Fail
4、 Criteria (for example, adhesion requirements) arenot established by this practice. These should be established by the user orspecifier with input from the supplier.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 s
5、tandard 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 practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.
6、1 ASTM Standards:2D16 Terminology for Paint, Related Coatings, Materials,and ApplicationsD 3359 Test Methods for Measuring Adhesion by Tape TestD 4138 Practices for Measurement of Dry Film Thicknessof Protective Coating Systems by Destructive, Cross-Sectioning MeansD 4414 Practice for Measurement of
7、 Wet Film Thickness byNotch GagesD 4541 Test Method for Pull-Off Strength of CoatingsUsing Portable Adhesion TestersD 6132 Test Method for Nondestructive Measurement ofDry Film Thickness ofApplied Organic Coatings Using anUltrasonic GageD 6677 Test Method for Evaluating Adhesion by KnifeD 7091 Pract
8、ice for Nondestructive Measurement of DryFilm Thickness of Nonmagnetic Coatings Applied toFerrous Metals and Nonmagnetic, Nonconductive Coat-ings Applied to Non-Ferrous MetalsD 7234 Test Method for Pull-Off Adhesion Strength ofCoatings on Concrete Using Portable Pull-Off AdhesionTesters3. Terminolog
9、y3.1 DefinitionsFor definitions of terms used in this prac-tice, refer to Terminology D16.4. Summary of Test Method4.1 The materials under test are applied to the previouslypainted surface after proper surface preparation. After theappropriate time has elapsed, the test patch is examined forvisual d
10、efects and adhesion is determined.5. Significance and Use5.1 In performing maintenance of a coating system, the newcoating being applied must be compatible with the existingcoating. While general guides exist which indicate compatibil-ity of different generic types of coatings, differences inmanufac
11、turers formulation and the condition of the in-placecoating may affect compatibility.6. Procedure6.1 Select test locations for evaluation that properly charac-terize differences in configuration of the structure and expo-sure; that is, vertical versus horizontal surfaces and shelteredversus unshelte
12、red exposure.Aminimum of three test locationswith one test patch in each is recommended.6.2 The size of each test patch will be determined by thesize and configuration of the test locations. Each test patchshall be as large as possible, with a minimum size of 1.0m2(10.8 ft2) recommended.6.3 Prepare
13、the surface of the test areas using the methodsspecified for the maintenance painting procedure (Note 2).Alternative methods of preparation may also be evaluated inseparate, adjacent tests.1This practice is under the jurisdiction of ASTM Committee D01 on Paint andRelated Coatings, Materials, and App
14、lications and is the direct responsibility ofSubcommittee D01.46 on Industrial Protective Coatings.Current edition approved July 1, 2007. Published July 2007. Originally approvedin 1990. Last previous edition approved in 2001 as D 5064 01.2For referenced ASTM standards, visit the ASTM website, www.a
15、stm.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 C700, West Conshohocken, PA 19428-2959, United States.NOTE 2T
16、his test method assesses compatibility with the existingcoating only and does not apply to areas where the substrate is exposed bythe methods of preparation.6.4 Measure the existing coating thickness in accordancewith Test Methods D 6132, D 4138, or Practice D 7091,asappropriate for the substrate.6.
17、5 Measure the ambient conditions and surface temperatureand assure the conditions are within the limits specified by thecoatings manufacturer for the product being tested.6.6 Apply the test coating to the thickness recommended forthe particular job. Use the application technique as intended foruse o
18、n the full-scale job. If agreed upon between the purchaserand the seller, the method of coating application may bedifferent from that used on the job, that is, brush application ofthe test patch even though spray application will be used on thejob. However, this can cause some error and is not gener
19、allyrecommended.6.7 Immediately after application, measure the wet-filmthickness in accordance with Practice D 4414. Make correc-tions to the application, if necessary, by either applying morematerial if the expected dry-film thickness is low or applyinganother test patch if the expected dry-film th
20、ickness is abovethe recommended maximum. Inspect each patch for applica-tion defects such as runs, sags, and holidays. If such defectscannot be corrected as a part of the initial application process,prepare a new test patch.6.8 After the coating has dried, measure the dry-film thick-ness in accordan
21、ce with Test Methods D 6132, D 4138,orD 7091.NOTE 3When using Test Method D 6132 or Practice D 7091, the dryfilm thickness is the difference in average thickness of the coating systemless the average thickness of the in-place coating.6.9 Allow the coating to cure or weather prior to testing.Cure dur
22、ations are defined as long term and short term.Long-term curing provides the most reliable assessment ofcompatibility. Short-term curing provides for more rapid evalu-ation of results, but may not reveal all potential compatibilityproblems.6.9.1 Long-Term CuringCuring for as long a time aspossible,
23、with a minimum of six months preferred. Curingshould span seasonal weather changes.6.9.2 Short-Term CuringCuring at the following mini-mum times based on average daily (24 h) temperatures:10C (50F) 21C (70F) 32C (90F)14 days 10 days 7 daysLonger minimum cure times are acceptable if manufacturerrequi
24、res longer minimum cure times.6.10 After curing, examine the total surface of each testpatch for wrinkling, blistering, mudcracking, checking, crack-ing, peeling, lifting, and disbonding. Measure or rate theadhesion in a minimum of five locations per test patch inaccordance with Test Methods D 3359
25、or D 6677. If agreedupon between the purchaser and the seller, adhesion testing inaccordance with Test Methods D 4541 or D 7234 may be used.6.11 Examine the test patches for the defects noted in 6.10on a regular schedule, discounting rust caused by previous testssuch as adhesion measurements and des
26、tructive film thicknessmeasurements.7. Report7.1 Report the following information:7.1.1 The identity of the structure tested, the location andsize of the test patches, the identity of the test coating, themethod and grade of surface preparation, and the method ofcoating application.7.1.2 For each te
27、st patch, the dry film thickness measure-ments and average of the in-place coating, the dry filmthickness measurements and average of the test coating, theelapsed time for each evaluation, the visual defects noticed,and the results of adhesion tests.8. Keywords8.1 coating; coating compatibility; coa
28、ting test patch; paint;paint compatibility; test patchASTM 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 the validity of any such patent r
29、ights, 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. Your comments are invited either f
30、or 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 comments have not received a fair heari
31、ng 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).D5064072
