1、Designation: D1978 91 (Reapproved 2018)Standard Guide forAnalysis of Electrocoat Bath Samples1This standard is issued under the fixed designation D1978; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A n
2、umber in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide covers the selection of test methods fordetermination of the important parameters that affect theperformance of electrocoatin
3、g paints.1.2 The test methods involved are D4370, D4399, D4584,and D5145.1.3 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 Rec
4、om-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D4370 Test Methods for Acid and Base MilliequivalentContent of Electrocoat BathD4399 Test Method for Measuring Electrical Conductivityof Electrocoat BathsD4584 T
5、est Method for Measuring Apparent pH of Electro-coat BathsD5145 Test Methods for Nonvolatile and Pigment Contentof Electrocoat Baths3. Significance and Use3.1 This guide indicates test procedures recommended forthe maintenance of acceptable performance of the paint in anelectrocoating bath. Several
6、critical parameters must be deter-mined throughout the operation of the bath. These parametersmust be adjusted when deviations from the norm occur.3.2 The test methods for electrocoat baths are unique, as theaqueous samples have a nonvolatile content between 8 and25 %. Constant agitation must be pre
7、sent when the samples aretaken and during the measurement of some of the parameters.4. Test Methods4.1 Acid and Base ContentTest Methods D4370 coversthe determination of acid and base milliequivalent content ofelectrocoat baths.4.2 Electrical ConductivityTest Method D4399 describesthe determination
8、of the electrical conductivity of electrocoatbaths.4.3 pH DeterminationTest Method D4584 describes themeasurement of the apparent pH of paints and ultrafiltrates ofelectrocoat baths.4.4 Nonvolatile and Pigment ContentTest Method D5145covers the determination of nonvolatile and inorganic pigmentconte
9、nt of electrocoat baths.5. Precision5.1 The referenced test methods have precision limits listed.Reference to the individual standards for precision statementsis recommended.6. Keywords6.1 electrical conductivity; electrocoat baths; nonvolatilecontent; pH; pigment content1This guide is under the jur
10、isdiction of ASTM Committee D01 on Paint andRelated Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.21 on Chemical Analysis of Paints and Paint Materials.Current edition approved June 1, 2018. Published June 2018. Originallyapproved in 1991. Last previous ed
11、ition approved in 2012 as D1978 91 (2012).DOI: 10.1520/D1978-91R18.2For 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 we
12、bsite.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of
13、 International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this sta
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16、which you may attend. If you feel that your comments 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 19428-295
17、9,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). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 91 (2018)2
