ASTM_D_5326_-_94a_2013.pdf

Designation:D532694a(Reapproved 2013)Standard Test Method forColor Development in Tinted Latex Paints1This standard is issued under the fixed designation D5326;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 parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers a procedure for measuring colordevelopment in tinted latex paints,for the purpose of deter-mining the efficiency of colorants,the tintability of base paintsand the potential for poor color uniformity of applied paintfilms.1.2 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.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 practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D16 Terminology for Paint,Related Coatings,Materials,andApplicationsD2244 Practice for Calculation of Color Tolerances andColor Differences from Instrumentally Measured ColorCoordinatesD3924 Specification for Environment for Conditioning andTesting Paint,Varnish,Lacquer,and Related MaterialsD3925 Practice for Sampling Liquid Paints and RelatedPigmented CoatingsE284 Terminology of AppearanceE1164 Practice for Obtaining Spectrometric Data for Object-Color EvaluationE1331 Test Method for Reflectance Factor and Color bySpectrophotometry Using Hemispherical GeometryE1345 Practice for Reducing the Effect of Variability ofColor Measurement by Use of Multiple MeasurementsE1347 Test Method for Color and Color-Difference Mea-surement by Tristimulus ColorimetryE1349 Test Method for Reflectance Factor and Color bySpectrophotometry Using Bidirectional(45:0 or 0:45)Geometry3.Terminology3.1 Definitions:3.1.1 color development,nthe extent to which the coloranthas achieved its full tinting potential,as evidenced by the colorchange or lack thereof,when the tinted paint is subjected tovery strong shear stress.3.1.2 tintability,nthe capability of a white or tint basepaint to accept various colorants,as evidenced by the colordevelopment in the mixture.3.1.2.1 DiscussionSometimes called“color acceptance.”3.2 See Terminology D16,E284,and the Paint/CoatingsDictionary3for definitions of other terms used in this testmethod.4.Summary of Test Method4.1 The test paint is applied by drawing it down on a stripedblack and white sealed chart,at a film thickness sufficient toobtain full hiding.4.2 A portion of the drawdown is subjected to strongshearing forces in a prescribed brushing procedure.4.3 The CIELAB color difference between the drawdownand sheared areas after drying,is reported as a measure ofdeficiency in the color development of the test paint.5.Significance and Use5.1 A colorant sometimes fails to disperse completely in abase paint due to poor compatibility,which can be the fault ofthe colorant,the paint,or both.This will result in poor colordevelopment,which is readily manifested by the commonprocedure of applying the paint with a doctor blade andsubjecting the drawdown to high shear stress by finger-rubbinga small area of the partially dry film.This tends to disperse1This 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 July 1,2013.Published July 2013.Originally approvedin 1992.Last previous edition approved in 2009 as D5326 94a(2009).DOI:10.1520/D5326-94AR13.2For 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 website.3Available from Federation of Societies for Coatings Technology(FSCT),492Norristown Rd.,Blue Bell,PA 19422-2350,http:/www.coatingstech.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 undeveloped colorant,if any,and produces a color variationbetween the unsheared and sheared areas of the paint film.Thevariation can be measured colorimetrically to give a numericalcolor difference value that is a measure of the color develop-ment of the original paint,the smaller the difference the betterthe color development and vice versa.Color difference valuesobtained by finger-rubbing were found to vary widely for thesame as well as among different operators.This test methodestablishes a controlled shear-stress procedure analogous to thefinger rub-up test,but with far better reproducibility.5.2 Poo