ASTM_D_5724_-_16_2021.pdf

Designation:D572416(Reapproved 2021)Standard Specification forGouache Paints1This standard is issued under the fixed designation D5724;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 Thisspecificationestablishesrequirementsforcomposition,physical properties,performance,and labeling ofgouache paints.1.2 This specification covers pigments,vehicles,and addi-tives.Requirements are included for pigment identification,lightfastness,and consistency.1.3 Table 1 lists some pigments meeting the lightfastnessrequirements in this specification.In order to identify otherpigments that meet these requirements,instructions are givenfor test specimen preparation.Test methods for determiningrelative lightfastness are referenced.1.4 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.5 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 Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D185 Test Methods for Coarse Particles in PigmentsD279 Test Methods for Bleeding of PigmentsD476 Classification for Dry Pigmentary Titanium DioxideProductsD823 Practices for Producing Films of Uniform Thicknessof Paint,Coatings and Related Products on Test PanelsD1210 Test Method for Fineness of Dispersion of Pigment-Vehicle Systems by Hegman-Type GageD1535 Practice for Specifying Color by the Munsell SystemD4236 Practice for Labeling Art Materials for ChronicHealth HazardsD4303 Test Methods for Lightfastness of Colorants Used inArtists MaterialsE284 Terminology of Appearance2.2 Other Documents:Colour Index33.Terminology3.1 Definitions:3.1.1 colour index name,nconsists of the category(typeof dye or pigment),general hue,and an assigned number givento a colorant in the Colour Index3as an international identifi-cation system.3.1.1.1 DiscussionFor example,the Colour Index Nameof one phthalocyanine blue pigment is Pigment Blue 15(PB15).3.1.2 colour index number,na five-digit number given inthe Colour Index that describes the chemical constitution of acolorant.3.1.2.1 DiscussionFor example,the Colour Index Numberof one phthalocyanine blue pigment is 74160.3.2 Definitions of Terms Specific to This Standard:3.2.1 gouache paint,na pigment dispersion in a watersoluble gum/resin vehicle that dries water soluble and isformulated primarily for relatively opaque and matte applica-tions.3.3 Appearance terms used in this standard are defined inTerminology E284.4.Significance and Use4.1 This specification establishes quality requirements andprovides a basis for common understanding among producers,distributors,and users.4.2 It is not intended that all paints meeting the require-ments be identical nor of uniform excellence in all respects.Variations in manufacture,not covered by this specification,may cause some artists to prefer one brand over another,eitherof which may be acceptable under this specification.1This specification is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings,Materials,and Applications and is the direct responsibility ofSubcommittee D01.57 on Artist Paints and Related Materials.Current edition approved Nov.1,2021.Published November 2021.Originallyapproved in 1995.Last previous edition approved in 2016 as D5724 16.DOI:10.1520/D5724-16R21.2For 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.3The Society of Dyers and Colourists,Colour Index,3rd ed.,5 volumes andrevisions,Available from the American Association of Textile Chemists andColorists,P.O.Box 12215,Research Triangle Park,NC 27709.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 International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1?TABLE 1 Suitable Pigments ListNOTE1Underlined information in the table and lightfastness category shall be included on every label.KEYLightfastness Category:Lightfastness I Excellent LightfastnessLightfastness II Very Good LightfastnessAbbreviations used in Colour Index Names:PBPigment BluePBkPigment BlackPBrPigment BrownPGPigment GreenPOPigment OrangePRPigment RedPVPigmen