ASTM_D_763_-_06_2019.pdf

Designation:D76306(Reapproved 2019)Standard Specification forRaw and Burnt Umber Pigments1This standard is issued under the fixed designation D763;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 specification covers the pigments commerciallyknown as raw umber and burnt umber.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 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:2D50 Test Methods for ChemicalAnalysis of Yellow,Orange,Red,and Brown Pigments Containing Iron and Manga-neseD185 Test Methods for Coarse Particles in PigmentsD280 Test Methods for Hygroscopic Moisture(and OtherMatter Volatile Under the Test Conditions)in PigmentsD387 Test Method for Color and Strength of ChromaticPigments with a Mechanical MullerD1208 Test Methods for Common Properties of CertainPigments3.Composition and Properties3.1 Dry PigmentsThe pigments shall conform to thefollowing requirements:3.1.1 Raw UmberThe pigment shall be in a soft,dry formand shall be a hydrated oxide of iron(together with suchmanganese that is naturally associated with it)permeating asiliceous base and shall be free of admixtures of othersubstances except carbon pigments.The pigment shall conformto the requirements for composition prescribed in Table 1.3.1.2 Burnt UmberThe pigment shall be produced by thecalcination of raw umber and shall be free of admixtures ofother substances except carbon pigments.The pigment shallconform to the requirements for composition prescribed inTable 1.3.2 Paste in OilFor both raw and burnt umber,the paste inoil shall be made by thoroughly grinding the pigment withlinseed oil(with or without a small amount of volatile thinner)together with(where necessary)small amounts of wetting ordispersing agents to produce a paste or semipaste of satisfac-tory consistency.As received,it shall not be caked in thecontainer and shall break up readily in linseed oil to form asmooth paint of brushing consistency.It shall mix readily in allproportions,without curdling,with linseed oil,turpentine,orvolatile petroleum spirits,or any mixture of these substances.The paste shall conform to the following requirements:Pigment,min,%55Nonvolatile vehicle,min,%80Moisture by distillation,max,%2.0Coarse particles and skins(total residue retained on aNo.325(45-m sieve),max,%of dry pigment1.03.3 The mass color and character of the tint and the tintingstrength formed by a mixture with a white pigment shall bewithin mutually agreed upon limits of a standard acceptable toboth the purchaser and the seller.4.Sampling4.1 Two samples shall be taken at random from differentpackages from each lot,batch,days pack,or other unit ofproduction in a shipment.When no markings distinguishingbetween units of production appear,samples shall be takenfrom different packages in the ratio of two samples for each4540 kg or 10 000 lb,except that for shipments of less than10 000 lb,two samples shall be taken.At the option of thepurchaser,the samples may be tested separately or afterblending in equal quantities the samples from the sameproduction unit to form a composite sample.5.Test Methods5.1 Tests shall be conducted in accordance with the follow-ingASTM test methods.Test procedures not covered byASTMtest methods shall be mutually agreed upon by the purchaserand the seller.1This specification is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings,Materials,and Applications and is the direct responsibility ofSubcommittee D01.31 on Pigment Specifications.Current edition approved June 1,2019.Published June 2019.Originallyapproved in 1944.Last previous edition approved in 2012 as D763 06(2012).DOI:10.1520/D0763-06R19.2For 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.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 5.2 Chemical Analysis of Dry PigmentTest Methods D50.5.3 Moisture in