1、Designation:D 719 91(Reapproved 1999)Standard Test Methods forAnalysis of Diatomaceous Silica Pigment1This standard is issued under the fixed designation D 719;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision
2、.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 These test methods cover the analysis of diatomaceoussilica pigment.1.2 This standard does not purport to address the safetyconcerns,if
3、 any,associated with its use.It is the responsibilityof the user of this standard to establish appropriate safety andhealth practices and determine the applicability of regulatorylimitations prior to use.2.Referenced Documents2.1 ASTM Standards:D 185 Test Methods for Coarse Particles in Pigments,Pas
4、tes,and Paints2D 234 Specification for Raw Linseed Oil2D 235 Specification for Mineral Spirits(Petroleum Spirits)(Hydrocarbon Dry Cleaning Solvent)3D 280 Test Methods for Hygroscopic Moisture(and OtherMatter Volatile Under the Test Conditions)in Pigments2D 1208 Test Methods for Common Properties of
5、CertainPigments23.Significance and Use3.1 These test methods are used to determine the purity andsome physical properties of diatomaceous silica pigment.Theinformation is significant to pigment producers and coatingsmanufacture.MOISTURE AND OTHER VOLATILE MATTER4.Procedure4.1 Determine the moisture
6、and other volatile matter by TestMethods D 280.LOSS ON IGNITION5.Procedure5.1 Determine the loss on ignition in accordance with TestMethods D 1208.MATTER SOLUBLE IN HYDROCHLORIC ACID6.Procedure6.1 Transfer about 2 g(weighed to 0.1 mg)of the driedmaterial(Section 3)to a 150-mL flask or beaker.Add 45
7、mL ofhydrochloric acid(HCl,1+2)and boil for 5 min.Add 50 mLof water and boil for 5 min.Filter through a previously driedand weighed Gooch crucible.Wash the insoluble residue on thefilter with hot water until free of chlorides and then withmethanol.Dry the crucible and contents at 105 6 2C for 2 h.7.
8、Calculation7.1 Calculate the percent of matter soluble in HCl asfollows:Matter soluble in HCl,%5S 2 R!/S#3 100(1)where:S5 sample used,g,andR5 residue,g.VOLUME OF SETTLING IN PETROLEUMSPIRITS8.Procedure8.1 Transfer 3 g of the sample to a 100-mL,glass-stoppered,graduated cylinder.Add mineral spirits,c
9、onforming to Speci-fication D 235 until a total volume of 100 mL is obtained.Disperse the mixture by inverting the cylinder 50 times,andthen allow to stand for 1 h.Read the volume of the settledpigment.COLOR9.Standard Pigments9.1 Standard Extender Pigment.9.2 Standard Zinc Oxide.10.Procedure10.1 Car
10、efully weigh out the proportions of the standardextender pigment and standard zinc oxide mutually agreedupon,and rub up to a fairly stiff paste with a glass muller on aglass plate or stone slab with raw linseed oil conforming toSpecification D 234.Note the volume of oil required.Preparea similar pas
11、te with the sample,using the same weight ofpigment,volume of oil,and number of strokes of the glassmuller as used in the preparation of the paste of the standardpigments.Spread the pastes adjacently on a microscope slide,1These test methods are under the jurisdiction ofASTM Committee D-1 on Paintand
12、 Related Coatings,Materials,and Applications and are the direct responsibilityof Subcommittee D01.31 on Pigment Specifications.Current edition approved May 15,1991.Published July 1991.Originallypublished as D 719 43 T.Last previous edition D 719 86.2Annual Book of ASTM Standards,Vol 06.03.3Annual Bo
13、ok of ASTM Standards,Vol 06.04.1AMERICAN SOCIETY FOR TESTING AND MATERIALS100 Barr Harbor Dr.,West Conshohocken,PA 19428Reprinted from the Annual Book of ASTM Standards.Copyright ASTMdraw a scraper lightly across them so as to present them on aneven plane,and judge the color immediately.COARSE PARTI
14、CLES11.Procedure11.1 Determine the percent of coarse particles in accordancewith Test Methods D 185.12.Precision and Bias12.1 Precision and bias for these test methods have not beendetermined.13.Keywords13.1 diatomaceous silica pigment;analysis of;pigment;diatomaceous silicaThe American Society for
15、Testing and Materials takes no position respecting the validity of any patent rights asserted in connectionwith any item mentioned in this standard.Users of this standard are expressly advised that determination of the validity of any suchpatent rights,and the risk of infringement of such rights,are
16、 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 for revision of this standard or for additional standardsand should be addressed to ASTM Headquarters.Your comments will receive careful consideration at a meeting of the responsibletechnical committee,which you may attend.If you feel that your comments hav