1、Designation:D121005(Reapproved 2022)Standard Test Method forFineness of Dispersion of Pigment-Vehicle Systems byHegman-Type Gage1This standard is issued under the fixed designation D1210;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revisio
2、n,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.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 This test method covers
3、measurement of the degree ofdispersion(commonly referred to as“fineness of grind”)of thepigment in a pigment-vehicle system such as liquid coatingsand their intermediates.It may also be used to assess theinclusion of particulates by a cleanliness(or texture)rating.1.2 The values stated in SI units a
4、re to be regarded as thestandard.The values given in parentheses are for informationonly.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,health,and environment
5、al practices and deter-mine the applicability of regulatory limitations prior to use.1.4 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,Gui
6、des and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D1316 Test Method for Fineness of Grind of Printing InksBy the NPIRI Grindometer3.Summary of Test Method3.1 Tapered GageThe product is spread by means of
7、 ascraper in a machined tapered path.At some point in this path,particles or agglomerates,or both,will become visible.Adirectreading from the graduated scale is then made at the pointwhere the particles form a definite pattern.When the singlepath gage is used it is also possible to rate“cleanliness”
8、(see6.2).3.2 Stepped GageThe product is spread by means of ascraper on a stepped gage.There are 2 delimited sections onthis gage,each of 6.5 cm2(1 in.2)area,and of two differentdepths.A count is made of the particles deposited in the twodelimited areas,and cleanliness(texture)reading is deter-mined.
9、4.Significance and Use4.1 In making pigmented products,the pigment is usuallydispersed in a portion of the vehicle in some sort of mill.At thisstage,it is necessary to be able to judge if the pigmentagglomerates have been sufficiently broken up so as not tointerfere with the smoothness of the finish
10、ed coating film.Thistest method describes a way of making this judgment.5.Apparatus5.1 Tapered GageA hardened steel,stainless steel,orchrome-plated steel block(Fig.1)approximately 170 mm(6.7in.)in length,and 15 mm(0.6 in.)in thickness.The top surfaceof the block shall be ground smooth and planar and
11、 shallcontain one or two paths 127 mm(5 in.)in calibrated length.The path shall be tapered uniformly in depth lengthwise fromabout 4 mils(100 m)at 10 mm from one end to zero depth atthe other with intermediate calibrations in accordance with thedepth at those points.Preferred calibrations are Hegman
12、 unitsand micrometers(Note 1).Three path widths are covered bythis test method:5.1.1 Two Parallel Paths,each 12.5-mm(0.5-in.)wide andspaced 0.5-in.apart centered in a block 65-mm(2.5-in.)wide(see Fig.1).5.1.2 One Path,50 mm(2 in.)in width centered in a block90-mm(3.5-in.)wide(see Fig.1).5.1.3 One Pa
13、th,25 mm(1 in.)in width centered in a block65-mm(2.5-in.)wide(see Fig.1a).NOTE1Several arbitrary scales and modifications of the gage are usedby industry.In order that readings obtained with these arbitrary scales andmodifications can be reported in the preferred units,the approximate1This test meth
14、od is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings,Materials,and Applications and is the direct responsibility ofSubcommittee D01.24 on Physical Properties of Liquid Paints&Paint Materials.Current edition approved July 1,2022.Published July 2022.Originally approvedin 195
15、2.Last previous edition approved in 2014 as D1210 05(2014).DOI:10.1520/D1210-05R22.2For 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 on
16、the 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.1relationship of these scales to gage depth is shown in the f
