1、Designation: D 1475 98 (Reapproved 2008)Standard Test Method ForDensity of Liquid Coatings, Inks, and Related Products1This standard is issued under the fixed designation D 1475; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the
2、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 Department of Defense.1. Scope1.1 This test method covers the m
3、easurement of density ofpaints, inks, varnishes, lacquers, and components thereof, otherthan pigments, when in fluid form.1.2 For higher precision when working with nonpigmentedmaterials (drying oils, varnishes, resins and related materials),Test Method D 1963 can be used to determine specific gravi
4、tyand, thence, density.1.3 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly,1.4 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 st
5、andard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. A specific precau-tion statement is given in 8.1.1.1.2. Referenced Documents2.1 ASTM Standards:2D 1193 Specification for Reagent WaterD 1963 Test Method for Specific
6、Gravity of Drying Oils,Varnishes, Resins, and Related Materials at 25/25C3D 4052 Test Method for Density and Relative Density ofLiquids by Digital Density MeterE 180 Practice for Determining the Precision of ASTMMethods for Analysis and Testing of Industrial and Spe-cialty ChemicalsE 691 Practice fo
7、r Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3. Terminology3.1 Definitions:3.1.1 density, nthe mass of a unit volume of a material ata specified temperature. In this method, it is expressed as theweight in grams per millilitre, or as the weight in poundsavoirdupois
8、 of one U. S. gallon, of the liquid at the specifiedtemperature; in the absence of other temperature specification,25C is assumed.3.1.2 specific gravity (relative density), nthe ratio of themass of a unit volume of a material at a stated temperature tothe mass of the same volume of distilled water a
9、t the sametemperature.4. Summary of Test Method4.1 The accurately known absolute density of distilled waterat various temperatures (Table 1) is used to calibrate thevolume of a container. The weight of the paint liquid contentsof the same container at the standard temperature (25C) or atan agreed-up
10、on temperature is then determined and density ofthe contents calculated in terms of grams per millilitre, orpounds per gallon at the specified temperature.5. Significance and Use5.1 Density is weight per unit volume. It is a key property inthe identification, characterization, and quality control of
11、 awide range of materials. Density measurements in terms ofweight per gallon are commonly used to check paint quality. Ifthe density is not within specification, there is a good chancethat there was a mischarge or other serious problem.5.2 This test method is suitable for the determination ofdensity
12、 of paint and related products and components when inliquid form. It is particularly applicable when the fluid has toohigh a viscosity or when a component is too volatile for adensity balance determination.5.3 This test method provides for the maximum accuracyrequired for hiding power determinations
13、. It is equally suitablefor work in which less accuracy is required, by ignoring thedirections for recalibration and consideration of temperaturedifferentials, and using as the container a “weight-per-gallon”cup.5.4 Automatic equipment for measuring density is available(see Test Method D 4052) from
14、several manufacturers. Suchapparatus has been used for resins and latices as well as for oilsand solvents. Before such equipment is used for a givenproduct, results must be checked very carefully. Particularly1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coati
15、ngs, Materials, and Applications and is the direct responsibility ofSubcommittee D01.24 on Physical Properties of Liquid Paints hence, handling only with tongs and with handsprotected by clean, dry, absorbent material is recommended.NOTE 4Immediate and rapid weighing of the filled container isrecomm
16、ended here to minimize loss of weight due to evaporation of thewater through orifices, and from overflow subsequent to the first wipingafter attainment of temperature where this overflow is not retained by acap.8.1.5 Calculate the container volume as follows:V 5 N 2 M!/r (1)where:V = volume of conta
17、iner, mL,N = weight of container and water, g (8.1.4),M = weight of dry container, g (8.1.1), andr = absolute density of water at specified temperature,g/mL (see Table 1).8.1.6 Obtain the mean of at least three determinations.9. Procedure9.1 Repeat the steps in Section 8, substituting the sample for
18、the reagent water and a suitable nonresidual solvent for theacetone or alcohol (see Note 5). Record the weight of the filledcontainer, W, and the weight of the empty container, w,ingrams.NOTE 5Trapping of paint or ink liquids in ground glass or metal jointsis likely to result in high values of densi
19、ty that appear to increase with theTABLE 1 Absolute Density of Water, g/mLC Density15 0.99912716 0.99897117 0.99877218 0.99862319 0.99843320 0.99823121 0.99802022 0.99779823 0.99756624 0.99732425 0.99707226 0.99681127 0.99654028 0.99626029 0.99597230 0.995684D 1475 98 (2008)2viscosity and density of
20、 the material; such errors should be minimized byfirm seating of the joints.NOTE 6Trapping of air bubbles results in low values for density. Thetendency to trap air increases with increasing viscosity. Specimens shouldnot be tested if they contain bubbles or foam. Slow stirring, standing, orthe appl
21、ication of a vacuum may remove bubbles. If these do not work, adilution may be necessary (see Appendix X1).9.2 Calculate the density in grams per millilitre as follows:Dm5 W 2 w!/V (2)where:Dm= density, g/mL.9.3 Calculate the density in pounds per gallon as follows:D 5 W 2 w!K/V (3)where:D = density
22、, lb/gal,K = 8.3454 (Note 7), andV = volume of container, mL (see 8.1.6).NOTE 7The factor K, 8.3454, is calculated from volume-weightrelationship as follows:8.345404 = (2.54)3A3 (231.00)B/(453.59237)CA(2.54)3is the conversion factor for millilitres to cubic inches.B231.00 is the conversion factor fo
23、r cubic inches to gallons.C453.59237 is the conversion factor for grams to pounds.10. Report10.1 In reporting the density, state the test temperature to thenearest 0.1C, the units, and the value calculated to three places(for example, D = x.xxx lb/gal at 25C); state the mean, therange, and the numbe
24、r of replicate determinations.11. Precision and Bias11.1 PaintsThe precision estimates are based on an inter-laboratory study in which one operator in each of six differentlaboratories analyzed in duplicate on two different days fivesamples of paint ranging in density from 8.5 to 12.5 lb/gal. Theres
25、ults were analyzed statistically in accordance with PracticeE 180. The within-laboratory coefficient of variation was foundto be 0.20 % relative with 25 df and the between-laboratorycoefficient of variation was 0.61 % relative with 20 df. Basedon these coefficients, the following criteria should be
26、used forjudging the acceptability of results at the 95 % confidencelevel:11.1.1 RepeatabilityTwo results, each the mean of dupli-cate determinations, obtained by the same operator on differentdays should be considered suspect if they differ by more than0.6 % relative.11.1.2 ReproducibilityTwo result
27、s, each the mean of du-plicate determinations, obtained by operators in different labo-ratories should be considered suspect if they differ by morethan 1.8 % relative.11.2 InksA separate interlaboratory study of this testmethod was carried out for inks. In this study, one operator ineach of seven la
28、boratories made three determinations on fourdifferent paste ink samples. Paste inks were chosen becausetheir viscosities are high and they would be expected to providea difficult test for the method. The inks represented a densityrange of 8.4 to 8.9 lb/gal and exhibited viscosities ranging froma ver
29、y soft news black to a relatively heavy sheet-fed offset ink.The results were analyzed statistically in accordance withPractice E 691. The within-laboratory standard deviation was0.030 lb/gal and the pooled laboratory standard deviation was0.045 lb/gal. Based on these values, the following criterias
30、hould be used for judging the acceptability of results at the95 % confidence level:11.2.1 RepeatabilityTwo results obtained by the sameoperator should be considered suspect if they differ by morethan 0.084 lb/gal (1 %).11.2.2 ReproducibilityTwo results obtained by operatorsin different laboratories
31、should be considered suspect if theydiffer by more than 0.125 lb/gal (1.5 %).11.3 Bias (Paint and Inks)Since there is no acceptedreference material, bias cannot be determined.12. Keywords12.1 density; pycnometer; weight per gallon; weight pergallon cupAPPENDIXES(Nonmandatory Information)X1. DILUTING
32、 OF A MATERIAL TO IMPROVE AIR RELEASEX1.1 To reduce viscosity and improve air release, a knownweight of a material that traps air may be diluted with a knownweight of a solvent or another diluent of known density. Aftercareful blending to achieve homogeneity and release air, thedensity of the dilute
33、d material is measured by the techniquedescribed in this test method. The following equation may beused to calculate the density of the original material:Do5WoWo1 WdDd12WdDd2(X1.1)where:Do= density of original material,Dd1= density diluted measured in test,Dd2= density diluent,Wo= original weight, a
34、ndWd= diluent weight.D 1475 98 (2008)3X2. CENTRIFUGING OF MATERIAL TO REMOVE EXCESS AIRX2.1 To reduce the variation in the density method, air isremoved from the specimen by centrifuging the material,resulting in greater homogeneity between replicates. Thisgreatly improves reproducibility and repeat
35、ability and resultsin slightly higher density readings.X2.2 ApparatusX2.2.1 Centrifuge, capable of a maximum of 4000 r/min4,X2.2.2 Standard Density Cup,X2.2.3 Thermometer.X2.3 ProcedureX2.3.1 Fill the centrifuge tube to the top (approximately150 % of the density cup volume), adjust to the recommende
36、dtemperature of 25C 6 1. Place the tube in the centrifuge.X2.3.2 Turn on the centrifuge and set the speed control to2/3 power to attain a speed of 2700 to 3000 r/min.X2.3.3 Continue to run for 15 to 20 s, stop the centrifuge,applying the brake as needed.X2.3.4 Pour off the top foam layer.X2.3.5 Tran
37、sfer the specimen to a calibrated density cupand follow the procedure under Section 9.X2.4 Precision and BiasAn interlaboratory study in one company showed that thecentrifuge procedure resulted in a 2-fold improvement inrepeatability and reproducibility, as well as better accuracy.X2.4.1 Repeatabili
38、tyTwo results obtained by the sameoperator should be considered suspect if they differ by morethan 0.0054 g/mL (0.045 lb/gal).X2.4.2 ReproducibilityTwo results obtained by operatorsin different laboratories should be considered suspect if theydiffer by more than 0.0080 g/L (0.067 lb/gal).ASTM Intern
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40、heir 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 shoul
41、d be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Stand
42、ards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).4The centrifuge used in this study was a Dynac II.D 1475 98 (2008)4
