1、Designation: D 2218 67 (Reapproved 2006)Standard Specification forMolybdate Orange Pigments1This standard is issued under the fixed designation D 2218; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A nu
2、mber in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) 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 specification covers the pigment known as molyb-da
3、te orange.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 The following hazard caveat applies to the test methodportion of this specification only. This standard does notpurport to address all of the safety concerns, if
4、 any, associatedwith its use. It is the responsibility of the user of this standardto establish appropriate safety and health practices anddetermine the applicability of regulatory limitations prior touse.2. Referenced Documents2.1 ASTM Standards:2D 126 Test Methods for Analysis of Yellow, Orange, a
5、ndGreen Pigments Containing Lead Chromate and Chro-mium Oxide GreenD 185 Test Methods for Coarse Particles in Pigments,Pastes, and PaintsD 235 Specification for Mineral Spirits (Petroleum Spirits)(Hydrocarbon Dry Cleaning Solvent)D 387 Test Method for Color and Strength of ChromaticPigments with a M
6、echanical MullerD 523 Test Method for Specular GlossD 600 Specification for Liquid Paint DriersD 822 Practice for Filtered Open-Flame Carbon-Arc Expo-sures of Paint and Related CoatingsD 1210 Test Method for Fineness of Dispersion of Pigment-Vehicle Systems by Hegman-Type GageE97 Test Method for Dir
7、ectional Reflectance Factor, 45-deg 0-deg, of Opaque Specimens by Broad-Band FilterReflectometry32.2 Federal Specification:TT-R-266 Resin, Alkyd; Solutions43. Composition and Properties3.1 Dry PigmentThe pigment shall be a product made bythe chemical coprecipitation of lead chromate and lead molyb-d
8、ate, with or without admixtures of other insoluble compoundsof lead or other materials used in manufacture to control certainproperties. The pigment shall conform to the requirements forchemical composition as prescribed in Table 1.3.2 The mass color and character of the tint formed by amixture with
9、 a white pigment shall be the same as, and thestrength shall be within mutually agreed upon limits of astandard acceptable to both the purchaser and the seller.3.3 When mutually agreed upon between the purchaser andthe seller as being essential to the end use of the pigment,resistance to loss of glo
10、ss, chalking, and color change shall betested as specified in 5.1.6 The exposed panel shall show nochalking, a loss of not more than 10 % of the original gloss,and a color change difference of not more than three units.4. Sampling4.1 Two samples shall be taken at random from differentpackages from e
11、ach 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 (10 000 lb), except that for shipments of less than10 000 lb two samples s
12、hall be taken. At the option of thepurchaser, the samples may be tested separately, or samplesfrom the same production unit may be blended in equalquantities to form a composite sample.1This specification is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials, and Ap
13、plications and is the direct responsibility ofSubcommittee D01.31 on Pigment Specifications.Current edition approved Nov. 1, 2006. Published November 2006. Originallyapproved in 1963. Last previous edition approved in 2002 as D 2218 - 67 (2002).2For referenced ASTM standards, visit the ASTM website,
14、 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.3Withdrawn.4Available from Standardization Documents Order Desk, DODSSP, Bldg. 4,Section D, 700 Robbins Ave., Philad
15、elphia, PA 19111-5098, http:/www.dodssp.daps.mil.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5. Test Methods5.1 Tests shall be conducted in accordance with the follow-ing ASTM test methods:5.1.1 Chemical Analysis of Lead Chromate
16、Proceed inaccordance with the Lead Chromate section of Test MethodsD 126. The alternative procedure is not applicable.5.1.2 Chemical Analysis of Lead Molybdate and TotalMolybdenumWeigh to 1 mg about 1-g sample of pigmentinto a 250-mL beaker. Add 20 mL of sulfuric acid (H2SO4,1+1) and heat to light f
17、umes. Cool the solution, dilute to 150mL, filter, and wash with water. To reduce chromate, addfreshly prepared sulfurous acid (H2SO3) until the solution turnsgreen, and then add several millilitres in excess. Boil thesolution until excess H2SO3is removed. Cool the solution to 5to 10C, and add 30 mL
18、of a 2 % solution of alphabenzoi-noxime in alcohol slowly, with stirring. Add sufficient brominewater to tint the solution a pale yellow, and then add a fewmore millilitres of the alphabenzoinoxime reagent. After 15min at 5 to 10C, filter the solution through very thin, mediumpaper. Then wash the so
19、lution with cold H2SO4(1+100) con-taining 25 to 50 mL of prepared alphabenzoinoxime reagentper litre. Place the precipitate in a platinum crucible, charcautiously, then ignite to constant weight at 500C, and weighas molybdenum oxide (MoO3). Calculate weight percent leadmolybdate (PbMoO4), M, as foll
20、ows:M 5 A 3 255!/S (1)where:A = weight of MoO3obtained, g, andS = specimen weight, g.5.1.3 Coarse ParticlesTest Methods D 185.5.1.4 Mass Color and Tinting StrengthTest MethodD 387.5.1.5 Moisture and Other Volatile MatterTest MethodsD 126.5.1.6 Resistance to Loss of Gloss, Chalking, and ColorChange:5
21、.1.6.1 Prepare a test enamel consisting of ingredientsconforming to the applicable specifications in the followingproportions:Ingredient Weight %Molybdate orange sample 29.51Alkyd resin solutionA61.72Mineral spiritsB8.37Lead naphthenateC0.25Cobalt naphthenateC0.15_Total 100.0AConforming to Type III
22、of U.S. Federal Specification TT-R-266.BSee Specification D 235.CSee Class B of Specification D 600.5.1.6.2 Give the enamel three passes through a moderatelytight roller mill setting to give a fineness of grind, as deter-mined following Test Method D 1210, of 1.5 mils (40 m) orless. Apply the enamel
23、 to duplicate flat metal panels by sprayor applicator to complete hiding, and allow to dry 72 h.Measure the gloss at 60 in accordance with Test MethodD 523. Measure the directional reflectance of the coating inaccordance with Test Method E97. Subject the coated panelsfor 168 h to accelerated weather
24、ing under the conditionsprescribed in Practice D 822. Examine the exposed coating forchalking. Wash the exposed panel under running water with athoroughly degreased lambs wool pad to remove scum or dirt.Wipe off the water with clean cheesecloth and dry the panel for2 h. Calculate the loss of gloss f
25、rom gloss measurements madebefore and after exposure. After exposure, determine thedirectional reflectance for each panel as described in TestMethod E97. Estimate the color change or lightness-differenceestimate (DL) as follows:DL 5 KY212 2 Y112! (2)where:Y1= luminous directional reflectance of the
26、panel mea-sured before exposure,Y2= reflectance measured after exposure, andK = 100 when the reflectances are expressed in decimalfractions or 10 if reflectances are expressed in per-cent.The color change for the coating shall be the mean obtainedfor the two panels.56. Keywords6.1 lead; molybdate ch
27、rome/molybdate; molybdate orange;pigment5The method of determining the lightness-difference estimate is described indetail in example 4, “Photoelectric Tristimulus Colorimetry with Three Filters,”Circular C429, NBSCA, Nat. Bureau Standards.TABLE 1 Requirements for Chemical Composition%Min MaxChromiu
28、m (calculated as PbCrO4) 70 .Molybdenum (calculated as PbMoO4) 8 .Total of all substances (including moisture andwater soluble compounds) other than insolublecompounds of lead. 12Moisture and other volatile matter . 1.5Coarse particles (total residue retained on a45-m (No. 325) sieve. 1.0Matter solu
29、ble in water . 1.0D 2218 67 (2006)2ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk
30、of infringement of such rights, are 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
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32、our views known to the ASTM Committee on Standards, 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).D 2218 67 (2006)3
