1、Designation: D 5145 09Standard Test Methods forNonvolatile and Pigment Content of Electrocoat Baths1This standard is issued under the fixed designation D 5145; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisi
2、on. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 These test methods cover the characterization of elec-trocoat baths through the determination of nonvolatile contentof inorganic
3、 pigment content.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.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
4、to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 1193 Specification for Reagent WaterD 2832 Guide for Determining Volatile and NonvolatileContent of Paint and Related CoatingsE 1
5、80 Practice for Determining the Precision of ASTMMethods for Analysis and Testing of Industrial and Spe-cialty Chemicals3. Summary of Test Method3.1 Two specimens are accurately weighed into aluminumweighing dishes. The dishes are placed in an oven at 110C for1 h, reweighed to obtain the nonvolatile
6、 matter content and, ifrequired, placed in a muffle furnace at 500C for2handweighed a third time to obtain the inorganic pigment content.4. Significance and Use4.1 The nonvolatile content and pigment content are mea-sures of total solids and inorganic pigment solids, respectively,in electrocoat pain
7、ts. In addition to production quality control,these properties are important in maintaining electrocoat bathsin the optimum range.4.2 Other test methods for determining nonvolatile contentof paint and paint related materials are described in GuideD 2832.5. Apparatus5.1 Analytical Balance with a sens
8、itivity of 0.1 mg.5.2 Aluminum Weighing Dishes, 57 mm in diameter and 17mm deep. These commercial dishes may contain a lubricantused during their manufacture. This should be removed byheating the aluminum dishes on a hot plate at 300C untilvapors are no longer visible. Store the dishes in a desiccat
9、oruntil needed.5.3 Syringes, 5-mL, disposable variety.5.4 Oven circulating, maintained at 110 6 2C.5.5 Muffle Furnace, maintained at 500 6 15C.6. Reagents6.1 Purity of WaterReferences to water shall be under-stood to mean water conforming to Type II of SpecificationD 1193.7. Sampling and Sample Prep
10、aration7.1 Obtain the sample while the electrocoat bath is underproper circulation so a uniform sample is obtained. In the caseof a ultrafiltrate sample, the material should be thoroughlymixed or stirred prior to drawing the sample, thereby ensuringuniformity.7.2 After sampling, prior to removing th
11、e test specimen, it ismandatory the sample be shaken or stirred until it is homoge-neous and free of any settled material. This is particularlyimportant if there is a delay between sampling the bath andperforming this test procedure. The absence of settled materialshould be ascertained visually or b
12、y inserting a spatula andscraping the bottom of the container. Continue to shake or stirthe sample until specimens are taken for measurement. ThisPoint is Very Important.NONVOLATILE CONTENT8. Procedure8.1 Weigh two aluminum dishes separately, each to 0.1 mgand record as W1.1These test methods are un
13、der the jurisdiction of ASTM Committee D01 onPaint and Related Coatings, Materials, and Applications and are the directresponsibility of Subcommittee D01.21 on Chemical Analysis of Paints and PaintMaterials.Current edition approved Feb. 1, 2009. Published March 2009. Originallyapproved in 1990. Last
14、 previous edition approved in 2003 as D 5145 - 03.2For 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.1*A Summary
15、 of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.8.2 Using a syringe, withdraw 1.0 to 1.5 mL of the wellmixed sample, then quickly weigh the syringe to 0.1 mg,recording this weigh
16、t as W2. Transfer the entire contents of thesyringe into the aluminum dish. Reweigh the empty syringe to0.1 mg and record as W3. In the case of ultrafiltrate clear liquidsor of low solids paints, increase the specimen size to 5 mL andpreheat at 60C for 2 h. Duplicate this step with the secondaluminu
17、m dish (8.1).8.3 Add a few millilitres of water to the specimen in thealuminum dishes prior to placing them in the oven. Thisfacilitates uniform spreading of the material. Place the dishesin the 110C oven for 1 h.8.4 Remove the dishes from the oven and allow to cool toroom temperature in a desiccato
18、r. Reweigh them to 0.1 mg andrecord the weights as W4.8.5 Retain the dishes for measurement of inorganic pigmentcontent as detailed in a following section of these test methods.9. Calculation9.1 Calculate the percent nonvolatile content as follows:% NV 5W42 W1W22 W33 100 (1)where:W1= weight of empty
19、 aluminum dish, g,W2= weight of syringe filled with sample, g,W3= weight of empty syringe, g, andW4= weight of dish and contents after1hat110C, g.10. Precision and Bias10.1 Precision is based on an interlaboratory study in whichthe operators in each of ten laboratories analyzed in duplicateon 2 days
20、, four different electrocoat-bath samples with non-volatile contents ranging from 0.30 to 25.2 %. The results wereanalyzed statistically in accordance with Practice E 180. Theintralaboratory coefficient of variance was 1.6 % at 40 df andthe interlaboratory coefficient of variation was 2.3 % at 36 df
21、.Based on these coefficients, the following criteria should beused for judging the acceptability of results at the 95 %confidence level.10.1.1 Repeatability: Two results, each the mean of dupli-cate determinations obtained by the same operator on differentdays, should be considered suspect if they d
22、iffer by more than4.6 % relative.10.1.2 Reproducibility: Two results, each the mean of du-plicate determinations obtained by operators in different labo-ratories, should be considered suspect if they differ by morethan 6.7 % relative.10.2 Bias cannot be determined because there are no ac-cepted stan
23、dards for nonvolatile content of electrocoat baths.INORGANIC PIGMENT CONTENT11. Procedure11.1 Place the weighing dishes used for the nonvolatilecontent determination in the muffle furnace at 500C for 2 h.11.2 After 2 h, remove the dishes from the muffle furnace,transfer them to a desiccator and allo
24、w to cool to roomtemperature. After cooling, remove dishes and weigh to 0.1mg, recording these weights at W5.NOTE 1If an organic char is still present in the aluminum dish after 2h in the muffle furnace, continue heating in the furnace until no char ispresent.12. Calculation12.1 Calculate the percen
25、t inorganic pigment as follows:% Inorganic Pigment EC Bath!5W52 W1W22 W33 100 (2)where:W1= weight of empty aluminum dish, g,W2= weight of syringe filled with sample, g,W3= weight of empty syringe, g, andW5= weight of aluminum dish and contents after heatingin muffle furnace, g.13. Precision and Bias
26、13.1 Precision estimates are based on an interlaboratorystudy in which the operators in ten different laboratoriesanalyzed in duplicate on 2 days, four electrocoat bath materialscontaining inorganic pigment content ranging from 0.17 to4.52 weight %. The results were analyzed statistically inaccordan
27、ce with Practice E 180. The intralaboratory coefficientof variation was 2.2 % relative at 40 df and the interlaboratorycoefficient of variation was 10.8 % at 36 df. Based on thesecoefficients, the following criteria should be used for judgingthe acceptability of results at the 95 % confidence level:
28、13.1.1 Repeatability: Two results, each the mean of dupli-cate determinations, obtained by the same operator on differentdays, should be considered suspect if they differ by more than6.3 % relative.13.1.2 Reproducibility: Two results, each the mean of du-plicate determinations, obtained by operators
29、 in different labo-ratories, should be considered suspect if they differ by morethan 31.1 % relative.13.2 Bias cannot be determined because there are no ac-cepted standards for inorganic pigment content of electrocoatbaths.14. Keywords14.1 electrocoat bath; muffle furnace; nonvolatile content;pigmen
30、t content; ultrafiltratesD5145092SUMMARY OF CHANGESCommittee D01 has identified the location of selected changes to this standard since the last issue(D 5145 - 03) that may impact the use of this standard. (Approved February 1, 2009.)(1) Editorial corrections made throughout.(2) 1.2 Added units of m
31、easurement statement.(3) 8.2 Added mL volume.(4) 10.1 Corrected coefficient of variance in interlaboratoryand intralaboratory studies.(5) 12.1 Corrected weight of aluminum dish and contents toW5.ASTM International takes no position respecting the validity of any patent rights asserted in connection
32、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 riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible te
33、chnical 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 International Headquarters. Your comments will receive careful consider
34、ation 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 Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr
35、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).D5145093
