1、Designation: D4890 06D4890 13Standard Test Methods forPolyurethane Raw Materials: Determination of Gardner andAPHA Color of Polyols1This standard is issued under the fixed designation D4890; the number immediately following the designation indicates the year oforiginal adoption or, in the case of re
2、vision, 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.1. Scope*1.1 These test methods measure visually the color of clear polyester and polyether liquids. They appl
3、y only to materials whosecolors have light-absorption characteristics similar to those of the standards. An alternative method is Test Method D1209 (seeNote 1).1.2 UnitsThe values stated in SI units are to be regarded as standard. No other units of measurement are included in thisstandard.1.3 This s
4、tandard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.NOTE 1Although Test Method
5、A of these test methods and ISO 4630-1:2004 differ in some details, data obtained using either are technicallyequivalent. Although this standard is equivalent to ISO 6271-1. Test Method B of these test methods and ISO 6271-1981 differ in some details, dataobtained using either are technically equiva
6、lent. this standard is equivalent to ISO 4630-1.2. Referenced Documents2.1 ASTM Standards:2D883 Terminology Relating to PlasticsD1193 Specification for Reagent WaterD1209 Test Method for Color of Clear Liquids (Platinum-Cobalt Scale)D5386 Test Method for Color of Liquids Using Tristimulus Colorimetr
7、yD6166 Test Method for Color of Pine Chemicals and Related Products (Instrumental Determination of Gardner Color)E177 Practice for Use of the Terms Precision and Bias in ASTM Test MethodsE308 Practice for Computing the Colors of Objects by Using the CIE SystemE691 Practice for Conducting an Interlab
8、oratory Study to Determine the Precision of a Test MethodE1164 Practice for Obtaining Spectrometric Data for Object-Color Evaluation2.2 ISO Standards:3ISO 4630-1:2004ISO 4630-1 Estimation Clear LiquidsEstimation of Colour by the Gardner Colour ScalePart 1: VisualMethodISO 4630-2:2004ISO 4630-2 Clear
9、 LiquidsEstimation of Colour by the Gardner Colour ScalePart 2: Spectroscopic MethodISO 6271-1981ISO 6271-1 Clear LiquidsEstimation of Color by the Platinum-Cobalt ScaleScalePart 1: Visual MethodISO 6271-2 Clear LiquidsEstimation of Color by the Platinum-Cobalt ScalePart 2: Spectroscopic Method3. Te
10、rminology3.1 For definitions of terms used in these test methods see Terminology D883.4. Summary of Test Method4.1 In Test Method A, the color of the material to be tested is compared to a series of color standards with defined chromicitycoordinates, prepared on one of three ways. The results are re
11、ported as the color standard, which best matches the sample.1 These test methods are under the jurisdiction of Committee D20 on Plastics and are the direct responsibility of Subcommittee D20.22 on Cellular Materials - Plasticsand Elastomers.Current edition approved Sept. 1, 2006April 1, 2013. Publis
12、hed September 2006April 2013. Originally approved in 1988. Last previous edition approved in 19982006 asD4890 - 98D4890 - 06.(2003). DOI: 10.1520/D4890-06.10.1520/D4890-13.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Ann
13、ual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036.10036, http:/www.ansi.org.This document is not an ASTM standard and is intended
14、only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current ve
15、rsionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14.2 InTest Method B, the color of the
16、 material to be tested is compared to a series of platinum-cobalt color standards, designatedby mg of Pt/mL of standard solution. The results are reported as the color standard, which best matches the sample (see Note 2).NOTE 2Color of liquids are also can be measured by visible spectroscopy and the
17、 results converted to any of several color scales. These results canbe are converted to the APHA scale by appropriate manipulations, as for example in Test Method D5386. and ISO 6271-2. These results are convertedto the Gardner scale by appropriate manipulations, as for example in Test Method ISO 46
18、30-2.5. Significance and Use5.1 These test methods are suitable for quality control, as specification tests, and for research. Color is an important propertyof urethane products.6. Sampling6.1 Polyesters and polyethers usually contain molecules covering an appreciable range of molecular weights. The
19、se have atendency to fractionate during solidification. Unless the material is a liquid or finely ground solid it is necessary to melt (using nohigher temperature than necessary) and mix the resin well before removing a sample for analysis. Many polyols are hygroscopicand care should be taken to pro
20、vide minimum exposure to atmospheric moisture during the sampling.7. Purity of Reagents7.1 Purity of ReagentsReagent-grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that allreagents shall conform to the specifications of the Committee on Analytical Reagents of
21、the American Chemical Society, wheresuch specifications are available.4 Other grades may be used, provided it is first ascertained that the reagent is of sufficiently highpurity to permit its use without lessening the accuracy of the determination.7.2 Purity of WaterUnless otherwise indicated, refer
22、ences to water shall be understood to mean reagent water as defined byType IV or better of Specification D1193.TEST METHOD AGARDNER COLOR8. Apparatus8.1 Gardner-Holdt Tubes, of clear glass, with closed, flat, even bottoms, and having the following approximate dimensions andmarkings:8.1.1 A uniform i
23、nternal length of 112 mm,8.1.2 A uniform internal diameter throughout the length of the tube of 10.75 mm, and8.1.3 An etched line around the outside of the tube 5 mm from the open end and a second etched line around the outside ofthe tube 13 mm from the open end.9. Reagents9.1 Cobalt Chloride Soluti
24、onPrepare a solution containing 1 part by weight of cobalt chloride (CoCl2 6H2O) to 3 parts ofHCl (1 to 17).9.2 Ferric Chloride SolutionPrepare a solution containing approximately 5 parts by weight of ferric chloride (FeCl3 6H2O)and 1.2 parts of HCl (1 to 17). Adjust to exact color equivalence to a
25、freshly prepared solution containing 3 g of K2Cr2O7 in 100mL of H2SO4 (sp gr 1.84).9.3 Hydrochloric Acid (1 to 17)Mix 1 volume of concentrated hydrochloric acid (HCl, sp gr 1.19) with 17 volumes of water.9.4 Hydrochloric Acid (0.1 N)Prepare 0.1 N HCl.9.5 Potassium Chloroplatinate (K(PtCl26Cr2O7).9.6
26、 Potassium Dichromate (K2Cr2O7).9.7 Sulfuric Acid (sp gr 1.84)Concentrated sulfuric acid (H2SO4).10. Gardner Color Reference Standards510.1 The primary standards for color shall consist of solutions defined by their spectral transmittance in 1-cm cell with parallelsides. The chromaticity coordinates
27、 of these solutions shall conform to those given in Table 1 when determined on a 1-cm layerof the solution in accordance with Practice E1164 and Test MethodMethods E308 and D6166.4 Reagent Chemicals, American Chemical Society Specifications, American Chemical Society, Washington, DC. For suggestions
28、 on the testing of reagents not listed bythe American Chemical Society, see Analar Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia and NationalFormulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD.5 The sole source of supply of the
29、 glass color standards and color standard solutions known to the committee at this time is BYK-Gardner USA, 9104 Guilford Road,Columbia, MD 21046. If you are aware of alternative suppliers, please provide this information to ASTM International Headquarters. Your comments will receive carefulconsider
30、ation at a meeting of the responsible technical committee,1 which you may attend.D4890 13210.2 For comparison, permanent solutions of known color are more satisfactory. The approximate composition of solutionsgiving each of the 18 Gardner colors is also given in Table 1. The solutions shall be made
31、from K2PtCl6 in 0.1 N HCl, or, in thedarker colors, from stock solutions of FeCl3, CoCl2, and HCl (see 9.1, 9.2, and 9.3). Pre-prepared Gardner color standard solutionsare commonly available for purchase.10.3 Solutions If the solutions in 10.2 are unavailable, solutions of K2Cr2O7 (sp gr 1.84) may b
32、e are used as reference standards.The approximate composition of these standards is also given in Table 1. Each solution must be freshly made for the colorcomparison, using gentle heat, if necessary, to effect solution.10.4 Secondary reference standards may be obtained in the form of 18 colored glas
33、s disks, which are set into a pair of larger,plastic disks and the latter mounted to rotate in a housing for holding the sample tube and glass disk in close and fixed proximity.11. Procedure11.1 Fill the tube with sample, free of solid particles or air bubbles, so that the apparent upper edge of the
34、 liquid meniscus iseven with the lower etched line on the tube.11.2 Determine the color by comparison with the reference standard solutions prescribed in Table 1, by comparing the sampleand the standard in Gardner-Holdt viscosity tubes as described. Make the comparison at 25 6 5C by placing tubes cl
35、ose togetherand looking through them against a white background or by comparison to the standards in a color disk.TABLE 1 Gardner Reference Standard Color SolutionsGardner Color StandardNumberChromaticityCoordinatesAPotassiumChloroplatinate,g/1000 mL of 0.1N HClIron-Cobalt Solutions PotassiumDichrom
36、ate, g/100 mLSulfuric AcidBx y Ferric ChlorideSolution, mL Cobalt ChlorideSolution, mL Hydrochloric Acid, mL1 0.3190 0.3271 0.550 . . . . . . . . . 0.00392 0.3241 0.3344 0.865 . . . . . . . . . 0.00483 0.3315 0.3456 1.330 . . . . . . . . . 0.00714 0.3433 0.3632 2.080 . . . . . . . . . 0.01125 0.3578
37、 0.3820 3.035 . . . . . . . . . 0.02056 0.3750 0.4047 4.225 . . . . . . . . . 0.03227 0.4022 0.4360 6.400 . . . . . . . . . 0.03848 0.4179 0.4535 7.900 . . . . . . . . . 0.05159 0.4338 0.4648 . . . 3.8 3.0 93.2 0.078010 0.4490 0.4775 . . . 5.1 3.6 91.3 0.16411 0.4836 0.4805 . . . 7.5 5.3 87.2 0.2501
38、2 0.5084 0.4639 . . . 10.8 7.6 81.6 0.38013 0.5395 0.4451 . . . 16.6 10.0 73.4 0.57214 0.5654 0.4295 . . . 22.2 13.3 64.5 0.76315 0.5870 0.4112 . . . 29.4 17.6 53.0 1.04116 0.6060 0.3933 . . . 37.8 22.8 39.4 1.28017 0.6275 0.3725 . . . 51.3 25.6 23.1 2.22018 0.6475 0.3525 . . . 100.0 0.0 0.0 3.00TAB
39、LE 1 Gardner Reference Standard Color SolutionsGardner Color StandardNumberChromaticity CoordinatesA PotassiumChloroplatinate,g/1000 mL of 0.1N HClIron-Cobalt Solutions PotassiumDichromate, g/100 mLSulfuric AcidBY x y Ferric ChlorideSolution, mL Cobalt ChlorideSolution, mL Hydrochloric Acid, mL1 80
40、0.3177 0.3303 0.550 . . . . . . . . . 0.00392 79 0.3233 0.3352 0.865 . . . . . . . . . 0.00483 76 0.3329 0.3452 1.330 . . . . . . . . . 0.00714 75 0.3437 0.3644 2.080 . . . . . . . . . 0.01125 74 0.3558 0.3840 3.035 . . . . . . . . . 0.02056 71 0.3767 0.4061 4.225 . . . . . . . . . 0.03227 67 0.4044
41、 0.4352 6.400 . . . . . . . . . 0.03848 64 0.4207 0.4498 7.900 . . . . . . . . . 0.05159 61 0.4343 0.4640 . . . 3.8 3.0 93.2 0.078010 57 0.4503 0.4760 . . . 5.1 3.6 91.3 0.16411 45 0.4842 0.4818 . . . 7.5 5.3 87.2 0.25012 36 0.5077 0.4638 . . . 10.8 7.6 81.6 0.38013 30 0.5392 0.4458 . . . 16.6 10.0
42、73.4 0.57214 22 0.5646 0.4270 . . . 22.2 13.3 64.5 0.76315 16 0.5857 0.4089 . . . 29.4 17.6 53.0 1.04116 11 0.6047 0.3921 . . . 37.8 22.8 39.4 1.28017 6 0.6290 0.3701 . . . 51.3 25.6 23.1 2.22018 4 0.6477 0.3521 . . . 100.0 0.0 0.0 3.00A Chromaticity coordinates for CIE standard illuminant C and the
43、 CIE 1931 (2) standard observer.B The dichromate color standards have been found to be less reliable than chloroplatinate or iron-cobalt color standards. They are included in Table 1 for reference only.D4890 13312. Report12.1 Report the color of the sample in terms of the Gardner standard number tha
44、t is nearest to it in color. If the sample appearsexactly halfway between two standards, report the color number of the darker standard.13. Precision and Bias613.1 PrecisionTheAttempts to develop a precision and bias statement for precision of this test method have not beensuccessful. For this reaso
45、n, data on precision and bias cannot be given; however, the precision is expected to be equivalent to thatreported in ISO 4630-1:2004. Because this test method does not contain a numerical precision and bias statement, it shall not beused as a referee test method in case ofis based on an interlabora
46、tory study conducted in 2011. Six laboratories tested two differentpolyurethane materials. Every “test result” represents an individual determination. Each laboratory reported three replicate testresults for each material. Practice E691 dispute.Anyone wishing to participate in the development of pre
47、cision and bias data shouldcontact the Chairman, Subcommittee D20.22 (Section D20.22.01),ASTM, 100 Barr Harbor Drive,West Conshohocken, PA19428.was followed for the design and analysis of the data; the details are given in ASTM Research Report No. D20-1257.13.1.1 Repeatability Limit (r)Repeatability
48、TwoBased on ISO 4630-1:2004, it would be expected test results obtainedwithin one laboratory shall be judged not equivalent if they differ by more than the “rthat ” value for that material; “rtwo replicatetest results, run on the same day, using the same equipment, ” is the interval representing the
49、 critical difference between two testresults for the same material, obtained by the same analyst, should be considered to be different only if they differ by more thanone color number. operator using the same equipment on the same day in the same laboratory.13.1.1.1 Repeatability limits are listed in Table 2.13.1.2 Reproducibility Limit (R)Two test results shall be judged not equivalent if they differ by more than the “R” value forthat material; “R” is the interval representing the critical difference between two test results for the same material, ob
