1、Designation:D713305 Designation: D7133 11Standard Test Method forPolyurethane Raw Materials: Instrumental Measurement ofTristimulus CIELAB Color and Yellowness Index of Liquids1This standard is issued under the fixed designation D7133; the number immediately following the designation indicates the y
2、ear oforiginal adoption or, in the case of revision, 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 This test method provides an instrumental method for
3、 measuring the CIELAB color and Yellowness Index (YI) of liquidpolyurethane raw materials. The CIELAB and YI results are derived from mathematical manipulation of CIE tristimulus valuesin accordance with Practices E308 and E313, respectively.1.2See Section 5 for cautions in using this test method.1.
4、31.2 This standard 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.NOTE1There is no
5、 equivalent ISO standard. 1There is no known ISO equivalent to this standard.2. Referenced Documents2.1 ASTM Standards:2D883 Terminology Relating to PlasticsD1193 Specification for Reagent WaterE180 Practice for Determining the Precision of ASTM Methods for Analysis and Testing of Industrial and Spe
6、cialty ChemicalsE284 Terminology of AppearanceE308 Practice for Computing the Colors of Objects by Using the CIE SystemE313 Practice for Calculating Yellowness and Whiteness Indices from Instrumentally Measured Color CoordinatesE691 Practice for Conducting an Interlaboratory Study to Determine the P
7、recision of a Test Method3. Terminology3.1 DefinitionsFor definitions of terms that appear in this test method, refer to Terminologies E284, D883, and theterminology section of Practice E308.4. Summary of Test Method4.1 The color of the total transmitted light is measured by a spectrophotometer in C
8、IE tristimulus values under CIE standardilluminant D65 and CIE 1964 supplementary standard observer commonly called the 10 standard observer. These values are thenconverted by the appropriate equations to the CIELAB color scale and the Yellowness Index. L*a*b* and YI values are reported.5. Significa
9、nce and Use5.1 CIELAB is a visual-based scale that can be used to specify color and set color tolerances for the polyurethane industry.5.2 Yellowness Index specifies the degree of departure of the sample from colorless towards yellow. This index is only suitablefor clear liquids with degrees of satu
10、ration in yellow (dominant transmission wavelength in the 570 to 580 nm range). It can beused to set tolerances for appropriate polyurethane raw materials.5.3 This test method does not include provisions for materials with fluorescence or visible haze (usually greater than 5 % haze).5.4 Before proce
11、eding with this test method, make reference to the specification of the material being tested. Any test specimenpreparation, conditioning, dimensions, or testing parameters or combination thereof, covered in the materials specification shall1This test method is under the jurisdiction of ASTM Committ
12、ee D20 on Plastics and is the direct responsibility of Subcommittee D20.22 on Cellular MaterialsPlasticsand Elastomers.Current edition approved Dec. 15, 2005. Published January 2006. DOI: 10.1520/D7133-05.on Cellular Materials - Plastics and Elastomers.Current edition approved Feb. 1, 2011. Publishe
13、d February 2011. Originally approved in 2005. Last previous edition approved in 2005 as D7133 - 05. DOI:10.1520/D713311.2For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refe
14、r to the standards Document Summary page on the ASTM website.1This document is not an ASTM standard and is intended 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 ch
15、anges accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100
16、Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.take precedence over those mentioned in this test method. If there are no material specifications, then the default conditions apply.6. Interferences6.1 This test method is to be used to compare samples only when they ar
17、e measured under the same conditions.6.1.1 The medium in the cuvette used during standardization of the instrument will have an effect on the measured results. Lightmineral oil is recommended, however, distilled water can be used as a substitute but a note of the substitution must be includedin any
18、report of the results.6.1.2 The temperature of the sample is also expected to affect the results obtained.7. Apparatus7.1 InstrumentA hemispherical geometry (integrating sphere) spectrophotometer capable of total transmission (TTRAN) CIEtristimulus measurement through a cuvette. TTRAN includes both
19、the regularly transmitted portion and the diffused portion of theincident light. The instrument must be capable of converting CIE XYZ tristimulus values to the CIELAB color scale as definedin Practice E308 using CIE D65 standard illuminant and 10 standard observer. The instrument must also be capabl
20、e of convertingCIE XYZ tristimulus values to the Yellowness Index value defined in Practice E313 using CIE D65 standard illuminant and 10standard observer. The instrument is to meet the manufacturers requirements for calibration. For highly transparent samples, suchas the polyols below,in Tables 1 a
21、nd 2, spectrophotometers or tristimulus colorimeters without a spherical geometry can be usedwith equivalent results.7.2 Sample CuvettesThe cuvette must have a 20 6 0.06 mm pathlength. The entrance and exit windows shall be parallel,colorless, clear and unaffected by the material being analyzed. The
22、 optical properties of the cuvette used during standardizationof the instrument and the cuvette used for measuring samples (if not the same cuvette) must be matched. This can be determinedby proving that the variation, if any, in the different cuvettes used do not affect the measured value of a stan
23、dard sample. Glassor plastic cuvettes can be used.8. Reagents8.1 Mineral OilColorless NF or FCC grade light mineral oil.TABLE 1 CIELAB Round Robin DataL* valuesStandard Material Viscosity Average SrASRBrCRDMineral OilPMDI A 200 mPa s(200 cP)44.93 0.05 0.76 0.15 2.13PMDI B 750 mPa s(750 cP)1.64 0.03
24、0.26 0.10 0.74Polyol A 475 mPa s(475 cP)99.88 0.03 0.14 0.07 0.40Polyol B 6500 mPa s(6500 cP)96.01 0.11 0.85 0.31 2.37a* valuesStandard Material Viscosity Average SrASRBrCRDMineral OilPMDI A 200 mPa s(200 cP)45.80 0.03 0.26 0.07 0.72PMDI B 750 mPa s(750 cP)9.17 0.12 1.01 0.33 2.82Polyol A 475 mPa s(
25、475 cP)0.13 0.00 0.02 0.01 0.07Polyol B 6500 mPa s( 6500 cP)1.82 0.03 0.26 0.07 0.72b* valuesStandard Material Viscosity Average SrASRBrCRDMineral OilPMDI A 200 mPa s(200 cP)72.88 0.09 4.72 0.25 13.22PMDI B 750 mPa s (750 cP) 2.37 0.08 0.44 0.23 1.23Polyol A 475 mPa s(475 cP)0.63 0.01 0.10 0.03 0.29
26、Polyol B 6500 mPa s( 6500 cP)12.32 0.06 1.33 0.16 3.74ASr= within laboratory standard deviation of individual replicates.BSR= between laboratories standard deviation of means of replicates.Cr = within laboratory critical interval between individual replicates (2.8 3 Sr)repeatability.DR = between lab
27、oratory critical interval between means of replicates (2.8 3 SR)reproducibility.D7133 1128.2 Distilled WaterColorless distilled water conforming to Type IV of Specification D1193.9. Sampling and Test Specs and Units9.1 Test samples are to be homogeneous and representative of the liquid being tested.
28、9.2 Do not touch the entrance and exit windows of the cuvette through which incident and transmitted light will pass exceptto clean them.9.3 The CIELAB values, L*, a*, and b*, have no units associated with them.9.4 The Yellowness Index value, YI, has no unit associated with it.9.5 Since organic isoc
29、yanates react with atmospheric moisture, take special precautions in sampling. Usual sampling methods,even when conducted rapidly, can cause contamination of the sample with insoluble urea. Therefore, blanket the sample with dryair or nitrogen at all times. (WarningMany diisocyanates are known or su
30、spected sensitizers. Over-exposure to diisocyanatescan lead to adverse health effects which include the development of occupational asthma and other respiratory, skin and eye effects.Engineering controls and/or personal protective equipment, including respiratory, skin and eye protection, are to be
31、used whenthere is a potential for over-exposure to diisocyanates. The product suppliers Material Data Safety Sheet (MSDS) provides moredetailed information about potential adverse health effects and other important safety and handling information.Always follow thespecific instructions provided on th
32、e MSDS.)10. Calibration and Standardization10.1 Calibration procedures vary from manufacturer to manufacturer. They are important to ensure accurate data. Include thefollowing periodic system verification steps:10.1.1 Wavelength Scale VerificationThis can be done with a didymium filter.10.1.2 Photom
33、eric Scale VerificationThis is to be done in accordance with manufacturers instructions with a certified liquidstandard. An APHA standard is suitable. Linearity is established using at least two different standard concentrations.10.1.3 Selection of Instrument Variables10.1.3.1 Select CIE illuminant
34、D65 and 10 standard observer.10.1.3.2 Select the total transmission (TTRAN) mode unless instructed by the manufacturer to use a different mode for theverification procedure.10.2 Pour mineral oil into a clean cuvette. Ensure that liquid completely covers the measurement area and that no air bubblesre
35、main below the meniscus. Follow the manufacturers instructions to perform the following steps before sample analyses and atleast every four hours when samples are being analyzed.10.2.1 Full-Scale StandardizationUse a cuvette filled with mineral oil to set the top of the neutral axis scale to 100 bys
36、imulating the case where all light is transmitted through the sample.10.2.2 Zero Scale StandardizationSet the bottom of the neutral axis scale to 0 by simulating the case where all light isabsorbed by the sample. Block the light beam by replacing the cuvette with an opaque object supplied by the man
37、ufacturer.11. Conditioning11.1 Condition liquids for measurement at 23 6 2C unless otherwise specified by contract or relevant material specification.NOTE 2The pure 4,4 isomer of methylenebis-(phenylisocyanate)methylene di(phenylisocyanate) (MDI) is a solid at 23C. Condition it formeasurement at 50
38、6 2C.12. Procedure12.1 Sample PreparationPour the sample into a clean cuvette. Ensure that liquid completely covers the measurement area andthat no air bubbles remain below the meniscus.12.2 Selection of Instrument Variables12.2.1Select CIE illuminant D65 and 10 standard observer.TABLE 2 Yellowness
39、Index Round Robin DataYI valuesStandard Material Viscosity Average SrASRBrCRDMineral OilPolyol A 475 mPA s(475 cP)1.08 0.01 0.19 0.04 0.52Polyol B 6500 mPa s(6599 cP)21.60 0.10 4.60 0.28 12.88Polyol B 6500 mPa s(6500 cP)21.60 0.10 4.60 0.28 12.88ASr= within laboratory standard deviation of individua
40、l replicates.BSR= between laboratories standard deviation of means of replicates.Cr = within laboratory critical interval between individual replicates (2.8 3 Sr)repeatability.DR = between laboratory critical interval between means of replicates (2.8 3 SR)reproducibility.D7133 11312.2.1 Select CIE i
41、lluminant D65 and 10 standard observer.12.2.2 Select the total transmission (TTRAN) mode.12.3 Selection of Color Scale and IndexSelect the CIELAB color calculated as defined in Practice E308 and the YellownessIndex calculated as defined in Practice E313.12.4 Analysis12.4.1 The mineral oil is read as
42、 a sample to ensure that the instrument is set up and reading correctly prior to sample analysis.Therefore, measure the cuvette of mineral oil in duplicate by following the manufacturers instructions for sample measurementin TTRAN mode. The average of two readings is to meet the following tolerances
43、: L* =100 6 0.1; a*= 0 6 0.1; b*= 0 6 0.1 andYI=06 0.25.12.4.2 Measure the cuvette of the sample in duplicate by following the manufacturers instructions for sample measurement inTTRAN mode.12.4.3 Average the resulting values for L*a*b* and YI.13. Calculation13.1 The instrument software is to automa
44、tically calculate the L*a*b* values in accordance with the equations defined inPractice E308 and the YI value in accordance with the equation in Practice E313.14. Report14.1 The report shall include the following:14.1.1 Date of measurement.14.1.2 Sample description and identification.14.1.3 Any chan
45、ges from the recommended parameters or conditions (for example, temperature of sample if different from 22236 2C or 50 6 2C for pure MDI, the use of a liquid other than mineral oil for standardization).14.1.4 L*a* b* values and YI value to two significant figures to the right of the decimal point.15
46、. Precision and Bias15.1 The precision data presented in this test method are representative of the conditions defined in the standard. However,material preparation and specific test conditions in the material specification can result in a deviation from the precision and biasrequiring separate stud
47、y.15.2 Table 1 is based on a round robin conducted in 2001 in accordance with Practice E180 involving four materials tested byten laboratories. For each material, all the samples were prepared at one source, but the individual specimens were prepared at thelaboratories that tested them. Each test re
48、sult was the average of two individual determinations (replicates). Each laboratoryobtained two test results for each material.15.3 Table 2 is based on a limited round robin conducted in 2001 involving two materials tested by four laboratories. For eachmaterial, all the samples were prepared at one
49、source, but the individual specimens were prepared at the laboratories that testedthem. Each test result was the average of two individual determinations (replicates). Each laboratory obtained two test results foreach material. (WarningThe explanation of “r” and “R” (15.4 through 15.4.3) are only intended to present a meaningful wayof considering the approximate precision of the test method. The data in Table 1 and Table 2 are not to be applied to acceptanceor rejection of materials, as these data apply only to the materials tested in the r
