ASTM D5767-2018 Standard Test Method for Instrumental Measurement of Distinctness-of-Image (DOI) Gloss of Coated Surfaces.pdf

1、Designation: D5767 17D5767 18Standard Test Method forInstrumental Measurement of Distinctness-of-Image (DOI)Gloss of Coated Surfaces1This standard is issued under the fixed designation D5767; the number immediately following the designation indicates the year oforiginal adoption or, in the case of r

2、evision, 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. Scope1.1 These test methods describe the measurement of the distinctness-of-image (DOI) gloss of coating s

3、urfaces usingelectro-optical measuring techniques.1.2 The coatings assessed shall be applied to planar rigid surfaces.1.3 Test MethodThe light through a small slit is projected on the specimen surface and its reflected image intensity ismeasured through a sliding combed shutter to provide a value of

4、 image clarity.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 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

5、 to establish appropriate safety, health, and environmental practices and determine the applicability ofregulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principl

6、es for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D523 Test Method for Specular GlossD823 Practices for Producing Films of Uniform Thickness of Pai

7、nt, Coatings and Related Products on Test PanelsD2457 Test Method for Specular Gloss of Plastic Films and Solid PlasticsD3964 Practice for Selection of Coating Specimens for Appearance MeasurementsD4039 Test Method for Reflection Haze of High-Gloss SurfacesE284 Terminology of AppearanceE430 Test Met

8、hods for Measurement of Gloss of High-Gloss Surfaces by Abridged GoniophotometryE691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method2.2 ISO Standards:3ISO 10216 Anodizing of aluminumAluminum and its alloysInstrumental determination of image clarity of ano

9、dic oxidationcoatingsInstrumental methodAlloysInstrumental Determination of Image Clarity of Anodic Oxidation CoatingsInstrumental MethodISO 17221 PlasticsDetermination of image clarityImage Clarity (degree of sharpness of reflected or transmitted image)ISO 116641 Colorimetry Part 1CIE standard colo

10、rimetric observersISO 116642 Colorimetry Part 2CIE standard illuminants3. Terminology3.1 DefinitionsTerms and definitions in Terminology E284 are applicable to these methods.1 This test method is under the jurisdiction of ASTM Committee E12 on Color and Appearance and is the direct responsibility of

11、 Subcommittee E12.03 on Geometry.Current edition approved June 15, 2017Oct. 1, 2018. Published September 2017October 2018. Originally approved in 1995. Last previous edition approved in 20122017as D5767 95 (2012).D5767 17. DOI: 10.1520/D5767-17.10.1520/D5767-18.2 For referencedASTM standards, visit

12、theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual 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,

13、 NY 10036, http:/www.ansi.org.This 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 changes accurately, ASTM recommend

14、s 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.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.1.1 distinctness

15、-of-image (DOI) gloss, naspect of gloss characterized by the sharpness of images of objects produced byreflection at a surface. E2843.1.1.1 DiscussionThis quality is sometimes called image clarity.3.1.2 gloss reflectance factor, Rs, nratio of the specularly reflected part of the (whole) flux reflect

16、ed from the specimen to theflux reflected from a specified gloss standard under the same geometric and spectral conditions of measurements. E2843.1.2.1 DiscussionThe gloss standard may be a black glass or mirror and may be assigned one of a variety of scale values as specified.3.1.3 specular angle,

17、nangle of reflection equal and opposite to the angle of incidence. E2844. Significance and Use4.1 An important aspect of the appearance of glossy coating surfaces is the distinctness (clarity) of images reflected by them.The values obtained in this measuring procedure correlate well with visual rati

18、ngs for DOI (image clarity).4.2 Although Test Methods D523 and D4039 are useful in characterizing some aspects of glossy appearance, they do notprovide satisfactory ratings for DOI (image clarity).4.3 The measurement conditions given conform to the conditions specified in Test Methods E430.4.4 The m

19、easurement conditions given in this test method conform to the conditions specified in ISO 10216.4.5 The scale values obtained with the measuring procedures of this test method range from 0 to 100 with a value of 100representing perfect DOI (image clarity).4.6 The DOI (image clarity) scale value doe

20、s not, of itself, indicate any specific cause for reduction in reflected image sharpness.Surface irregularities such as haze, orange peel, and wrinkle, when present, may be cited as causes for reduction of imagesharpness.5. Apparatus5.1 Image Clarity Meter, 4consisting of a light source, a sliding c

21、ombed shutter, a photo-receiver, and a device for analyzingimage intensities (see Fig. 1).5.2 PrincipleThe light through a small slit is projected on the specimen surface and its reflected image intensity through asliding combed shutter is measured.5.3 Geometric ConditionsThe axis of the incident be

22、am shall be 60 from the perpendicular to the specimen surface and thephoto-receiver shall be at the mirror reflection of the axis of the incident beam. The source slit is 0.1 6 0.02 mm in width andthe photo-receiver shall receive a reflected image through a combed shutter of 18 slits of 7.5 mm in wi

23、dth.NOTE 1A more complete description of the spectral response function of this instrument is in ISO 17221.5.4 Spectral ResponseThe light source and the photometer shall be used in conjunction with a filter to provide an outputcorresponding to the photopic standard luminous efficiency V(), which is

24、identical to the color-matching function y() specifiedin ISO 11664-1, under CIE standard illuminantAas specified in ISO 11664-2.The output of the photodetector shall be proportionalto the incident flux, to within 1 % of the incident flux, over the range used. The spectral and photometric characteris

25、tics of the lightsource and photometer shall be kept constant during measurements.5.5 SlitDimensions of the slit are 0.03 mm 6 0.01 in width and not less than 20 mm in length.5.6 Optical MaskThe optical mask consists of opaque and transparent lines having the same width and spacing. Six differentgro

26、ups of lines having different widths are utilized. An optical mask is illustrated in Fig. 2. Table 1 defines the dimension of theline widths and spacing in Groups 1 through 6.6. Preparation and Selection of Test Specimens6.1 This test method does not cover techniques for the preparation of test spec

27、imens. Whenever preparation of test specimensis required, use one of the procedures given in Practices D823. Selection of specimens for measurement should be done inaccordance with Practice D3964.4 The sole source of supply of the meter Model HA-ICM, Image Clarity, known to the committee at this tim

28、e is Suga Test Instruments Co., Ltd., 414, Shinjuku 5chome,Shinjuku-ku, Tokyo, 160 Japan. If you are aware of alternative suppliers, please provide this information to ASTM International Headquarters. Your comments will receivecareful consideration at a meeting of the responsible technical committee

29、,1 which you may attend.D5767 1827. Reference Standards7.1 The following analysis may be used to establish the specular gloss value, Gs, of the working standard:Q 5 n!22sin2! #12 (1)ri 5Fcos! 2Qcos! 1Q G2(2)r5Fn !2 cos! 2Qn !2 cos! 1Q G2(3)I 5 0.5r!1ri!# (4)DIMENSIONS HA-ICMASlit0.1 mmBLight Angle22

30、CSlit/Lens Dist.50 mmDLensf 50 mmELens/Test Spec. Dist.50 mmFTest Spec./Lens Dist.50 mmGLensf 50 mmHLens/Com. Shut. Dist.50 mmILight Angle22JShut./Slit Length10 mmKShut./Slit Width0.5 mmLShut./Slit Space0.5 mmDIMENSIONS HA-ICMASlit0.1 mmBLight Angle22CSlit/Lens Dist.50 mmDLensf 50 mmELens/Test Spec.

31、 Dist.50 mmFTest Spec./Lens Dist.50 mmGLensf 50 mmHLens/Com. Shut. Dist.50 mmILight Angle22JShut./Slit Length10 mmKShut./Slit Width0.5 mmLShut./Slit Space0.5 mmFIG. 1 Diagrammatical Representation of Image Clarity MeasurementD5767 183Gs 5 100 IWSIPS(5)where: = angle of incidence of the collimated ra

32、y with respect to the normal in the rarer optical medium,n = ratio of the index of refraction of the denser optical medium divided by the density of the rarer optical medium,Q = placeholder for a reocurring expression in the equations,r = intensity, relative to that of the incident wave, of the spec

33、ular reflection for the part of the reflected wave polarizedperpendicular to the plane of incidence,r? = intensity, relative to that of the incident wave, of the specular reflection for the part of the reflected wave polarized parallelto the plane of incidence,I = mean intensity of parallel and perp

34、endicular waves,IWS = refers to the I value of the working standard,IPS = refers to the I value of the primary standard, andGS = specular gloss reading of a working standard with respect to the reading of the primary standard at a nominal value of100 gloss units.KeyA opaque area Group 1 transparent

35、and opaque lines each 2.0 mm in widthB transparent area Group 2 transparent and opaque lines each 1.0 mm in widthC width of opaque area Group 3 transparent and opaque lines each 0.5 mm in widthD width of transparent area Group 4 transparent and opaque lines each 0.25 mm in widthGroup 5 transparent a

36、nd opaque lines each 0.125 mm in widthGroup 6 opaque line each 1.0 mm in widthFIG. 2 Image Clarity Optical MaskTABLE 1 Optical Mask (dimensions)AGroup No. Optical Mask Line Widthmm Quantity Tolerancemm Group Widthmm Angle of Line Width from LensEFL in degrees1 2.000 4 0.200 16 0.88142 1.000 6 0.100

37、12 0.44073 0.500 9 0.050 9 0.22044 0.250 16 0.025 8 0.11025 0.125 21 0.013 5.25 0.05516 1.000(only opaque)1 0.100 1 0.4407A The dimensions of the optical mask cited here are dependent on many factors including the system geometry, optical design, etc.D5767 1847.1.1 For additional information on Eq 1

38、, see Wyszecki and Stiles.5Note 2Index of Refraction SensitivityEach 0.01 increment in the index of refraction of polished black glass produces achange in the measured value of approximately 1.6 scale units for the 60 geometry.Note 3To determine the scale value:7.1.1.1 Calculate the first surface Fr

39、esnel reflectance (see Test Method D2457) for nD = 1.567. The specular angle is 60. Thecalculated value is 10.0056 % or 100.0 units.7.1.1.2 Assign this the full scale value of 100.0 units (see Test Method D523).7.1.1.3 Repeat the calculation for nD = 1.527. Using the same specular angle of 60, the c

40、alculated value is 9.3636 % or 93.6units.7.1.1.4 The new scale value for the working black, glass standard for 60 is 100 (9.3626/10.0056) = 0.9357 or 93.6 units.7.2 Verification StandardsDe-polished, opaque, black glasses and ceramic tiles having uniform, planar surfaces are suitablefor verification

41、 standards when calibrated against a primary or working standard on an image clarity meter known to meet therequirements of the test method.8. Procedure8.1 StandardizationStandardize by adjusting the apparatus to read the assigned value of the polished black working standard.8.2 VerificationRead the

42、 verification standards whose assigned values lie within the range of the instrument scale. Thereadings of the verification standards should agree within 61 unit of their assigned values.8.3 Place the specimen to be read on a flat surface.8.4 Place the apparatus on the specimen surface and read C, t

43、he value of image clarity. Take readings at three different areasof the specimen surface.8.5 Take reading of the working standard at the end of series of specimen readings to ensure that the apparatus has remainedin calibration throughout the operation.9. Calculation9.1 Calculate the image clarity v

44、alue from the maximum and the minimum light intensities, which the photo-receiver measures,using Eq 6 (see Fig. 23 and Fig. 34):C 5M 2mM1m 3100 (6)where:C = image clarity value, %,M = maximum light intensity, andm = minimum light intensity.9.2 When the test specimen has a completely flat and smooth

45、surface and the shutter is slid laterally, the reflected image of theslit at the sliding combed shutter passes completely through the space of the comb when the center of the comb space coincideswith the image. This generates a maximum light intensity on the photo-receiver. When not completely flat

46、and smooth, dependingon the degree of dispersion of the light, the image cannot pass through the comb completely and generates a minimum lightintensity. These maximum and minimum light intensities are used to calculate the image clarity value.5 Wyszecki, G. and Stiles, W. S., Color Science: Concepts

47、 and Methods, Quantitative Data and Formulae, Second ed., John Wiley and Sons, New York, 1982, p. 52FIG. 23 Wave FormStandardizationD5767 1859.3 The instrument calculates and displays the image clarity value, C, directly.10. Report10.1 Report the following information:10.1.1 Image Clarity Values:10.

48、1.1.1 Mean image clarity values and10.1.1.2 Comb width.10.1.2 Operational Logistics:10.1.2.1 Date and location of test performed,10.1.2.2 Operator performing test,10.1.2.3 Facility where test performed,10.1.2.4 Name of test instrument,10.1.2.5 Model number of test instrument,10.1.2.6 Last calibratio

49、n date of instrument, and10.1.2.7 Calibration standard identification.10.1.3 Sample Identification:10.1.3.1 Information regarding identification of sample and10.1.3.2 Information regarding direction of measurement on sample.11. Precision and Bias11.1 Precision:11.1.1 The experiment and data gathered for this section were acquired and computed in accordance with the requirements asoutlined in Practice E691.6 The materials used as test specimens to derive