1、Designation: D 4039 93 (Reapproved 2004)Standard Test Method forReflection Haze of High-Gloss Surfaces1This standard is issued under the fixed designation D 4039; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last rev
2、ision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method describes a procedure for using twospecular gloss measurements to obtain a haze index forhigh-gloss nonmetal
3、lic specimens (1-4).2It is particularlyuseful for evaluating the haze in clear finishes on nonglossysubstrates, and the haze in reflected images produced by thesurfaces of opaque glossy pigmented finishes.1.2 This standard does not purport to address all of thesafety concerns, if any, associated wit
4、h its use. It is theresponsibility of the user of this standard 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:3D 523 Test Method for Specular GlossD 823 Practices for Producing F
5、ilms of Uniform Thicknessof Paint, Varnish, and Related Products on Test PanelsD 3964 Practice for Selection of Coating Specimens forAppearance MeasurementsE 284 Terminology of AppearanceE 430 Test Method for Measurement of Gloss of High-Gloss Surfaces by Goniophotometry3. Terminology3.1 Definitions
6、:3.1.1 specular gloss, nratio of flux reflected in speculardirection to incident flux for a specified angle of incidence andsource and receptor angular apertures.3.1.2 haze, nin reflectionscattering of light at the glossysurface of a specimen responsible for the apparent reduction ofcontrast of obje
7、cts viewed by reflection at the surface.3.2 Definitions of Terms Specific to This Standard:3.2.1 60 specular gloss G60, nspecular gloss measuredwith the 60 geometry specified in Test Method D 523.3.2.2 20 specular gloss G20, nspecular gloss measuredwith the 20 geometry specified in Test Method D 523
8、.3.2.3 haze index, H, na measure of reflection haze, whereH =G60G20.3.3 Appearance terms used in this standard are defined inTerminology E 284.4. Summary of Test Method4.1 Measurements of 60 and 20 specular gloss are madeon a specimen. The haze index is computed as the differencebetween the two meas
9、urements.4.2 This test method is applicable to nonmetallic specimenshaving a 60 specular gloss value greater than 70 in accor-dance with Test Method D 523.4.3 Both 60 and 20 specular gloss depend upon therefractive index of the material being measured. Because 20gloss changes much more rapidly with
10、index than 60 gloss,the reflection haze value of a specimen also depends on theindex of refraction of the material. To establish a correction forthe effect of refractive index would require its measurement foreach material, which is inconvenient. Comparisons of reflec-tion haze evaluated by this tes
11、t method are therefore limited tospecimens of essentially the same refractive index.5. Significance and Use5.1 Measured gloss values of specimens depend on theangle of illumination, refractive index of the material, and thegeometric distribution of the reflected light.5.2 Haze is produced by irregul
12、arities in the reflectingsurface that affect the distribution of flux reflected around thespecular angle. The procedures specified in Test Method D 523are not designed to measure reflected-flux scattering character-istics of high-gloss finishes, particularly where specimenshaving different surface r
13、efractive indexes are being compared.A better index of scattering can be obtained by making twospecular reflectance measurements, that is, the use of tworeceptor apertures of different size.5.3 In this test method, values for reflection haze areobtained from two measurements of specular gloss, one m
14、adewith a large receptor aperture and the other made with a smallreceptor aperture. The geometric conditions have been chosen1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01
15、.26 on Optical Properties.Current edition approved November 1, 2004. Published November 2004.Originally approved in 1981. Last previous edition approved in 1999 asD 4039 93 (1999).2Boldface numbers in parentheses refer to the list of references at the end of thistest method.3For referenced ASTM stan
16、dards, 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.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken,
17、PA 19428-2959, United States.to permit the use of glossmeters that provide 60 specular glossmeasurements (large receptor aperture) and 20 specular glossmeasurements (small receptor aperture) as specified in TestMethod D 523.5.4 An additional method for the measurement of reflectionhaze is given in T
18、est Method E 430.6. Apparatus6.1 Glossmeter(s), capable of measuring 60 and 20 specu-lar gloss in accordance with the specifications given in TestMethod D 523.7. Preparation and Selection of Test Specimens7.1 This test method does not cover preparation techniques.When a test requires the preparation
19、 of specimens from a liquidcoating, specify the techniques of specimen preparation.7.2 Select test specimens in accordance with PracticeD 3964.7.2.1 To determine the maximum gloss obtainable from amaterial, such as a paint or a varnish, use methods in PracticesD 823 to produce a film of uniform thic
20、kness on a smooth,planar substrate.7.2.2 Use surfaces of good planarity, because surfacewarpage, waviness, or curvature may affect test results signifi-cantly. The directions of brush marks or similar texture effectsshould be parallel to the plane of the axis of the two beams.8. Calibration and Stan
21、dardization8.1 Calibrate the glossmeters with primary and secondaryworking standards in accordance with the procedures given inTest Method D 523.8.2 The gloss scales in Test Method D 523 are defined byadopting the scale value of 100 for polished black glass with arefractive index of 1.567. However,
22、the polished black glassstandards used in this test method usually have a lowerrefractive index (approximately 1.527). The appropriate scalevalues of such standards have been calculated in Test MethodD 523; they are 93.6 for the 60 geometry and 89.2 for the 20geometry.NOTE 1Because of the difference
23、 in scale values for the two geom-etries, the haze-free standard or a haze-free specimen of refractive index1.527 will have a haze index H = 93.6 89.2 = 4.4.9. Procedure9.1 Select an area near the center of the test specimen anddetermine the 60 specular gloss.9.2 Determine the 20 specular gloss on t
24、he same area of thespecimen.10. Calculation10.1 Compute the haze index, H, as follows:H 5 G602 G20(1)where:G60= value of 60 specular gloss andG20= value of 20 specular gloss.11. Report11.1 Report the following information:11.1.1 For each specimen, the measured G60and G20valuesand the computed haze i
25、ndex, H.11.1.2 Where preparation of the test specimen has beennecessary, describe or otherwise identify the method of prepa-ration.11.1.3 Identify the glossmeter used by make and model.11.1.4 Identify the gloss standards used.12. Precision12.1 On the basis of interlaboratory studies of this proce-du
26、re in which six laboratories conducted single determinationson eight high-gloss coatings differing in visually perceivedreflection haze, the within-laboratory standard deviation forhaze index values was found to be 2.5.12.2 Based on these standard deviations, the followingcriteria should be used for
27、 judging the acceptability of singledeterminations at the 95 % confidence level.12.2.1 RepeatabilityTwo results obtained by a singleoperator should be considered suspect if they differ by morethan 2 units of haze index.12.2.2 ReproducibilityTwo results obtained by operatorsin different laboratories
28、should be considered suspect if theydiffer by more than 7 units of haze index.13. Keywords13.1 haze; high gloss; reflection hazeREFERENCES(1) Nimeroff, I., “Two-Parameter Gloss Methods,” Journal of Research,National Bureau of Standards, Vol 58, No. 3, March 1957, pp.127135.(2) Hammond, III, H. K., a
29、nd Nimeroff, I., “Measurement of Sixty-DegreeSpecular Gloss,” Journal of Research, National Bureau of Standards,Vol 44, No. 6, June 1950, p. 585.(3) Horning, S. C., and Morse, M. P., “The Measurement of the Gloss ofPaint Panels,” Offcial Digest, Federation of Paint and Varnish Pro-duction Clubs, Vol
30、 19, No. 266, March 1947, p. 153.(4) Hunter, R. S., “Gloss Evaluation of Materials,” ASTM Bulletin, No.186, December 1952, p. 48.D 4039 93 (2004)2ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of
31、 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 technical committee and must be reviewed every five
32、 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 consideration at a meeting of theresponsible technical co
33、mmittee, 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 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 4039 93 (2004)3
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