1、Designation: D3134 97 (Reapproved 2008)1D3134 15Standard Practice forEstablishing Color and Gloss Tolerances1This standard is issued under the fixed designation D3134; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of las
2、t revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1 NOTECorrections were made editorially in Footnote 4, 7.2.1, and Section 12 in December 2008.INTRODUCTIONPermissible color and gloss
3、 deviations from a standard are generally dependent upon the colordiscrimination of the observer, on the lighting and surround in which the material is viewed, and onspecial considerations related to the design, manufacture, and practical usage of the colored materialor object. The tolerances, there
4、fore, may be influenced by economic, technical, psychological, andpractical requirements. In many circumstances, acceptability of color and gloss deviations from astandard may differ appreciably from the perceptibility of deviations such as on-tone fadingpreferences, large tolerances for luminance v
5、ariation, nongreen bias, or nonyellow bias. perceptibilityfor many reasons. With proper allowances, perceptibility data can be used as an aid to developpermissible tolerances. Finally, the sum of all these considerations should result in a specificationacceptable to both buyer and seller.1. Scope1.1
6、 This practice describes a procedure for establishing tolerances and evaluating the color and gloss of specimens with respectto specified standards. This practice is appropriate for nonfluorescent opaque specimens.1.2 This practice does not indicate the extent of tolerances, but gives guidance on ho
7、w they can be set. For product specification,the tolerances between specimens and the specified standard should be agreed upon between the purchaser and the seller.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof th
8、e user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D523 Test Method for Specular GlossD1535 Practice for Specifying Color by the Munsell SystemD1729 Practice for
9、 Visual Appraisal of Colors and Color Differences of Diffusely-Illuminated Opaque MaterialsD2244 Practice for Calculation of Color Tolerances and Color Differences from Instrumentally Measured Color CoordinatesD3964 Practice for Selection of Coating Specimens for Appearance MeasurementsD4449 Test Me
10、thod for Visual Evaluation of Gloss Differences Between Surfaces of Similar AppearanceD5531 Guide for Preparation, Maintenance, and Distribution of Physical Product Standards for Color and GeometricAppearance of CoatingsE284 Terminology of AppearanceE308 Practice for Computing the Colors of Objects
11、by Using the CIE SystemE312 Practice for Description and Selection of Conditions for Photographing Specimens Using Analog (Film) Cameras andDigital Still Cameras (DSC)E805 Practice for Identification of Instrumental Methods of Color or Color-Difference Measurement of Materials1 This practice is unde
12、r the jurisdiction of ASTM Committee E12 on Color and Appearance and is the direct responsibility of Subcommittee E12.11 on Visual Methods.Current edition approved Dec. 1, 2008Jan. 1, 2015. Published December 2008February 2015. Originally approved in 1972. Last previous edition approved in 20032008a
13、s D3134 97 (2003).(2008)1. DOI: 10.1520/D3134-97R08E01.10.1520/D3134-15.2 For referencedASTM standards, visit 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 AS
14、TM website.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 recommends that users consul
15、t 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 States1E1164 Practice for Obtaining Spectrom
16、etric Data for Object-Color EvaluationE1331 Test Method for Reflectance Factor and Color by Spectrophotometry Using Hemispherical GeometryE1345 Practice for Reducing the Effect of Variability of Color Measurement by Use of Multiple MeasurementsE1349 Test Method for Reflectance Factor and Color by Sp
17、ectrophotometry Using Bidirectional (45:0 or 0:45) GeometryE1360 Practice for Specifying Color by Using the Optical Society of America Uniform Color Scales SystemE1499 Guide for Selection, Evaluation, and Training of ObserversE1541 Practice for Specifying and Matching Color Using the Colorcurve Syst
18、em (Withdrawn 2007)3E1708 Practice for Electronic Interchange of Color and Appearance Data2.2 CIE Publication:No. CIE S 014-4/E2007Publication 015 Colorimetry 2nd ed.42.3 ISO Standard:ISO 15930 Graphic Technology Part 4: Complete exchange of CMYK and spot colour printing data using PDF 1.4 (PDF/X-la
19、)3. Terminology3.1 DefinitionsFor definitions of terms related to this practice see Terminology E284.4. Summary of Practice4.1 This practice consists of recommendations for the selection of a standard, the necessary physical measurements to assessthe permanence of the standard to reproduce it when n
20、eeded, and to establish tolerances.4.2 Recommendations are given for the determination of the conformance of a specimen to preestablished color and glosstolerances by instrumental or visual means.5. Significance and Use5.1 Color specifications are centered around exact positions in color space. Corr
21、espondingly, gloss specifications are centeredaround an exact position on the gloss scale. Because it is difficult to achieve these exact positions repeatedly, it is necessary tospecify tolerances that are acceptable to both the buyer and the seller. This practice details the procedure for accomplis
22、hing thisgoal.6. Specimens6.1 The exact method of preparation of the specimen shall be agreed upon between the purchaser and the seller. However, forthe highest precision in instrumental measurements the specimens should be opaque, uniform in color, plane, and uniform intexture. The specimens should
23、 be relatively permanent, and capable of being cleaned. Preferred sizes of specimens for visualevaluation are given in Practice D1729, the specific size being governed by the use of the specimens.7. Procedure7.1 Selection and Specification of Color and Gloss Standard:7.1.1 Select a standard in accor
24、dance with Practice D3964 that is preferably the same type of material as the specimens to beevaluated for color or gloss, or both. Prepare, in sufficient quantity, secondary standards in accordance with Guide D5531 that arerepresentative of the desired color and gloss, in the permanent material. St
25、andards should have the same spectral characteristicsas the manufactured product. This is usually accomplished by use of the same colorant composition, incorporated in the samemanner into the same material. The standard should have the same texture as the manufactured product.7.1.1.1 In order to obt
26、ain a permanent record, use Practice E805 and either Test Method E1331 or Test Method E1349 tocorrectly identify the instrumental measurement method. Measure the color in accordance with Practices E1164 and E805. Reportthe color as described in Practice E308. Do this even if the standard is textured
27、. (If the standard is textured, note the textureorientation during measurement.) The variability of the measurements due to texture may be reduced by following therecommendations outlined in Practice E1345.7.1.1.2 Visual Color AssessmentUse Guide E1499 to select an observer for the assessment. Asses
28、s and specify the color interms of a color system described in Practices D1535, E1360, or E1541.7.1.1.3 Measure the gloss in accordance with Test Method D523, or evaluate it in accordance with Test Method D4449.7.1.1.4 Employ photography for permanently recording the appearance of the surface textur
29、e (see Practice E312). WhilePractice D3134 does not deal with texture tolerances or specifications, it should be recognized that significant differences in surfacetexture between standard and test specimens significantly affect both color and gloss, whether examined visually or instrumentally.In the
30、 case of visual evaluation of the effect of color and gloss, differences can be minimized by strict adherence to recommendedilluminating and viewing geometry (see Practice D1729).3 The last approved version of this historical standard is referenced on www.astm.org.4 Available from CIE (International
31、 Commission on Illumination), http:/.D3134 1527.2 Selection and Specification of Color Tolerances:7.2.1 The purchaser and the seller shall agree on color tolerances with respect to a previously selected standard and on the colorscales in which they are expressed. Selection of the magnitude and direc
32、tion of color tolerances shall be based on carefulconsideration of all applicable factors. For example, tolerances may be selected on the basis of perceptibility of the magnitude ofcolor difference, rejection of or closer limits on certain directions of color difference, and costs of controlling the
33、 magnitude anddirection of color difference. Recommendations on color scales appear in CIE Publication No. CIE S 014-4/E2007Publication 015and Practice E308.7.2.1.1 Express color differences between the specimen and the standard in terms of a set of three independent parameters. TheCIE 1976 L*a*b* (
34、CIELAB) approximately uniform color space and color difference equations have been recommended for useby the International Commission on Illumination (CIE). See Practice D2244 and Practice E308. While this color metric (CIELAB)is convenient for expressing color differences, it must be understood tha
35、t a given calculated color difference in one region of colorspace may not represent the same visual difference in other regions of color space.7.2.2 Gloss differences can affect instrumental measurement of color differences. Large gloss differences between visuallyidentical colors can cause their co
36、lor measurements to exhibit larger color differences than in fact exist. When using historical datato establish color tolerances, exercise care to limit the specimens to those that have quite similar gloss values. When establishinggloss tolerances, be aware that changes in gloss values may have an e
37、ffect upon color measurements.7.2.3 When color difference formulae are used in practice, it is often desirable to identify the components of color difference,in terms of correlates of lightness, hue, and perceived chroma (saturation). It is also desirable to express color specifications interms of s
38、uch correlates. The CIE terminology appropriate to this usage is CIE 1976 lightness, CIE 1976 hue-angle, hab, and CIE1976 chroma, C*ab. Refer to Practice D2244 and Practice E308 for equations and definitions. The CIELAB 1976 hue-angle andchroma are illustrated in Fig. 1.7.2.4 The CIELAB opponent-col
39、or red-green coordinate a*, and the yellow-blue coordinate b* are defined in Practice D2244and Practice E308.7.2.5 Graphical Interpretation of Historical Data:7.2.5.1 Color tolerances can be determined from a graphical interpretation of historical data (batches accepted, rejected, orconsidered borde
40、rline). Fig. 2 (a) and Fig. 3(b) show plots of specimens rated by multiple observers with respect to how well theymatch a standard, along with figures defining the tolerances. To illustrate the principle recommended: (1) rate a number ofspecimens for acceptability, (2) plot them, and (3) prepare to
41、draw the tolerance figure dictated by the data.7.2.5.2 In such cases it is customary to plot the hue angle of the standard by drawing a line from the origin (0, 0) through thestandard color on the a*b* plot. This line of constant hue becomes the major axis. Similarly, a line perpendicular to thecons
42、tant-hue line and passing through the standard color is a line of constant chroma (or saturation) and becomes the minor axisof the ellipse, if the data plot indicates the ellipse should be symmetrical around the standard color. These lines assist in drawingthe tolerance ellipse, Fig. 2(a).NOTE 1Hue
43、angle is measured in degrees starting with hab = 0 in the + a* (red) direction and increasing counterclockwise. Chroma is measured asthe length of the line from the neutral point (a* = b* = 0) to the sample point. Sample Point 2 has a larger value of hab than Point 1 and therefore isyellower in hue.
44、 Point 2 also has a smaller value of Cab* than Point 1 and is therefore lower in chroma or duller.NOTE 2Original source is Billmeyer, F. W., Jr., and Saltzman, M., Principles of Color Technology, 2nd ed., John Wiley and Sons, New York, NY,1981. (Reprinted by permission of John Wiley perhaps it will
45、be an ovoid instead of an ellipse; its major axis may deviate from the direction of constant hue; andthe standard color may be far from its center. Frequently when it is necessary to set color tolerances, the amount of historicalaccept-reject data will be too modest for this purpose. It is therefore
46、 necessary to monitor tolerances, once set, to ensure that theyappropriately address the color quality control requirement.7.2.9 When tolerance standards are prepared to illustrate the color in the hue, lightness, and saturation or chroma attributes ofcolor space and to allow visual interpretation o
47、f the conformity of color, inspection should be under specified light sourcesfollowing the recommendations in Practice D1729. Gonioapparent coatings or materials require special methodologies for viewingand measurement.7.3 Selection and Specification of Gloss Tolerances:7.3.1 The gloss tolerances ar
48、ound the gloss of the standard may be expressed in gloss units (See Test Method D523) or as apercent.7.3.2 With few exceptions, the visual gloss tolerance will be symmetrical around the nominal value of the standard. It will benecessary to determine experimentally the instrumental readings that corr
49、espond to the required visual differences.(a) Chromaticity TolerancesNOTE 1The standard color is at the 0,0 point and the tolerance ellipses define permissible differences from it. Fig. 2(a) shows chromaticity tolerancesin a* and b*; Fig. 3(b) shows lightness tolerances in L*, with a* data also shown.FIG. 2 Plots of Instrumental Results on Color Specimens Along With Their Visual Acceptability RatingsD3134 1547.3.3 When the gloss desired is at or near the maximum or minimum gloss attainable, it is customary to specify a single glossreading and th
