意味と目的
5.1 3 つの刺激値に基づくオリジナルの CIE カラー スケール X, Y, Z and chromaticity coordinates x, y is not visually uniform. Each subsequent color scale based on CIE values applies a weighting factor to provide a degree of uniformity so that the color differences across regions of the color space will be more comparable. 一方で, it is unlikely that the same color differences obtained for the same samples evaluated in different color scale systems. 混乱を避けるために, comparisons should be made only when color differences or associated tolerances between samples are obtained for the same color scale system. For all colors of the specimen, there is no simple factor that can be used to precisely convert the color difference or color tolerance in one system into units of difference or tolerance in another system.

5.2 Color Difference E00 in Δ is highly recommended to use units (6) E* blood group units in the range of 0.0 to 5.0Δ. This color difference equation is applicable and widely used in industrial and commercial applications, including but not limited to automotive, コーティング, 化粧品, インク, 梱包, 塗料, プラスチック, 印刷, security and textiles.

5.3 Users of the color tolerance equation have found the addition of the three vector color difference components into a single scalar value in each system to be very useful in determining whether the sample color is within the tolerance specified by the standard. しかし, in order to control for color in production, 標準からの偏差の大きさだけを知るだけでなく、, しかし、この偏差の方向も. Information about the direction of small color differences can be included by listing the components determined by the three instruments for color differences.

5.4 Color tolerance selection based on instrument values should be carefully related to a visual assessment of the acceptability of hue, 練習 D1729 を使用して得られた明るさと彩度の差. ここで紹介する 3 つの公差方程式は、繊維やプラスチックのデータに基づいて広範囲にテストされています。, 視覚的評価と一致することが示されています, within the experimental uncertainty of visual judgments. This means that the equation itself misclassifies color differences whose frequencies are no greater than those of very experienced visual color matchers.

5.5 Although color difference and color tolerance equations are commonly applied to a variety of light sources, それらは派生または最適化されています, または両方, for daylight illumination. A good correlation with visual judgment may not be obtained when calculations are performed using other light sources. The use of tolerance equations in conditions other than daylight conditions requires visual confirmation of homochromic levels according to practice D4086.

ASTM 2244-2022 “器械色座標を使用した色の許容限界と色差の計算”

の範囲
1.1 This practice includes the calculation of color tolerances and small color differences between opaque specimens, such as painted panels, プラスチックパッチまたは繊維サンプル, based on color coordinates measured by an instrument based on daylight illumination. Practice D4086 should be used to verify instrumental results if it is suspected that specimens may be metamorphic, あれは, have different spectral curves despite visually similar colors. The tolerances and differences determined by these procedures are expressed in CIE 1976 CIELAB manual color space (1), 2 CMC公差単位 (2), CIE94公差単位 (3), DIN99o color difference formula given in DIN 6176 (4), or approximately uniform visual color vision in CIEDE2000 color difference units (5).

1.2 For the Product specifications, the Buyer and the Seller shall agree on the allowable color tolerance between the specimen and the reference and the procedure for calculating the color tolerance. Specific color tolerances may be required for each material and use condition, その他の見た目の要素として (例えば, サンプルの近接性, 光沢, とテクスチャー) may affect the correlation between the size of the measured color difference and its commercial acceptability.

1.3 この規格は、すべての安全問題に対処することを目的としたものではありません, もしあれば, その使用に関連する. 適切な安全性を確立するのは、この規格の使用者の責任です。, 健康および環境慣行を確認し、使用前に規制制限の適用可能性を判断するため.

1.4 この国際規格は、国際規格開発の原則に関する決定で確立された国際的に認められた標準化原則に従って開発されました。, 世界貿易機関の貿易の技術的障壁に関する委員会が発行したガイドラインと勧告.