GB/T 21878-2025 "Water-soluble dyes—Determination of shade and relative strength" replaces the 2008 edition and is applicable to the determination of shade and relative strength of water-soluble dyes. The standard adds terms, definitions, reagents, and other content, optimizes test methods, and clearly specifies that the sample and reference sample are prepared into solutions under the same conditions. The relative strength is calculated by measuring absorbance values using a spectrophotometer, while the shade is visually assessed when absorbance values are similar. This provides a scientific basis for quality control in dye production and selection at the application end, ensuring the accuracy and comparability of test results.
This summary is not the original standard text and is for reference only. For accurate information, please obtain it through official channels.
| Status | Active | ||
|---|---|---|---|
| CCS | G55 | ICS | 71.100.01;87.060.10 |
| Release Date | 2025-08-29 00:00:00 | Implementation Date | 2026-03-01 00:00:00 |
