GB/T 44945-2024 in English

GB/T 44945—2024 Standard Overview

The National Standard of the People's Republic of China GB/T 44945—2024 "Quantitative Chemical Analysis of Mixtures of Mulberry Silk and Tussah Silk in Textiles" was issued on November 28, 2024 and officially implemented on June 1, 2025. This standard specifies the test method for determining the content of mulberry silk and tussah silk in textile products by chemical analysis, and is applicable to textiles containing these two types of silk.

Background of Standard Formulation

With the development of the textile industry, the demand for testing mixed fiber products is increasing. The formulation of GB/T 44945—2024 fills the gap in the quantitative analysis method of mixtures of mulberry silk and tussah silk, and provides an important basis for quality control and international trade of textiles.

Comparison of standard frameworks

Technical details

Test principle

The standard specifies two main test methods: 56% sulfuric acid method and calcium chloride/ethanol (or calcium nitrate) method.

• 56% sulfuric acid method:Use sulfuric acid solution to dissolve mulberry silk, and calculate the tussah silk content by the mass of the residue. Applicable to the detection of ordinary textiles.
• Calcium chloride/ethanol method:Use calcium chloride/ethanol solution or calcium nitrate solution to dissolve mulberry silk, suitable for samples sensitive to high temperatures.

Reagents and Instruments

The standard requires the use of analytically pure reagents, and clearly specifies the technical parameters of instruments and equipment:

Implementation Suggestions

To ensure the effective implementation of the standard, it is recommended:

• The laboratory should be equipped with instruments and equipment that meet the requirements and calibrate them regularly.
• Operators must undergo professional training and be familiar with the standard details and safety precautions.
• In actual testing, the appropriate method (sulfuric acid method or calcium chloride/ethanol method) should be selected according to the characteristics of the sample.

Case Analysis

For example, when testing a batch of blended fabrics, if the 56% sulfuric acid method is used for testing, the following steps should be noted:

1. Sampling: Samples are taken according to the sampling method specified in Appendix A of the standard.
2. Dissolution: Add 100mL of sulfuric acid solution per gram of sample and oscillate at 25℃±2℃ for 30 minutes.
3. Filtration and washing: Separate the residue and wash it multiple times to ensure that the soluble components are completely removed.
4. Drying and weighing: Dry the residue at high temperature and accurately measure its mass.