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What is 6A Grade Silk?

2024.07.13

                                                                   What is 6A grade Silk?

               6A refers to the grade of raw silk (just the quality standard of the silk thread).

               Even fabric woven from 6A silk can have flaws, though there will be fewer.

The quality of the fabric is not just about the silk grade; it also depends on the weaving quality and the handling during various processing stages. Even the best raw materials can be compromised by poor weaving machinery or improper dyeing and finishing.

             The quality standards for silk fabrics and silk products (such as bedding, pillowcases, scarves, hair accessories, and clothing) depend on the presence of defects in the fabric. Therefore, the most important factor is the quality control of the factory’s output.

              For example, in silk satin fabric,  used for clothing and home textiles, only 5A and 6A silk threads can be used. Lower-grade threads cannot produce this type of silk. The crucial aspect is not whether it's 5A or 6A, but whether the delivered fabric is defect-free and of superior quality.

              Each stage has different focus points. Weaving factories focus on the grade of silk threads because different grades have different prices. Sewing factories are concerned with the defect rate in the fabric. A roll of fabric, about 45 meters long, may have several defect points; the more defects, the higher the fabric waste. Fewer defects mean more usable finished products can be made. No fabric is perfect, and the number of defects in a roll determines its price.

              For customers buying finished products, the focus should be on whether the product has defects, not whether it's 6A silk. 6A does not guarantee that the finished product is perfect or superior.

             Why do people use 6A to denote high-quality silk products?

             Because most customers are unfamiliar with the American Four-Point System standard and find it hard to understand China's quality grading of silk fabrics into superior, first-class, and second-class. However, the 6A standard for raw silk is easily understood: the best threads are expected to make the best fabric. Over time, this led to the habit of using 6A to claim the highest quality.

             As wholesalers and distributors of silk products, it's essential to focus on the defect rate of the products. Quality control in the finished product inspection is the most important aspect.

    Detailed Standards for Raw Silk

                 The grade of raw silk is determined according to the national standard GB1797-86. Based on a combination of physical indicators and appearance quality, raw silk is classified into 6A, 5A, 4A, 3A, 2A, A, B, C, D, E, F, and substandard grades.

                 6A is the highest quality grade for raw silk. Only silk that excels in glossiness, fiber length, fiber elasticity, moisture absorption, and breathability can be classified as 6A.

                 For silk products, the quality standards for Chinese mulberry silk fabrics are evaluated based on the lowest grade item of intrinsic quality and appearance quality. These fabrics are categorized into superior, first-class, and second-class products. Anything below second-class is considered substandard.

                This grading method is derived from the American Four-Point System for fabric inspection. In the Four-Point System, defects in the fabric are counted and scored to rate the fabric per 100 square yards. This system classifies silk fabrics into grades 1, 2, 3, 4, and 5, with higher numbers indicating lower quality. This method is commonly used in Europe, the United States, and Japan.