Discuss the darning of fabric weaves

Expert of the Expert Committee on Laundry and Dyeing Industry of China General Chamber of Commerce   Jiang Xiling

       Profile of Expert Jiang Xiling: She has been working at Beijing Prand Laundry and Dyeing Company since 1977. She holds a college diploma and a professional qualification as a darning technician. She has high technical skills and theoretical knowledge in darning, and has served multiple times as a judge for municipal and national competitions. She is currently an expert of the Expert Committee on Laundry and Dyeing Industry of China General Chamber of Commerce and an expert of the Beijing Laundry and Dyeing Industry Expert Committee. She is passionate about popularizing darning technology in the laundry and dyeing industry. In 2009, she was recognized by the Beijing Municipal Government as a "Master of Chinese Traditional Craftsmanship Skills" in the laundry and dyeing industry.

       Darning is a unique Chinese handicraft. As early as the Qing Dynasty, it became world-famous for winning a gold medal at the Panama International Exposition.

       In the 52nd chapter of the Chinese classical novel "Dream of the Red Chamber," titled "Yong Qingwen Mends the Sparrow Gold Coat While Sick," the author Cao Xueqin provides a detailed description of the darning process: "Qingwen matched the same peacock gold thread, took apart the lining of the garment, fixed it on the back with a bamboo bow, then loosened the edges of the hole with a golden knife, and used a needle to tie two threads, separating warp and weft, similar to the method of inserting threads. First, the base was outlined, then the original pattern of the garment was followed to weave back and forth." This shows that the darning technique has been passed down to this day, leaving historical traces everywhere.

       From the five-meter-wide patchwork technique on the long table in the Great Hall of the People to the darning services for party and state leaders, people from all walks of life, and foreign guests, technicians use only their hands and a slender silver needle to weave yarns one by one according to the fabric's weave pattern, restoring holes to their original state. The magical darning technique has won praise from both domestic and foreign guests.

       Having engaged in darning work for more than thirty years, I can never forget the scenes of my masters teaching me darning skills hand in hand. Whenever I think of this, I sincerely thank my masters for their training. As a master of Chinese traditional craftsmanship skills in darning, I deeply feel the weight on my shoulders and also bear a responsibility, which obliges me to better inherit and develop this darning technique.

       To learn darning, one must first understand the nature, types, and concepts of fabrics. What is fabric structure and its classification, the density of woven fabrics, the thickness, twist, twist direction, color, and appearance of yarns and their impact on fabrics, causes of fabric damage, shapes and application of darning methods, and the operation of darning stitches, etc.

       All items made from textile fibers are collectively called fabrics. Fabrics are divided into woven fabrics and knitted fabrics. The woven fabrics we often encounter in daily life are made by interlacing warp and weft yarns perpendicularly according to certain float patterns. There are many varieties of woven fabrics, each with different properties, characteristics, and uses. Different fiber raw materials determine the nature of the fabric itself. Fabrics suitable for clothing are mainly cotton, linen, silk, and wool. Knitted fabrics are formed by one or more yarns continuously forming loops on a knitting machine, which interlock, connect, compound, and repeat cyclically. They are divided into warp knitting and weft knitting. Common examples include wool sweaters, cashmere sweaters, underwear, briefs, sportswear, T-shirts, and other knitted fabrics.

       There are many variations in woven fabric structures. Understanding the structure and variation rules of various fabric structures greatly helps us identify and master fabric characteristics and darning operations.

       The classification of fabric structures mainly includes: basic structures, variation structures, combined structures, and complex structures. Here, we first discuss the first two types.

1. Basic Structures
       Basic fabric structures include three types: plain weave, twill weave, and satin weave. Basic structures are the simplest fabric structures and also the foundation of other structures. Variation, combined, and complex structures are all formed by changes, developments, and combinations of basic structures.

1. Basic Structures:
       Plain weave is formed by warp and weft yarns interlacing in an "over one, under one" pattern. It is the simplest and most widely used weave. Plain weave fabrics have a flat surface, tight structure, and the front and back look the same. By using different twist directions, twist degrees, yarn thicknesses, and reasonable configurations of colored yarns in warp and weft, plain weave fabrics can achieve various textures and appearances. Common types include horizontal and vertical ribs, subtle stripes, subtle checks, and striped or checked fabrics made with colored yarns, greatly enriching the simplicity of plain weave. When darning, yarn changes in the fabric should be followed promptly to match the original fabric.

2. Twill Weave:
       Twill weave is named for the continuous diagonal lines on the fabric surface. Common twill weaves include 1/2, 2/2, 3/1, 1/3, 3/3, 2/1, etc. Twills can be single-faced or double-faced, left or right twill. For example, single-faced Houndstooth, 1/2 (left twill), and 2/1 (right twill) fabrics have clear diagonal lines on the front, but the diagonal directions differ, and the back looks flat like plain weave. Double-faced Houndstooth 2/2 (right twill) fabrics have diagonal lines on both sides. Although 2/2 twill gabardine has the same structure as double-faced Houndstooth, their darning methods differ. Gabardine has lower warp and weft density and can be darned following the original pattern; double-faced Houndstooth has higher density, making original pattern darning time-consuming and difficult, so a "simplified" method is used. Twill fabrics have longer floats at weave points, giving better hand feel, luster, and elasticity than plain weave, but their abrasion resistance is lower, especially when the weft yarn is Z-twist (S-twist) and very fine, making areas like pockets, hips, and back seams prone to wear and damage.

3. Satin Weave:
From the appearance of the fabric surface, it is significantly different from plain weave and twill fabrics; it is the most complex among the basic weaves. Satin fabric surfaces form some individual, discontinuous, but evenly distributed warp or weft weave points. The floats of the twill on the satin fabric surface are longer, almost covering the warp and weft weave points, appearing broken but not connected; it does not have the obvious continuous and clear twill lines like twill fabrics. Satin fabric surfaces are smooth and glossy, but their abrasion resistance and strength are inferior to plain weave and twill fabrics, and they are easily damaged by abrasion of the warp and weft floats during wear. Common fabrics include dress wool, satin-backed wadmal, silk, and soft satin fabrics.

2. Variation Weaves
Variation weave fabrics are based on the three basic weaves: plain weave, twill weave, and satin weave. By increasing or decreasing the number of warp and weft weave points, float lengths, and the number of floats, and by combining several different weaves together, various new fabric weaves are formed, hence called variation weaves. From the appearance of variation weaves, they still retain some characteristics of the basic weaves, so they are divided into: plain weave variations, twill weave variations, and satin weave variations.

1. Plain Weave Variations:
These are formed by extending the number of weave points in the warp direction, weft direction, or both, based on the "one up, one down" structure. Plain weave variations include warp-heavy plain, weft-heavy plain, square heavy plain, variation heavy plain, and variation square heavy plain weaves. Common fabrics include double filament plain weave fabrics and simple small patterned fabrics.

2. Twill Weave Variations:
These are based on various twill weaves, extending or reducing weave points, increasing twill lines, and changing the direction of twill to obtain various twill weave variations. Common weaves include reinforced twill, steep twill, herringbone (chevron) twill, gentle twill, interspersed twill, broken twill, compound twill, angled twill, diamond twill, shadow twill, etc. In summary, there are many types of twill variation weave fabrics, commonly including herringbone tweed, moleskin, covert tweed, clotted tweed, yin-yang tweed, compound chevron tweed, and others.

3. Satin Weave Variations:
These are based on satin weaves, formed by increasing weave points and changing the number of floats. The main satin weave variations include reinforced satin, shadow satin, and variable satin. In these satin weave variations, the number of warp and weft yarns in a complete weave does not increase, but due to the increased weave points, the length of the floats is shortened, making the fabric appearance clearer and more beautiful, and the fabric's firmness is enhanced.
      
The weaves introduced above have derived new fabric weaves through variations. Changes in the density of warp and weft yarns, yarn thickness, shape, twist direction, and colored yarns in each fabric also add practical, popular, and fashionable elements to the fabric. When repairing fabrics, various factors of the fabric should be considered, combined with the degree and shape of damage, to select the appropriate repair method. This ensures that the weave, pattern, design, and colored yarns of the repaired area match the original fabric.