Modern Weaving of Silk Fabrics

Chinese silk fabrics have reached a high level in ancient times from innovations in design, color matching, craftsmanship, and production technology, especially with the content of various disciplines such as Chinese culture, history, technology, art, astronomy, and geography at that time. Good integration, and even now we see that the study of silk is as connotative and proud as the study of history. Silk products because of its different processing methods, different warp and weft raw materials, fabric organization and color matching different, so the variety of up to thousands

After processing, mulberry silk is divided into warp and weft, and intertwined with each other according to certain organizational rules to form silk fabric, as shown in Figure 1, which is the weaving process. The production process of various types of silk fabrics is not the same, which can be roughly divided into two categories: raw weaving and cooked weaving, as shown in Figure 2.

Raw weaving, that is, the warp and weft silk is made into a fabric without practicing and dyeing, which is called a blank silk, and then the blank silk is practiced and dyed into a finished product. This kind of production method has low cost and short process, which is the main method used in silk weaving production at present.

Ripe weaving means that the warp and weft yarns are dyed before weaving, and the woven blank silk does not need to be dyed into the finished product. This method is mostly used in the production of high-grade and complex silk fabrics, such as brocade, jade satin, velvet, cloud brocade, song brocade and taffeta.

Before weaving, there is still a lot of work to be done, which we call the preparation process. Such as the softening of sericin impregnation, can improve the performance of the product and twisted silk, shaping, twisted, dyeing and the whole, fine collaterals, etc., different products of different processing processes. Take taffeta as an example: its warp direction and weft direction each need more than 20 processes, which does not include the inspection and repair of silk after weaving. See Figure 3 for taffeta. At the same time, due to the strong moisture absorption of silk, but also to do a good job of moisture-proof work, the current silk production is carried out in the workshop to control the temperature and humidity conditions.

The basic process of silk fabric production is:

At present, the modern looms used in the production of silk mainly include: rapier looms and projectile looms for the production of plain and multi-colored weft jacquard fabrics, air-jet looms for a variety of fibers, and water-jet looms for the production of synthetic filament fabrics.

Raw material

Mulberry silk, also known as white silk, silk, raw silk, is an animal protein fiber. It is composed of silk fibroin and sericin, which is a natural green environmental protection fiber. Common specifications are

21.1/23.3dtex(19/21D),22.2/24.2dtex(20/22D),30.0/32.2dtex(27/29D),44.4/48.9dtex(40/44D), etc. The special filaments are 13/15D and are produced in Zhejiang, Jiangsu, Sichuan, Shandong, Guangdong and other places. See Figure 4 for silk raw materials.

Detection

According to the national standards, the fineness, strength, elongation, holding, moisture regain, cleaning and cleanliness of the white factory silk are tested, as shown in Figure 5. The quality standard grade is divided into: B, A, 2A, 3A, 4A, 5A, 6A grade.

Each strand shall be inspected one by one, and defects such as color, flowers, sundries and roughness shall be picked out.

Dip/Color

Its purpose is to soften the sericin of silk, to facilitate and twist. The sericin of silk is softened with impregnation solution (about 3% of sericin can be removed after impregnation). The weft is usually impregnated for 18h and the warp for 40min. The main methods of impregnation are mechanical impregnation, vacuum impregnation and manual impregnation, as shown in Figure 6.

The color is a mark made for the subsequent process to identify the stripes, combined number, twist, twist direction, origin and batch number of various filaments. Coloring is carried out simultaneously during immersion, and the dyes used will all fade during refining without leaving traces.

Drying/air-drying

All kinds of silk that are impregnated or colored only must be dried in time for use. The drying method can be used after the dehydrator is taken off, and the glue wire drying machine (8h) or drying room (24h) or natural drying is used, as shown in fig. 7.

wire

Winding the stranded wire on the side bobbin. Any twisted wire, whether used for warp or weft, parallel wire, twisted wire or not, must be wound into a bobbin by a winding machine for the next process, as shown in Figure 8.

and silk

According to the requirements of fabric weft processing, combine 2-6 or more monofilaments of different specifications with a drawing machine and wind them on a parallel tube, as shown in Figure 8.

twisted silk

Where there is a need to have a twist of more than 200 within 1m, monofilament or parallel filaments must be completed by twisting with a twisting machine. Now there are also more efficient two-for-one twisters. The twist direction is divided into S twist and Z twist. When the twist reaches 2000 twists/m or more, it is called strong twist. The appearance of the finished fabric can be changed by twisting and fabric texture design and finishing. Such as Crepe de Chine, Joe, etc., see Figure 9.

Stop twisting/setting

After twisting, especially strong twisted yarn, it is easy to shrink and the twist is not stable, so it must be stopped. But not because of the twist and damage the silk line strength, elongation, elasticity and other indicators. The stop twisting is done by the steamer. Low twist can also be done by intertidal and natural setting. Of course, after the twist is stopped, due to the influence of steam, the sericin of the twist is bonded to each other, which hinders the subsequent process. Therefore, the twisted yarn must be unwound from the twisted yarn bobbin after the twist is stopped. At this point, it can be completed by using the drum rewinding machine and the precision winder, as shown in Figure 9.

into a twist

Shake the bobbin yarn into strands according to the length specified in the process to facilitate the processing of the following process. After the twisted yarn is dyed and inspected, the twisted yarn must be wound on the bobbin applicable to the subsequent process through a winding machine, as shown in Figure 10.

whole warp

The whole is a very important part of the preparation process. According to the warp number, length and amplitude requirements required by the fabric specifications, the processed silk on the winding tube is wound on the warp shaft by using a warping machine to form the warp required for the fabric. Tension devices will be provided on each bobbin to ensure the stable tension of thousands of warp yarns. This is a process that all silk fabrics must go through, as shown in Figure 10.

Wear heald, reed and machine

After the whole meridian, according to the organization point of the fabric organization, in order to wear a heald, wear a reed. After putting on the heald and reed, the warp beam, together with the reed and the heald, is a necessary procedure for a new variety of looms. If the loom is the continuation of the original variety, the continuation of the warp axis can be completed by means of joints without wearing healds and reeds.

weaving

The warp and weft threads completed by the preparatory work are interlaced into silk by means of a silk loom. Plain fabrics are generally woven by dobby machines, and jacquard fabrics must be woven by jacquard machines.

Inspection of green/colored green silk

The silk and satin produced by the loom is inspected meter by meter, so as to effectively monitor some defects in the previous process, prevent the same defects in the future, and also remedy the defects. At the same time, the dyeing and training factory can have some understanding of the silk and satin in the weaving factory, so as to improve the dyeing and testing rate of the silk and satin.

In fact, the development of modern looms is very fast. In addition to the weft insertion technology, there are air-jet and water-jet looms. The intelligence of rapier and projectile looms has been further improved and has gradually replaced the shuttle looms in the past, as shown in Figure 11. At the same time, the matching electronic jacquard machine, electronic dobby machine, automatic control system, intelligent weaving technology, pattern rapid design, related CAD software and fabric simulation are developing rapidly, which can be matched with the loom. The weaving data, process parameters and production management of each loom in the workshop can be controlled and set through the two-way transmission of the central controller. The intelligent development of modern looms and their supporting equipment is very fast, and the development and production process of silk fabrics are also constantly inherited and innovated.

Documentation

Source: Modern Silk Science and Technology 2018 (Volume 33) No. 1, "Silk Culture and Products" Writing Group